Ectopic Pregnancy and Assisted Reproductive Technologies: A Systematic Review

Ectopic pregnancy represents a rare pregnancy complication. In the last 20 years, with the use of IVF, heterotopic pregnancies have become more frequent, while this percentage differs between IVF programs. Many factors contribute to this, like the active management of hydrosalpinx or treatment of Chlamydia infection before starting a cycle. Although, in vitro fertilization is an expensive treatment, ectopic complication adds to this cost. Not a lot of studies exist for ectopic pregnancy after IVF. Most of them are case reports. Not a standard way exists, for dealing with heterotopic pregnancies, even in the era of modern laparoscopy. Not a lot of research has been performed on molecules that involved. Studies have tried to associate certain techniques during IVF, with this entity, but with controversial results. There is no standard form for diagnosing, dealing and presenting heterotopic pregnancies. Most of them are diagnosed when ruptured. Because it is rare event, costeffectiveness studies could not be performed and this complication is added to the overall IVF. Knowledge, on this field, is taken from the management of ectopic pregnancies in the general population, even if these present at a lower percentage. The purpose of the study is to systematically evaluate studies on molecular aspects of ectopic pregnancy, the ART techniques that are associated with ectopic pregnancy, the diagnosis of this entity and finally present case reports of heterotopic pregnancies and their management. At the end, cost-effectiveness models from the general population will be presented in parallel with systematic examination of these studies. Finally, new research targets will be pointed.


Introduction
Ectopic pregnancy represents a rare pregnancy complication. In the last 20 years, with the use of IVF, heterotopic pregnancies have become more frequent, while this percentage differs between IVF programs. Many factors contribute to this, like the active management of hydrosalpinx or treatment of Chlamydia infection before starting a cycle. Although, in vitro fertilization is an expensive treatment, ectopic complication adds to this cost. Not a lot of studies exist for ectopic pregnancy after IVF. Most of them are case reports. Not a standard way exists, for dealing with heterotopic pregnancies, even in the era of modern laparoscopy. Not a lot of research has been performed on molecules that involved. Studies have tried to associate certain techniques during IVF, with this entity, but with controversial results. There is no standard form for diagnosing, dealing and presenting heterotopic pregnancies. Most of them are diagnosed when ruptured. Because it is rare event, costeffectiveness studies could not be performed and this complication is added to the overall IVF. Knowledge, on this field, is taken from the management of ectopic pregnancies in the general population, even if these present at a lower percentage. The purpose of the study is to systematically evaluate studies on molecular aspects of ectopic pregnancy, the ART techniques that are associated with ectopic pregnancy, the diagnosis of this entity and finally present case reports of heterotopic pregnancies and their management. At the end, cost-effectiveness models from the general population will be presented in parallel with systematic examination of these studies. Finally, new research targets will be pointed.

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Regulators T cells (Treg) express LH/CG receptor on their surface during pregnancy and are present at the fetal-maternal interface, attracted by high levels of human chorionic gonadotrophin. In ectopic pregnancies, regulatory T cells are not attracted to the same degree by the lower levels of hCG (Schumacher et al., 2009). Another possible biomarker for ectopic pregnancy after IVF is E-cadherin, because it is highly expressed in cytotrophoblast cells of chorionic villi from these pregnancies, when compared with spontaneous ectopic pregnancy (Revel et al., 2008). From micro-array studies, Savaris et al, by using the model of ectopic pregnancy, found that the transcriptome of the decidua is influenced by trophoblast products, in endocrine fashion (Savaris et al., 2008). In close proximity of the tubal implantation site, MUC-1 and TAG-72 are present in the epithelial cells and might contribute to the deeper trophoblast invasion in the tubal wall (von Rango et al., 2003) while a significant reduction in NK-cell numbers at the tubal implantation site, could be seen, induced by local antigen-presenting cells in the presence of mucins (Laskarin et al., 2010). Viable tubal pregnancies implant at the mesosalpingeal side of the tubal wall show a massively increased invasion of extravillous trophoblast cells (EVT) into the tubal wall, and the proliferation of trophoblast cells extends deeply into the invasive zone in the invasive pathway (Kemp et al., 1999). Tubal pregnancies that will undergo tubal abortion implant at the antimesometrial side which show shallow invasion and poor trophoblast proliferation (Kemp et al., 1999). In extrauterine pregnancy, expression of integrin subunit 3 is nearly exclusively restricted to the basal plasmalemma of the first layer of trophoblast cells while only the first proximal layer of EVT (in direct contact to the basement membrane) expresses integrin 6. The switch to the integrin subunits v and 5 takes place already in the second layer of trophoblast cells, as soon as the latter detach from the basement membrane (Kemp et al., 2002). In tubal pregnancies, MMP-9 and TIMP-1, -2 and -3 are produced by all types of extravillous cytotrophoblast (EVCT) cells, while MMP-2 and -14 mainly exist in distal column cytotrophoblast (CCT) cells and invasive EVCT cells (Bai et al., 2005). In parallel, MMP-14 and TIMP-1 and -2 are increased along the invasive pathway toward maternal interstitium. MMP-2, -9 and -14 and TIMP-1, -2 and -3 were all detected in the villous CT (VCT) cells (Bai et al., 2005). Another promising technique for early detection of an ectopic pregnancy is that trophoblast cells can be reliably obtained and identified among cervical cells in the first trimester and labeled with antibody to HLA-G. The number of trophoblast cells per total cervical cells (trophoblast frequency) is significant lower in ectopic pregnancy when compared to intrauterine pregnancy but not to blighted ovum (Imudia et al., 2009). Using ROC curves the positive predictive value for abnormal pregnancy was 97% and the negative predictive value was 87%. From intrauterine tissue and sera, Horne et al, examined PIGF, localized to the cytotrophoblast cells (Horne et al, 2010). Expression of PIGF mRNA was significantly reduced in trophoblast cells, isolated from women with ectopic pregnancy compared with intrauterine pregnancies. Serum PIGF was undetectable in women with tubal ectopic pregnancies and reduced, or undetectable, in miscarriage compared with viable intrauterine pregnancies. From the other side, it seems that SLT/ROBO pathway and protein expression in endometrium and fallopian tube, is not implicated in ectopic pregnancy because known factors that contribute to EP (e.g. smoking/cotinine or chlamydial infection) do not alter protein expression (Duncan et al., 2010). Also serum VCAM-1 was found comparable between the three pregnancy types, normal, ectopic and failed thus making this marker not useful for the diagnosis of ectopic pregnancy (Daniel et al., 2000). Also a role for ectopic pregnancy formation might exist from ovulation induction regimens. Clomiphene citrate, which used for anovulatory infertility, may indirectly contribute to ectopic pregnancy creation. Chronic treatment with clomiphene activates estrogen receptors, particularly in cilia, and inducing tubal apoptosis of isthmus epithelial cells while slowing oocyte cumulus complex passage from the fallopian tube (Shao et al., 2009). This may contribute to ectopic pregnancy formation.

Ectopic pregnancy and IVF
A total of 56 abstracts were retrieved and further screened. Out of 40 included studies, 10 (25%) were performed in USA, 3 (7.5%) in England, India and in Netherlands, 2 (5%) in France, Greece, Israel, Italy and Nepal, while 1 (2.5%) in Australia, Canada, Germany, Japan, Jordan, Korea, Norway, Singapore, Taiwan, Thailand and between USA/Sweden. 17 (42.5%) of them considered themselves retrospective, 11 (27.5%) as case report, and from 1 (2.56%) as cohort study, prospective randomized double blinded cross over study, prospective cohort study, population based cost-effectiveness study, epidemiological study, economical analysis, cost effectiveness analysis, cost benefit analysis, cost analysis, while 3 (7.5%) do not mentioned the type of study. The type of study per country initiated can be seen in  All studies selected used human tissue. Fourteen studies mentioned embryo (35%) as tissue examined plus 4 (10%) mentioned especially the blastocyst, 4(10%) used fallopian tube and from 1 (2.5%) used embryos with thickened zona pellucida, fallopian tube ectopic pregnancy and sperm with abnormal characteristics, hydrosalpinx, ovarian tissue and trophoblastic tissue, while one tested newborns for congenital abnormalities after failed emergency contraception while 12 (30%) did not specified the tissue examined. The type of study per tissue used can be seen in  Samples size examined ranged from 1 (case reports) to 44. Disease distribution examined presented as: ectopic pregnancy (17/42.5%), and from 1 (2.5%) bilateral tubal ligation, chlamydial infection-tubal infertility-ectopic pregnancy ,ectopic pregnancy on patients after IVF with abnormal sperm characteristics, ectopic pregnancy after oocyte donation in menopausal patients, ectopic pregnancy after donation surviving even with the absence of exogenous steroids, ectopic pregnancy after embryos with thickened zona pellucida, ectopic pregnancy after empty follicle syndrome, ectopic pregnancy after exposure to levonorgestrel, heterotopic abdominal pregnancy, heterotopic abdominal pregnancy, ectopic pregnancy after hydrosalpinx, menopause and oocyte donation, ovarian heterotopic pregnancy, ectopic pregnancy after pelvic inflammatory disease, pelvic inflammatory disease-ectopic pregnancy and neonatal complications, primary infertility, tubal factor infertility and bilateral ovarian pregnancy, tubal sterilization while 3 (7.5%) did not mentioned disease. Funding source of each study per Journal published is seen on

Outcomes 5.2.1 Factors contributing to ectopic pregnancy after IVF
Pyrgiotis et al, retrospectively analyzed a large series of fresh (n=2812) and frozen embryo transfers (n=405) showing a 2.4% and 7.6% EP rate, respectively (Pyrgiotis et al., 1994). Tubal factor presented as 85.7% of all causes of ectopic pregnancies. In a previous study, an EP rate of 3.3% was found (26 patients) and the major contributing factor was a prior ectopic (Karande et al., 1991). Heterotopic pregnancy rates remained low in both studies while the majority of them were tubal. Also cervical pregnancies were low.
Clayton et al, in the largest series of 94.118 pregnancies found an EP rate of 2.2% in fresh non-donor cycles while ZIFT procedures EP rate was 3.6% (Clayton et al., 2006). Tubal factor with or without hydrosalpinx was the main factor of ectopic pregnancy while endometriosis, uterine factor and diminished ovarian reserve was some of the less but important factors. Although all other factors may be well understood, the last factor could be explained from the fact that when higher implantation embryo potential was present, EP rate was minimal. When two or less embryos transferred, then the EP rate was less than when three or more embryos transferred. To the extent of the previous study, abnormal embryogenesis was a major factor for ectopic pregnancy. From this study it was found that DNA aneuploidy was associated with tubal implantation in 33% (Karikoski et al., 1993). Similar rates (24%) of abnormal amount of DNA content in tubal pregnancies was found also by Toikkanen et al., 1993. In a recent study Chang et al, found that tubal factor infertility and endometriosis was the main factor (Chang et al., 2010). Tubal surgery and previous ectopic pregnancies was another important factor while risk for EP was seriously decreased with a previous live birth. Donor oocytes do not attribute to more ectopic pregnancies and this apply to higher embryo implantation potential, as mentioned above. Contradictory to previous results, Bhattacharya et al, found that ectopic pregnancies in IVF are associated with significantly lower percentage of motile sperm (Bhattacharya et al., 2010). A more detailed approach follows:

Heterotopic pregnancy
It is considered a rare entity of ectopic pregnancy (1/30000) and could be seen especially after IVF(<0. 01) (Dimitry et al, 1990;Molloy et al., 1990). It has been presented in literature in various forms: 1) Triplet heterotopic pregnancy a) in a previous caesarian scar and intrauterine pregnancy b) a tubal singleton and two intrauterine pregnancies and an ovarian abscess c) bilateral tubal and intrauterine pregnancy 2) Cornual pregnancy a) recurrent cornual pregnancy b) cornual pregnancy and twin intrauterine pregnancy 3) heterotopic pregnancy with intrauterine dizygotic twins after blastocyst transfer 4) heterotopic cervical pregnancy a) intrauterine and twin cervical pregnancy b) cervico-istmic pregnancy 5) Heterotopic pregnancy in parallel with ovarian hyperstimulation syndrome 6) heterotopic pregnancy ruptured after spontaneous abortion. Eventually the presence of an intrauterine gestation sac in a patient without symptoms should not exclude the diagnosis of a concomitant extrauterine pregnancy until the pelvis is carefully visualized (Rizk et al., 1991).

Differences in the prevalence in different countries of the world
EP complicates about 2% of all pregnancies. Although no studies exists that specifically describe the prevalence in different countries, especially after IVF treatment, certain studies present this, as a secondary outcome. In Nigeria (Okohue et al., 2010), prevalence for EP was 7.8% after IVF, while in general population in the same country, EP rate was 1.74% (Musa et al., 2009). The same percentage in Jordan was 0.005% (Obeidat et al., 2010). In Cameroon, this percentage is 0.72% (Leke et al., 2004). In a large follow up study, in Sweden, ectopic pregnancy rates where compared between women from different countries of birth, but small differences were found (Eggert et al., 2008). In New York, ectopic pregnancy rates in black women are 4.78% (Fang et al., 2000).

Contraception as a risk factor
Ghosh et al, described a right ampullary ruptured ectopic pregnancy after the failure of levonorgestrel as emergency contraception (Ghosh et al., 2009), while Fabunmi and Perks, reported a case of Caesarean section scar pregnancy after the same LNG failure (Fabunmi & Perks, 2002). From the other side, opposite to the numerous case reports, De Santis et al, in a retrospective observational cohort study found no association of LNG failure with ectopic pregnancy (De Santis et al., 2005).

Ectopic pregnancy rates in fresh vs. frozen cycles
Controversy exists in this issue. Jun et al, found no difference in ectopic pregnancy rates between fresh and frozen cycles while Yanaihara et al, found a significant difference in ectopic pregnancies when two frozen blastocysts were transferred, than one (Jun et al., 2007;Yanaihara et al., 2008). From the other side, Ishihara et al, in a large registry retrospective study, found that frozen-thawed single blastocyst transfer significantly reduce EP rates (Ishihara et al., 2010). Even when data were stratified for age, EP rates varied, but remained low.

Day 3 versus day 5
Milki et al, found no difference in ectopic pregnancy rates when blastocyst transfer compared with day 3 embryo transfer (Milki et al., 2003). In this study important confounding factors like tubal disease between the two groups, cryopreserved transfers but not number of embryos transferred were checked between the two groups and no significant difference was found.

Blastocyst (single vs. double blastocyst transfer)
Knopman et al, reported a heterotopic abdominal pregnancy after the transfer of two blastocysts (Knopman et al., 2006). Intrauterine pregnancy miscarried first while abdominal pregnancy ruptured two weeks later and ectopic removed by laparoscopy. Ectopic pregnancies are significant lower when single frozen-thawed blastocysts transferred compared with two blastocysts (Yanaihara et al., 2008).

Oocyte donation and ectopic pregnancy rates
Cohen et al, found that hydrosalpinx patients that undergo oocyte donation have higher ectopic pregnancy rates than patients in the same program with no hydrosalpinx (Cohen et al., 1999). Possible explanation for that is the chronic alteration of endometrium rather the direct embryotoxic effect of hydrosalpinx fluid. In case, after oocyte donation, an ectopic takes place, minimal monitoring may allow rupture of ectopic with significant complication (Ledger et al., 1992). Mantzavinos et al, reported three case of ovarian pregnancy after oocyte donation (Mantzavinos et al., 1994). Cases were resolved with laparoscopy and removal of ovarian pregnancy tissue. Pantos et al, in a large series of donation patients found only one ectopic pregnancy (Pantos et al., 1993). Rosman et al, in a large retrospective study (4186 non-donor IVF cycles vs. 884 donor ET cycles found that there is no difference in ectopic pregnancy rates between donor and IVF cycles (Rosman et al., 2009). From the other side, donor patients showed significant lower incidence of tubal disease than standard IVF patients.

The ICSI role
In a large retrospective study, Clayton et al, found that use of ICSI was not associated with EP while male factor infertility was associated more with EP with all other races than whitenon-Hispanic (Clayton et al., 2006).

Ultrasound guided embryo transfer
In a meta-analysis of clinical trials (on 5,968 ET cycles), comparing ultrasound guided ET vs. clinical touch ET (Abou-Setta et al., 2007), it was found that ectopic pregnancy rates were no different between the two groups. In a another meta-analysis on 17 studies, (Brown et al., 2010), it was found the same results, although it was stated that EP are relatively rare and study sample sizes limit the ability to detect such differences. Even when a single clinician performs all embryo transfers, (Kosmas et al., 2007), no difference in ectopic pregnancy rates was found.

Assisted hatching
Hagemann et al, found no difference in ectopic pregnancy rates in patients that their embryos had assisted hatching or not (Hagemann et al., 2008). From the other side Milki et al, in a large series of retrospectively examined patients saw that a significant higher ectopic pregnancy rate was found in cases where assisted hatching (AH) was performed when compared with cases that hatching was not preformed (Milki et al., 2004). Possible explanation for that is: 1) assisted hatching may accelerate embryo implantation, 2) a mechanism exists, that prevents embryos that reached fallopian tube to divert back to uterus and 3) the much higher embryo transfer volume that used in certain IVF programs.

Air bubble position after embryo transfer
No difference in ectopic pregnancy rates was observed with different distances of embryo deposition from the uterine fundus (10-15 mm or < 10 mm) (Pacchiarotti et al., 2007).

Reanastomosis
Patients with tubal infertility may undergo microsurgical reconstructive surgery of the fallopian tubes for adhesiolysis, anastomosis, fimbrioplasty, salpingostomy, and refertilization after former sterilization. These patients, if choose the microsurgical approach, show higher ectopic pregnancy rates after a single IVF trial (Schippert et al., 2009). From the other side, in a small series of patients, higher incidence of ectopic pregnancies was observed when previous tubal sterilization was reversed by laparoscopy than open microsurgical reversal (Tan et al, 2010). Even if suture less laparoscopic tubal re-anastomosis was performed (using a serosamuscular fixation/biological glue technique) an ectopic pregnancy rate of 3.9% was observed (Schepens et al., 2011). In a small series of robotic tubal reanastomosis (Dharia Patel et al., 2007) more ectopic pregnancies were observed when compared with open reanastomosis.

Other complications of ectopic pregnancies
Rh immunization could be observed in ruptured ectopic pregnancy.

Section 3 6.1 Diagnosis of an ectopic in IVF
Pregnancies of unknown location include viable pregnancies, ectopic pregnancies and miscarriages (Condous et al., 2005). Only a small portion of them are high risk pregnancies (Condous et al., 2005) and there is difficulty in diagnosis and management. Serial measurements of hCG and progesterone should be performed on a wait and see approach, in parallel with TVS. Serum hCG increase over 48 h of more than 66% -that is, an hCG ratio of >1.66 -correlates well with a developing intrauterine pregnancy. The use of discriminatory zone technique (Condous et al., 2005), is currently evaluated for prediction of probability of ectopic pregnancy. By this technique, if an intra-uterine sac cannot be seen on ultrasound scan above the threshold value, then steps must be taken to determine whether the pregnancy is abnormal or ectopic. After that a D&C can be safely performed only when a non-viable pregnancy has been documented by either a serum progesterone level of 15.9 nM or the absence of a rise in serum hCG after 2 days; that is, an hCG ratio of <1.50 (Pisarska et al., 1998).

Transvaginal ultrasound and hCG levels for prediction
With the use of TVS, before 35 days a pregnancy could be considered as a pregnancy of unknown location, from 35 to 41 days a pregnancy of uncertain viability and from 42 days a viable intrauterine pregnancy (Bottomley et al., 2009. Time for diagnosis of ectopic pregnancy was 48 days. In case, previous ectopic pregnancies took place, then diagnosis could be made before this time. Viability scans should be deferred until 49 days of gestation with a minimal benefit delaying after that. The addition of abdominal pain and vaginal bleeding ads to ectopic pregnancy risk. Statistical models have been developed, based on the hCG ratio to predict the outcome of pregnancies of unknown location and especially ectopic pregnancies (Kirk et al., 2006), but this is not easily implemented in clinical practice.

Newer biomarkers for ectopic pregnancy
Daniel et al, tested for serum sVCAM-1, ectopic and normal pregnancies, but did not found any difference (Daniel et al., 2000). C. trachomatis antigen and nucleic acid could be found at 33% among ectopic pregnancies tissue even if they are negative for cervical Chlamydia (Toth et al., 2000). Activin A subunit, type II receptors, follistatin, and iNOS show increased expression within the fallopian tube of ectopic pregnancy patients tested serologically positive for C. trachomatis (Refaat et al., 2009). Especially for iNOS, elevated activity positively correlates with protection from hydrosalpinx formation and prevention of the systemic spread of C. trachomatis. In a clinical setting, Florio et al, found that Activin A levels were significantly lower in spontaneous abortions and intrauterine pregnancies than ectopic ones,and at the cutoff of 0.37ng/ml a sensitivity and a specificity of 100 and 99.6%, respectively, was achieved, for prediction of EP (Florio et al., 2007). From the other side, on a different approach, Kirk et al, found no more discriminatory capacity of Activin A and inhibin than serum hCG levels for ectopic pregnancy in case of a pregnancy of unknown location

Section 4 7.1 Management of specific ectopic pregnancies
In this section, a total of 26 abstracts were retrieved and further screened. Only studies that performed clinical interventions for ectopic pregnancy after IVF were included in this part. Out of 16 included studies, 5 (31.25%) were performed in Taiwan, 4 in USA (25%), 2 in Italy (12.5%), 1 (6.25%) in France, 1 in Germany (6.25%), 1 (6.25%) in Netherlands, 1 in Turkey (6.25%), and one in Serbia and Montenegro. 15 (93. 75%) of them considered themselves case report while 1 (6. 25%) clinical. The type of study per country initiated can be seen in Fig 9.   Fig. 9. The type of study per country initiated All studies selected used human tissue. Thirteen studies did not mention anatomical tissue used (81.25%). From the other studies 1 (6.25%) used fallopian tissue, 1 used endometrium & fallopian tube, and one used cornual pregnancy. The type of study per tissue used can be seen in Fig 10. Samples size examined ranged from 1 (case report) to 104. Disease distribution examined presented as: heterotopic cesarean scar pregnancy, (5/31.25%) (one study described ectopic twin pregnancy in a Cesarean section scar (1/6.,67%) and a second described a triplet heterotopic cesarean scar pregnancy), heterotopic cervical pregnancy (4/25%), cornual pregnancy (1/6.25%), heterotopic cornual pregnancy, heterotopic triplet pregnancy, Intersitial Heterotopic pregnancy, unilateral ectopic twin pregnancy while one study did not mentioned the type of ectopic pregnancy. Tissue used per disease is seen on Fig12.  Five studies (31.25%) did dot used any pharmacological interventions while the other 11 described it: two studies used potassium chloride, one study used sodium chloride, one used systemic methotrexate, one used vasopressin. The other six studies described the pharmacological interventions from IVF, previously performed.

Rare cases of ectopic pregnancies
Papers that report ectopic pregnancies after IVF and their clinical picture will be presented in this section. Case studies will be presented according to anatomical location and management.

Ovarian ectopic pregnancies
In a large series of patients, Raziel et al., found that ovarian ectopic pregnancy rate comprises 2.7% of all ectopic pregnancies, is highly associated with the use of intrauterine device and treated with laparoscopic wedge resection (Raziel et al., 2004). The use of ultrasound for diagnosis of hemoperitoneum makes culdocentesis not necessary. Case reports presenting ovarian ectopic pregnancies present: 1) ovarian heterotopic pregnancy after IVF (Kamath et al., 2010), 2) bilateral ovarian pregnancy after IVF and previous tubal pregnancy after reanastomosis (Han et al., 2004), 3) left ovarian pregnancy after empty follicle syndrome in IVF treatment (Qublan et al., 2008), 4) ovarian pregnancy from cornual fistulae after bilateral salpingectomy and IVF treatment (Hsu et al., 2004).

Management of a late ectopic pregnancy
A case of a cervical intrauterine pregnancy has been reported by Fruscalzo et al., after IVF (Fruscalzo et al., 2007). At the 13 th gestational week, a viable intrauterine pregnancy and a non viable cervical pregnancy were diagnosed. The cervical pregnancy was anteriorly confined near a thick cervical blood vessel with low resistance flow at Doppler ultrasound. Due to the proximity to the cervical venous vessel, there was increased hemorrhagic risks associated with a cervical pregnancy expulsion After hospitalization and observation, cervical pregnancy was expulsed at 15 th gestational week + 6 days and hemorrhage was managed through cervical curettage and multiple cervical stitches under general anesthesia. Unfortunately, some hours later, intrauterine pregnancy expulsed also, leading to a curettage. Another case of heterotopic pregnancy at 16 wks gestation after IVF was presented by Hassiakos et al., 2002. It was ruptured and presented with intra-abdominal bleeding and hemorrhagic shock.

Maternal-embryo complications from use of Potassium chloride
A study by Gyamfi et al, described a cervical heterotopic pregnancy (one in the intrauterine cavity and the other in the upper portion of the cervix) treated with KCl (3 mL ) injection and aspiration of the gestational sac contents (Gyamfi et al., 2004). A blood supply, separate from that of the remaining pregnancy was seen at 19 wks by color Doppler. Unfortunately remaining trophoblastic tissue did not resolve, leading to obstetric hemorrhage at 31 wks gestation and subsequently to emergency cesarean hysterectomy with a viable infant,while patient waited for an elective Cs at 32 wks. Another possible complication of this technique is that diffuse of KCL in the target amniotic sac, may lead to diffuse to adjacent sac, thus makes harm to the intrauterine embryo.

Rare ectopic pregnancies 7.3.1 Cervical pregnancies
A heterotopic cervical pregnancy treated with TVS-guided aspiration at day 34 after her embryo transfer, developed of uterine varices at the cervical site, bilateral hypogastric artery occlusion was used while a fundal classic cesarean section at 37 weeks gave birth to an infant (Shah et al., 2008). Uterine varices were diagnosed at 28 weeks gestation, as prominent vessels associated with the empty sac located anteriorly and posteriorly occupying a significant portion of the myometrium of the lower uterine segment and cervical stroma. Venous waveforms were observed on Doppler studies. Fundal C section was planned to avoid entry into the gestational tissue and vasculature that occupied the lower uterine segment. After delivery, the patient went for pelvic angiography and possible embolization to diminish the risk of bleeding. Prorocic et al. described the treatment of a heterotopic cervical pregnancy with TVS-guided aspiration and instillation of hypertonic solution of sodium chloride and ligation of descending cervical branches of the uterine arteries (Prorocic et al., 2006). The latter took place before TVS guided aspiration. By vagina retraction, two DEXON sutures were placed bilaterally on the cervix, high below the fornix vaginae thus reducing hemorrhage, significantly. Twin pregnancy in the uterine cavity continue to grow till article publication (at 12 th week of pregnancy). A cervical twin ectopic pregnancy has been described by Aboulfoutouh et al. (Aboulfoutouh et al., 2011). Treatment consistent from transvaginal ultrasound-guided aspiration plus systemic single injection of methotrexate. A 37-year-old woman after IVF developed severe ovarian hyperstimulation syndrome. Transvaginal ultrasound revealed two gestational sacs with one viable fetus located below the internal cervical os at 7 weeks' gestation while Doppler imaging demonstrated a cervical mass containing numerous tortuous and dilated blood vessels and vascular communication beds in the implantation site and established abundant peritrophoblastic arterial flows. 2 days later developed vaginal bleeding and Intracervical Foley catheter tamponade was performed. Persistently active gestatinal tissue and bleeding leads to hysteroscopic endocervical resection (12-degree resectoscope with an outer diameter of 8 mm) in combination with temporary balloon occlusion of bilateral common iliac arteries (CIA). After complete removal of gestational tissue, electrocoagulation was done using the rollerball for homeostasis. After that, a 24-Fr Foley balloon catheter was placed at the cervical canal to achieve homeostasis while methotrexate 50 mg im was injected on the following day, and the 24-Fr Foley balloon catheter was removed 3 days after surgery (Yang et al., 2010). Same method of treatment was used by Peleg et al. (Peleg et al., 1994). A 45-year-old woman, diagnosed by ultrasound with a triplet gestation 7 weeks following IVF. Transvaginal ultrasound showed a triplet heterotopic pregnancy consisting of two gestational sacs in the cervix and one in the uterine cavity. Termination of pregnancy was decided for future fertility preservation with catheterization and methotrexate treatment. The right femoral artery was catheterized with catheter and the uterine arteries were cannulated. 42 mg of methotrexate were injected into the right and left uterine arteries (total dose of 84 mg (50 mg/m 2 )). Pledgets of Gelfoam were then used to embolize the arteries. Follow-up ultrasound scan (after 48 hours) revealed an absence of cardiac activity in both embryos. A gradual shrinkage of the cervical and intrauterine sacs was seen later (Nitke et al., 2007).
A 37-year-old woman undergone ICSI, due to severe oligoasthenoteratospermia, diagnosed with transvaginal ultrasound two gestational sacs with embryonic heartbeats, one in the cervical region and the second intrauterine. Hysteroscopic removal of the cervical gestational sac was chosen, to preserve the intrauterine pregnancy. The gestational sac was observed on the left side of the endocervical canal 2 cm away from the internal cervical ostium The tip of the resectoscope did not go beyond the internal cervical os during the operation, and the uterine cavity was not touched. By roller ball electrocatery was used for the conception products. Cautery settings were 100 W for cutting, and the coagulation current blend was 1. The entire procedure was performed under continuous ultrasound guidance with an abdominal probe (Jozwiak et al., 2003). A viable intrauterine and cervical pregnancy was diagnosed in a 34-year-old woman in her 4 IVF attempts. With transabdominal scanning, needle was inserted transcervically and maneuvered into the embryo fetal heart that ceased. After that KCl injected. Then 3 cm 3 of saline were injected for better visualization of the cervical fetus, and to confirm absence of heart beat. The intrauterine pregnancy delivered art 36,5 wks (Carreno et al., 2000). A heterotopic cervical pregnancy diagnosed 25 days after ET because the patient reported some mild vaginal bleeding. Transvaginal ultrasound and Doppler vascular blood flow confirmed the suspected heterotopic cervical pregnancy that was treated with transvaginal ultrasound-guided aspiration and KCL injection in the heterotopic pregnancy cavity. Sixteen days after the procedure, and under epidural anesthesia, hemostatic synthetic absorbable sutures were placed high on the cervix at 1, 3, 9, and 10 o'clock, ultimately circumferentially tying the cervix. Cervical-stay sutures dissolved by the 18 th -20 th weeks of gestation while no cervical incompetence was observed. At 38 weeks of gestation, via cesarean section an infant was delivered. For safety precautions, during the procedure, interventional radiologists were on standby to perform uterine artery embolization if necessary (Chen et al., 2001).

Previous myomectomy scar
Although pre-IVF myomectomy is not a necessity to achieve an ongoing pregnancy (Vimercati et al., 2007), other authors prefer to perform it, especially when repeated implantation failures takes place (Margalioth et al., 2006) or uterine cavity involvement exists (Klatsky et al., 2007). In a retrospective study for laparoscopic myomectomy outcomes, Paul et al, mentioned a 5.2% EP rate (Paul et al., 2006). In the same year, Seracchioli et al., reported an EP rate of 2.6% (Seracchioli et al, 2006). From the other side Campo et al, found no ectopic in their series after laparoscopic myomectomy (Campo et al., 2003). None of the ectopic pregnancies developed in the scar of the previous myomectomy.

Previous Caesarean scar (CSP)
Cesarean scar pregnancy carry the high risk of uncontrollable bleeding requiring hysterectomy, so management has to include this risk in its treatment options. Wang et al, described a heterotopic pregnancy combined with intrauterine pregnancy after IVF (Wang et al., 2007). Embryo reduction was performed with transvaginal ultrasound guided KCL injection (0.2ml) at 10 wks gestation. A mass 3x3 cm remained till 32 wks gestation A male was delivered at 35 weeks delivered by CS. Remaining gestational tissue leads to massive blood loss after CS, blood transfusion and bilateral internal iliac arteries ligation.
Another author (Wang et al., 2010) found a Cesarean Scar pregnancy (within the isthmic area of the lower anterior wall of the uterus) and an intrauterine pregnancy after IVF. At this time, management was performed by hysteroscopy evacuation at 7 wks gestation and coagulation of the implantation vessel site. Cervix was dilated to 11 mm, not beyond the endocervical canal and gestational sac was pulled out, under sonographic guidance. Suction curettage was used to clear the residual gestational tissue and a hysteroscopic rolling ball was used to stop the bleeding point. A healthy infant delivered by Cs at 39 wks gestation. From the other side two different cases was presented by Chueh et al., 2008. Both cases were a twin cesarean scar pregnancy. Ectopic pregnancies were treated either by laparotomy excision of the scar twin pregnancy (first case) and hysterosocpic resection (second case) with resectoscopic coagulation of placenta bed vessels. In both cases, no fluid was seen in the cul-de-sac. More pregnancies could be observed in cesarean scar. Litwicka et al, described a triplet heterotopic cesarean scar pregnancy after IVF, a twin pregnancy in the anterior isthmic wall close to the CS scar (separated from the bladder wall by a thin myometrial layer) and one intrauterine gestational sac (Litwicka et al., 2010). Caesarian scar gestation sacs have been diagnosed,one week later than the intrauterine sac. Transvaginal ultrasound-guided potassium chloride (2 ml) and methotrexate (15 mg) was injected in the ectopic gestational sacs while the intrauterine pregnancy continue to ongoing pregnancy. In another case, described by Hsieh et al, a heterotopic triplet pregnancy was evident after IVF treatment, two intrauterine pregnancies and one cesarean scar pregnancy (Hsieh et al., 2004). Color Doppler sonography revealed proliferated peritrophoblastic vessels around the Caesarean scar pregnancy and the intrauterine twin pregnancy. CSP was treated with embryo aspiration under vaginal ultrasonography with preservation of intrauterine twin pregnancy. Due to preterm labour, two infants delivered at 32 wks gestation. Rare CSP may exist at different forms after IVF treatments and previous CS. The management of these pregnancies may be performed with laparotomy or hysteroscopic resection of CS ectopic tissue after KCL lethal injection to embryo. Also MTX may be used for the second case. Complications of the second treatment include spontaneous abortion and congenital abnormality of MTX or diffuse of KCL in the target amniotic sac that may lead to diffuse to adjacent sac.

Live twin pregnancy in the same fallopian tube
A left fallopian tube twin pregnancy was presented by Atabekoğlu et al., an isthmic pregnancy and another ampullary sac in the same tube (Atabekoğlu et al., 2009). Both treated with a left laparoscopic salpingectomy.

Cul-de-sac pregnancy
A case of a cul-de-sac ectopic pregnancy after IVF, was described by Shih et al. (Shih et al., 2007). After 4 weeks from ET it was found an ectopic gestational sac with fetal heart beat in the left adnexa. It was revealed, by laparoscopy, an ectopic mass in the congenital blind pouch that was connected to the posterior cul-de-sac. Laparotomy was used for removal of conceptus and homeostasis.

Hepatic pregnancy
Although a lot of case reports exist for a hepatic pregnancy in the literature (Chin et al., 2010;Moores et al., 2010), none of them is reported after IVF, so they mentioned as primary www.intechopen.com Ectopic Pregnancy -Modern Diagnosis and Management 64 hepatic pregnancy. Chlamydia infections may involved also in this type of ectopic because adhesions between and liver the diaphragm (Fitz-Hugh-Curtis Syndrome) were demonstrated in 34% of those with EP (Picaud et al., 1991). Treatment of this type of pregnancy included direct methotrexate injection (Nichols et al., 1995), laparoscopic suctioning and homeostasis (Chin et al., 2010) or laparotomy. In case an advanced week's live pregnancy is diagnosed, then laparotomy with intact placenta may be performed (Shukla et al., 1995).

Intrauterine and twin bilateral tubal pregnancy
Pan et al, report a case of bilateral tubal pregnancy and intrauterine pregnancy (Pan et al., 2002). After right tubal embryo transfer (due to cervical stenosis) of four embryos, in 5 th week, a laparotomy showed a ruptured right tubal pregnancy, hemoperitoneum and a dilated left tube. Bilateral salpingectomy was performed with preservation of intrauterine pregnancy and deliver of a male at term.

Intrauterine and interstitial heterotopic pregnancy after bilateral salpingectomy
Patient had two previous unsuccessful IVF cycles and removed both tubes for bilateral hydrosalpinges. After that she preformed a third IVF cycle. She developed an intrauterine pregnancy and an interstitial pregnancy that ruptured at the left salpingectomy site by its lateral position to the insertion of the ipsilateral round ligment. After laparotomy and left cornual resection, intrauterine pregnancy survived two more weeks and miscarried. Trisomy 21 was revealed, in aborted fetus (Dumesic et al., 2001).

Cornual pregnancy
Two studies exist that describe cornual pregnancy after IVF. First case was a heterotopic triplet pregnancy after in utero transfer of three embryos (Divry et al., 2006). Cornual pregnancy was treated with resection by laparotomy. A special technique was presented in this patient. A Vicryl string with a tight knot was inserted at the base of the implantation site of the corneal pregnancy and the base of the uterine wall above this string was sectioned. Cornual scar was closed with same stitches in X form while a base knot left in place. Intrauterine twin pregnancy continue uneventfully till 31 wks gestation, where the patient delivered two girls with Csection. The site of the corneal pregnancy was well vascularrized and not ruptured. The second case was a recurrent spontaneous cornual pregnancy 2 years after a heterotopic cornual pregnancy occurred after IVF cycle (van der Weiden et al., 2005). Previous cornual heterotopic pregnancy was treated with injection of 0.5 ml of 15% potassium chloride into the fetal heart while normal pregnancy was delivered at 39 weeks of gestation by elective caesarean section. Spontaneous cornual pregnancy was treated by injection of 40 mg methotrexate in the gestational sac and systemic methotrexate (1.0 mg/kg orally alternated with 15 mg folinic acid).

Interstitial pregnancy
Berkes et al., reported a unilateral triplet ectopic pregnancy, on a woman with a history of right salpingectomy (Berkes et al., 2008). After IVF, in the left fallopian tube, a triplet pregnancy was found (two pregnancies at interstitial and one at ampullary location). Color flow Doppler sonography revealed intensive perithrophoblastic blood flow around the two gestational sacs with live embryos while TVS showed threegestational sacs,in the left interstitial area,in the isthmic part of the fallopian tube and in the ampullar part next to the left ovary. After multiple dose of methotrexate, hCG levels were lowered but pregnancies were ruptured, so a laparotomy was performed with the removal of the left tube and cornual part of the uterus. Another case of previous bilateral salpingectomy and IVF was reported by Chang et al. (Chang et al., 2003). An intrauterine monozygotic twin and an interstitial monozygotic twin pregnancy were reported. By laparotomy, interstitial pregnancy was removed and intrauterine pregnancy allowed delivering at 38 wks gestation. Another intrauterine monochorionic diamniotic twin pregnancy and an interstitial pregnancy were reported by Nikolaou et al. (Nikolaou et al., 2002). Also after bilateral salpingectomy and IVF, interstitial heterotopic pregnancy was developed that ruptured (Dumesic et al., 2001). A recurrent interstitial pregnancy in uterine horn was seen after IVF (Muzikova et al., 2003). Laparoscopic loop ligature was used by Qin et al, for heterotopic interstitial pregnancy (Qin et al., 2008). Perez et al., reported medical therapy in two cases of interstitial pregnancy, one with transvaginal ultrasound guided injection of methotrexate and second with potassium chloride into the ectopic sac of the heterotopic twins (Perez et al., 1993). Overall, interstitial pregnancies are always possible after tubal occlusion. Korkontzelos et al., reported the co-existence of ovarian hyperstimulation with ascetic fluid accumulation, enlarged ovaries after IVF and a right tubal ectopic pregnancy (Korkontzelos et al., 2006). Right salpingectomy was performed. Same case was presented by Fujii et al., which ended in a bilateral salpingectomy and continuation of intrauterine pregnancy till 32 wks of gestation (Fujii et al., 1996).

Consecutive recurrent ectopic pregnancies
Three consecutive recurrent pregnancies have been reported in the same patient with pelvic inflammatory disease, two in the right fallopian tube and one in the left. Laparotomy was performed in all three cases, to preserve the tubes while removing conceptus (Adelusi et al., 2003). Another case of two consecutive ectopic pregnancies after IVF, was presented by Abu- Musa et al. (Abu-Musa et al., 2002). Three consecutive cases of ectopic pregnancy on the same patient was presented by Oki et al., 1998. The first involved simultaneous intrauterine and left tubal pregnancy, the second was a right tubal pregnancy, and the third was a right interstitial pregnancy. Another case of two ectopic pregnancies in consecutive menstrual cycles was presented by Irvine et al. (Irvine et al., 1999). Left distal ectopic pregnancy was seen and treated with left partial salpingectomy while in the next cycle a right distal ectopic pregnancy was observed which treated with right partial salpingectomy. Except the second case, the other two patients conceived by coitus, so cases are presented in this review because they are rare. Another report of recurrent cornual ectopic pregnancy has been presented (MacRae et al., 2009) but presentation is beyond the scope of this manuscript.

Section 5 8.1 Cost effectiveness 8.1.1 Chlamydia trachomatis -ectopic pregnancy-cost effectiveness
Eight studies described cost-effectiveness of Chlamydia screening for pregnancy complications, including ectopic pregnancy. For most of them, proactive screening of 66 Chlamydia is not cost-effective when tested in general population (Buhaug et al., 1989;Roberts et al., 2007;van Valkengoed et al., 2001) and that only when women aged 18 to 24 years old tested or prevalence of Chlamydia is over 3% (Postma et al., 2000) or 2% (Trachtenberg et al., 1988), cost-effectiveness exist for prevention of ectopic pregnancy. Hu et al, pointed out that annual screening for Chlamydia is indicated for women 15 to 29 years of age and selective targeting with semiannual screening of those women with a history of infection (Hu et al., 2004). Partner treatment should be provided (Postma et al., 1999) to avoid re-infection. Another author (Schiøtz et al., 1991) found that routine post-treatment control of non-systematic genital Chlamydia infection is not cost-beneficial.

Ultrasound for diagnosis of ectopic pregnancy-cost-effectiveness
In an emergency department, to rule out the possibility of ectopic pregnancy, the most cost effective strategy is to screen all patients with first trimester bleeding and lower abdominal cramping with ultrasound (Durston et al., 1999), even if the scan is performed by an emergency doctor. Obviously this technique is not cost-effective in symptoms free women (Mol et al., 2002).

Laparoscopic treatment for Ectopic pregnancy-cost effectiveness
When laparoscopy is compared with methotrexate for its cost savings, methotrexate saves about 1000, Canadian dollars (Yao et al, 1996). In a decision and cost-effectiveness analysis, Seror et al., found that first line treatment with methotrexate is more cost-effective than conservative laparoscopy and radical laparoscopy in sub-acute ectopic pregnancy (Seror et al., 2006). Conservative laparoscopy was more cost-effective than radical laparoscopy in this group of patients, in terms of fertility preservation. Methotrexate treatment effectiveness was increased when diagnostic ultrasound accuracy is increased. If patient after an IVF ectopic pregnancy treated with methotrexate, then, in the next cycle, similar ovarian stimulation characteristics could be obtained (Orvieto et al., 2007).

Conclusion
In this systematic review we presented the most important studies dealing with ectopic pregnancy after in vitro fertilization. Also, important biological factors that play a role for EP has been presented. Case reports of ectopic pregnancies their position in the uterus, and the steps undertaken to preserve intrauterine pregnancy has been described. Complications of these treatments, where available, have been mentioned. Practices during in vitro fertilization treatment and their controversial role for this pregnancy complication have been described. Overall, cost-effectiveness studies in the ectopic pregnancy prediction and management has been described. New research directions have been pointed out. Although ectopic pregnancies and more specific heterotopic pregnancies are rare, these increase due to infertility treatment. Active and aggressive management of hydrosalpinx has been proposed for heterotopic pregnancy minimization after IVF. All combinations of heterotopic pregnancies have been described. The major complication was bleeding and rupture of pregnancy. Care was taken for intrauterine pregnancy continuation but many cases miscarried after some time. Laparoscopy and hysteroscopy were methods of choice but laparotomy was chosen when threat of major bleeding was expected. Another method of treatment was vaginal aspiration of embryo sac after a lethal injection with a pharmacological agent. Most cases have not recognized till rupture of ectopic pregnancy.

Ectopic Pregnancy and Assisted Reproductive Technologies: A Systematic Review 67
The majority of studies were case report and retrospective studies. Even if more studies exist in a specific issue (e. g. ectopic pregnancy rates in fresh and frozen IVF cycles) these are not, homogenously designed, and no data synthesis could be made. Also in the management of heterotopic pregnancies, a single methodology was not used, so no best practices outcome could be formed. Screening for ectopic pregnancy show better cost-effectiveness only when we expect increased prevalence of this entity (Roberts et al., 2007;van Valkengoed et al., 2001) or women age from 18 to 24 years old (Buhaug et al., 1990). Also general population screening program for C. Trachomatis, show that costs exceeds the benefits to avoid ectopic pregnancy. The method of choice for treatment is laparoscopy, because show similar costeffectiveness but less invasiveness (Gray et al., 1995) than laparotomy. Combination therapies, like uterine artery embolization and laparoscopy has been used for complications like hemorrhage. Although these therapies are expensive, the rare cases do not allow a costeffectiveness analysis to be performed. Many heterotopic pregnancies were identified after EP rupture, thus leading to a laparoscopy or laparotomy and possible complications while an early identification may lead to MTX therapy, that is by far a more cost-effective treatment strategy. From the other side, close ultrasound monitoring has revealed heterotopic pregnancies developed in previous Caesarean scar pregnancy, cervical pregnancies etc. So for IVF patients, more intense ultrasound and b-hCG monitoring is required. It is not known yet whether this applies to all patients that had an ET or only in the subgroup of patients with risk factors for EP undergoing ET. Many ectopic pregnancies remained unidentified with viable pregnancies till second trimester. It is important, for these cases, to improve our detection capabilities with new approaches. Heterotopic pregnancy may present with different combinations and uterine locations, at various gestational ages, even when the intrauterine pregnancy aborts. Eventually the presence of an intrauterine gestation sac in a patient without symptoms should not exclude the diagnosis of a concomitant extrauterine pregnancy until the pelvis is carefully visualized (Rizk et al., 1991). Currently, no biomarker could early identify an ectopic pregnancy, especially a heterotopic one. A promising non invasive marker could be developed from the use of cervical trophoblastic cells and special markers on them. Regarding the IVF procedure, infertility medication should be used cautiously from nonspecialists and ovulation induction has to be preformed always under close monitoring. In case of altered tubal motility, close monitoring of pregnancy as evolves, should be performed. Chlamydia infections and tubal factor infertility still remain the major factor for EP after IVF. Active management for hydrosalpinx seems to lower EP rates, but still no minimal invasive test exists. No other IVF technique could be accounted for increased ectopic pregnancy rates except the transfer of multiple embryos, especially more than two. Where indications exist for increased EPs after specific techniques (e. g. assisted hatching), more clinical trials should be performed, controlled also for EP factors. Tubal transfer techniques (ZIFT) have been abandoned through years, so they could not account for EP in the modern era. Tubal reanastomosis also is not practiced in all IVF clinics, and only where it is practiced it has to be considered as a factor of tubal pregnancy. Another issue that needs to be checked is the association of ectopic pregnancy and the abnormal embryogenesis. This is important for male factor infertility and increased age. It is not clear yet whether more intense pregnancy monitoring should apply in these patients.
As a general policy, individual IVF practices should evaluate their EP rate in an attempt to identify factors that may increase or decrease the rate compared to national statistics . It is not clear yet, whether a single biological pathway should account for ectopic pregnancy. Although TB implantation mechanism is different from normal uterine mechanism, tubal pregnancies should be used to study embryo implantation. Invasive pathway, as described in ectopic pregnancy seems to be important. Another pathway that may be involved is the NO pathway that is altered through the Chlamydia infection altered immune response. Researchers performing RCTs in ectopic pregnancies need to consider certain issues in their design. Patients differ in age and the infertility factor. A trial has to control for the number of embryos transferred, the quality of them and patients demography because a common underlying risk factor might exist. A clear measure of complications has to be developed, especially for cost effectiveness studies. Because ectopic pregnancies after IVF always need intervention, no placebo trials could be performed. Length of follow up and follow up plan need to be decided before hand, so pregnant women need to have standardized care. Level of training for the providers of IVF services seems to be important. Ruptured ectopic pregnancies may present with severe complications, due to hemorrhage. Currently, no single treatment plan is chosen and different groups perform different approaches. Although these treatments are life saving, they are not cost effective. It is important for hospitals with large IVF groups to undertake such studies, so knowledge to be transferred to smaller groups. In case of heterotopic pregnancy, it is important to know how to protect the intrauterine embryo (as valuable pregnancy), so research should direct to this also.