Infection and Infertility
Infection is a multifactorial process, which can be induced by a virus, bacterium, or parasite. It may cause many diseases, including obesity, cancer, and infertility. In this chapter, we focus our attention on the association of infection and fertility alteration. Numerous studies have suggested that genetic polymorphisms influencing infection are associated with infertility. So we also review the genetic influence on infection and risk of infertility.
Part of the book: Genital Infections and Infertility
Environmental Factors and Male Infertility
A significant decrease in human fertility has been observed in the last 50 years. Approximately 15% of couples of reproductive age have fertility problems and about half of these cases are because of male factors. A growing body of evidence suggests that environmental factors play an important role in the causes of male infertility. Our environment is contaminated by natural and synthetic chemicals, which could interact with the endocrine system, resulting in the reduction of human fertility. Studies carried out in recent years have proven that endocrine-disrupting chemicals may disturb fertility of men. Improper lifestyle factors such as smoking, alcohol consumption, high temperature, radiation also have negative impact on male fertility. This chapter is an overview of recent developments about the importance of endocrine-disrupting chemicals and lifestyle factors’ effects on sperm counts and male fertility in human.
Part of the book: Spermatozoa
Smoking: An Important Environmental Risk Factor in Pregnancy
It is generally recognized that smoking has been one of the most public health disorders around the world. Nowadays, more and more studies have proved that smoking during pregnancy is responsible for both maternal and fetal health disorders along with several general health effects. It may lead to various kinds of pregnancy illness and cause risk to the fetus during perinatal stage. After birth, this behavior can also have harmful influences on neonates, and even on children. However, smoking during pregnancy has several adverse effects, the molecular mechanism of it remains unclear. Recently, some studies have proved that it is associated with aberrant epigenetic modifications. All of these remind us that more attention should be paid to maternal cigarette smoking, and more studies should be carried out to confirm the effects and investigate the molecular mechanisms. In this chapter, a brief review is given on the perinatal effects and long-term influences of maternal and passive smoking. We also briefly clarify the epigenetic mechanisms underlying the adverse effects of passive smoking during pregnancy.
Part of the book: Pregnancy and Birth Outcomes
Oxytocin and Pregnancy
Oxytocin, an important neuropeptide, exerts a wide influence on the central nervous system and the peripheral tissues. In the central nervous system, the oxytocin gene expression is mainly shown to be present in neurons in the hypothalamic paraventricular and supraoptic nuclei. Oxytocin gene also transcribes in the peripheral tissues such as uterus, placenta, and amnion. Oxytocin receptors can be founded in many tissues in humans, like the uterine, ovary, testis, kidney, and so on. And just in the same tissue, due to the variation of physiology factors, the amount of oxytocin changes a lot. Oxytocin secretion is closely linked with pregnancy advancing. During labor, the contractions of uterine smooth muscles and oxytocin secretion are inseparable. Moreover, oxytocin is also responsible for stimulating milk ejection after parturition. Oxytocin is associated with many diseases. Poor regulation of oxytocin may cause postpartum depression and infantile autism. In terms of physiology, fatal heart failure and gestational hypertension are concerned with oxytocin level. In this chapter, we will discuss the oxytocin in pregnancy as well as its clinical applications.
Part of the book: Oxytocin and Health
Prenatal Diagnosis: The Main Advances in the Application of Identification of Biomarkers Based on Multi-Omics View all chapters
Prenatal diagnosis is to make the diagnosis of fetal structural abnormalities, genetic diseases, and pregnancy-related diseases before birth thus could offer evidence for intrauterine treatment or selectively termination of pregnancy. Up to now, researchers have applied multi-omics, including genomics, transcriptomics, and proteomics, in the discovery of prenatal diagnostic biomarkers. They have found some candidate biomarkers for aneuploids, preeclampsia, intrauterine growth retardation, and congenital structural abnormalities. With the momentous progress of biomarkers’ identification based on multi-omics for prenatal diagnosis, noninvasive prenatal testing (NIPT) has experienced tremendous progress and is revolutionizing prenatal screening and diagnosis over the past few decades. Extensive studies have also demonstrated the value of biomarkers. In particular, cell-free DNA (cfDNA), allows for a definitive diagnosis in early pregnancy for fetal diseases, including Down syndrome and other common aneuploidies. The cfDNA can be extracted from maternal plasma, posing no risk of miscarriage compared to the traditional invasive diagnosis directly analyzing fetal cells from amniocentesis or chorionic villus sampling. In this review, we would discuss the main advances, strengths, and limitations in the application of biomarkers for prenatal diagnosis along with the analysis of several representative fetal diseases.
Part of the book: Ectopic Pregnancy and Prenatal Diagnosis