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The maternal immune system during pregnancy
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Placental hormones appear to play a role in immune function during pregnancy. The hCG can inhibit mitogen-induced T-cell and T-cell-dependent B-cell responses (145–149). These actions appear to be accomplished directly through T-cell hCG receptors (150), but further delineation of this mechanism is still the subject of ongoing investigation.
Basic medicine: physiology
Published in Roy Palmer, Diana Wetherill, Medicine for Lawyers, 2020
The gonads comprise the ovaries in the female and the testes in the male. Each gonad has a dual function: to produce germ cells, i.e. ova and spermatozoa, and to secrete sex hormones. Pituitary hormones (gonadotropins) cause enlargement of the ovary and testis during childhood, and the resultant release of gonadal hormones brings about the changes of puberty, including the growth spurt and the secondary sexual characteristics of females and males. Oestrogens and progesterone secreted by the ovary cause girls to start their monthly cycle of ovulation and menstruation, while testicular androgens stimulate the production of fertile sperm and seminal fluid. If sexual intercourse takes place during the period following ovulation, when an ovum is shed from the ovary and passes down the female genital tract, then conception may take place as the sperm penetrates the ovum. The developing embryo implants into the wall of the uterus, leading to the formation of the placenta, and placental hormones then sustain the pregnancy. At birth, which occurs around 270 days later, pituitary oxytocin governs the onset of uterine contractions. The breasts have enlarged during pregnancy under the combined actions of oestrogen, progesterone and the pituitary hormone prolactin. After birth lactation is controlled by prolactin combined with oxytocin secreted as a reflex response to suckling by the infant.
Summation of Basic Endocrine Data
Published in George H. Gass, Harold M. Kaplan, Handbook of Endocrinology, 2020
The placenta takes care of the food and waste exchange between fetus and mother. It is also an endocrine gland. The hormones secreted are estrogens, progesterone, and the anterior pituitary polypeptide and protein hormones, which include hCG and human chorionic somatomammotropin (hCS; also called placental lactogen [hPL]); hCS consists of a single polypeptide chain containing 191 to 199 amino acid residues. Other placental hormones are also produced.
Anti-Mullerian hormone levels in spontaneous pregnancies with hyperemesis gravidarum
Published in Journal of Obstetrics and Gynaecology, 2022
Banuhan Şahin, Gizem Cura Şahin, Andrea Tinelli
The HG incidence is highest at the beginning of pregnancy when hormones are produced by the placenta and the corpus luteum and, therefore, it has been emphasised that endocrine factors are potentially involved in the HG development. In fact, circulating ovarian and placental hormones are strongly associated with the increasing serum level of human chorionic gonadotropin (hCG) from the very beginning of pregnancy, and it is high influent in the HG pathophysiology (Lagiou et al. 2003). Both high and low progesterone concentrations have been shown to contribute to the HG development (Kleine et al. 2017). Oestrogen continuously increasing throughout the pregnancy could play a role in HG pathogenesis, since HG is more common in obese women and in the first trimester, where oestrogen levels are very high (Goodwin et al. 1992). In a study on the HG aetiology, Taşkın et al. reported that cellular immunity was activated by high oestradiol and high progesterone levels (Taşkın et al. 2009). As reported in the literature, the authors’ study showed that serum oestradiol and progesterone levels were higher in pregnant women with HG diagnosis than in the control group, but the difference did not reach a statistical significance.
Features of the 1st trimester of pregnancy course with severe deficiency of 25(OH)D
Published in Gynecological Endocrinology, 2021
M. Bakleicheva, O. Bespalova, I. Kovaleva
A generally accepted indicator of the internal micronutrient composition of the environment is vitamin D, which through its complex multifactorial action has a beneficial effect on metabolic and immune processes in the mother’s body [1,2]. In the early stages of pregnancy, the trophoblast simultaneously produces and responds to the effects of vitamin D, which has a local anti-inflammatory response and, in parallel, induces the growth of decidual tissue for a successful pregnancy [3,4]. There is evidence that 1,25(OH)2D regulates the release and secretion of human chorionic gonadotropin in syncytio-trophoblast and increases placental production of sex steroids. There is evidence that calcitriol promotes the transport of calcium to the placenta, stimulates the release of placental lactogen, and also regulates the expression of HOXA10 (a gene that determines the development of genital organs) in stromal cells of the human endometrium [4]. Expression of HOXA10 is of some importance for endometrial development and improves susceptibility to implantation. Taken together, the evidence suggests that 1,25(OH)2D helps implant and maintain normal pregnancy, supports fetal growth through calcium delivery, controls the secretion of several important placental hormones, and limits the production of proinflammatory cytokines [5,6].
Childbearing age is correlated with components of metabolic syndrome and parameters of insulin resistance in Chinese menopausal women
Published in Gynecological Endocrinology, 2021
Danping Zhu, Fang Fang, Xia Zhang, Rui Han, Fang Liu, Hang Wang
Childbearing age is a factor of MS that has rarely been directly researched. Previous studies have indicated that parturition is associated with MS. Childbearing has a graded direct association with the prevalence of MS later in life, which is not independent of obesity [21–23]. The adjusted relative risk of MS was 1.33 for one birth compared with 0 births, and the risk was enhanced with parity. MS was greatly associated with weight gain occurring as a consequence of childbearing [17,20]. Few studies have directly investigated the relationship between childbearing age and MS. Most researchers believe that abdominal obesity and IR are the central links in the pathogenesis of MS. As a normal response to pregnancy, the physiological role of IR is to increase the levels of sugar, fat, amino acids and other factors in maternal blood circulation to meet the requirements for fetal growth [24]. However, IR also has adverse effects on pregnant women, such as decreased glucose uptake and oxidation, which promotes the decomposition and oxidation of fats and reduces protein use. The definitive mechanism underlying how normal pregnancy induces IR is unknown. Some researchers believe that IR results from multiple factors working together, such as the secretion of placental hormones and adipocytokines (e.g. human placental lactogen, HPL), human chorionic somatomammotropin (HCS), adiponectin, and leptin [24,25].