Female hormone

• The consequences of estrogen loss affect all estrogen target organs, including the genitalia, bladder, and brain.
• Longer-term consequences of estrogen loss include impaired cognitive function, wound healing, and immune system function.
• Hormone replacement therapy is widely used to manage both short- and longer-term consequences of menopause.
• Estrogen is a potent anti-inflammatory agent, and its loss can impair the immune system.
• Short-term consequences of estrogen loss include vasomotor symptoms such as hot flashes and night sweats, which are attributed to fluctuations in estrogen levels.
• Exogenous control of the HPO axis allows for timed ovulation and egg collection in preparation for procedures such as IVF.
• Bone density decreases with age and is pronounced in post-menopausal women.
• A range of pharmacological approaches are used to manage female fertility, depending on the diagnosed/suspected causes of fertility.
• Coagulation factors control blood loss locally.
• Exogenous estrogen and progesterone inhibit HPO (higher doses of progesterone alone can also inhibit HPO).
• Withdrawal of sex steroids at the end of the luteal phase leads to the release of prostaglandins, vasoconstriction, tissue hypoxia, connective tissue breakdown, and fragmentation.
• These lesions continue to cycle under hormonal control, but are not lost at menstruation.
• In males, negative feedback only by androgens occurs on GnRH, FSH, and LH.
• GnRH agonists and antagonists are both used in ART to shut down ovary, in advance of controlled cycle.
• Female infertility/subfertility can be caused by anovulation, endocrine disorders (PCOS), uterine receptivity, and reduced oocyte quality.
• Progesterone counters the proliferative effects of estrogen during the secretory phase.
• Exogenous progesterone in ART has multiple actions in preventing pregnancy, including thickening of cervical mucus, thinning of endometrial lining, and inhibiting ovulation.
• Ectopic growth of endometriosis occurs due to 'reflux menstruation', where endometrial tissue fragments shed at menses pass through the Fallopian tube, then become established in ectopic sites.
• Some endometriosis cannot be explained by reflux menstruation, and may arise de novo from progenitor cells in ectopic tissues.
• In females, positive and negative feedback by estrogen occurs on GnRH, FSH, and LH.
• The secretory phase is characterized by continued growth of glands and blood vessels and secretion of glycogen-rich fluids, in preparation for potential embryo implantation, primarily promoted by progesterone.
• Menstruation is the shedding of the superficial layer (functionalis) of the endometrium.
• Endometriosis is the establishment and growth of endometrial tissue outside the uterus.
• Proliferation is the growth of endometrial glands and blood vessels in response to the increase in estrogen.
• Suppression of HPO in ART can be achieved by GnRH agonists and antagonists, or by inhibiting the hypothalamic-pituitary feedback systems.
• Family history is a risk factor for endometriosis.
• Contraception via HPO inhibition in ART can be achieved by exogenous estrogen and progesterone, or by disrupting the endometrium.
• Menstruation is the shedding of the uterine lining due to the decrease in estrogen and progesterone.
• The hypothalamic-pituitary feedback systems are regulated differently in males and females.
• Ovaries are connected to the uterus by Fallopian tubes.
• Fimbriae, at the end of the Fallopian tube, capture the oocytes.
• The ampulla is where the oocyte gets fertilised in the Fallopian tube.
• The menstrual cycle involves differences between anterior pituitary hormones FSH and LH, as well as cyclical variations in oestrogen, progesterone, and ovarian cycle.
• Each month, the development of a mature follicle undergoes ovulation, releasing an oocyte for potential fertilisation and pregnancy.
• The uterine cycle changes in the uterine endometrium lining across the course of the menstrual cycle.
• Follicular phase in the ovarian cycle is followed by luteal phase, after ovulation.
• In the developing follicles, cells proliferate and differentiate into granulosa cells that surround the oocyte.
• Secretion of non-cellular material from granulosa cells forms the zona pellucida.
• Ovarian stromal cells are recruited in response to factors secreted by primary follicle to become theca cells.
• Dominant follicle is selected by day 7 to complete maturation, containing the oocyte that will be released at ovulation.