Hormones in Human Reproduction

• Hormones are secreted by glands in the endocrine system.
• During puberty, hormones create changes in physical and emotional characteristics.
• A hormone is a chemical messenger produced in glands and carried by the blood to specific organs in the body.
• An organ or tissue that makes a substance for release, such as a hormone, is a gland.
• Hormonal methods of contraception use hormones to prevent pregnancy.
• Non-hormonal methods of contraception do not use hormones to prevent pregnancy.
• Reproductive technologies, such as infertility hormones, use hormones in connection with fertility treatment.
• Evaluating infertility treatments involves considering the role of reproductive hormones.
• The menstrual cycle is a recurring process which takes around 28 days.
• During the process, the lining of the uterus is prepared for pregnancy.
• If implantation of the fertilised egg into the uterus lining does not happen, the lining is then shed, this is known as menstruation.
• Several hormones control this cycle, including FSH (follicle stimulating hormone), LH (luteinising hormone), oestrogen and progesterone.
• FSH (follicle stimulating hormone) is produced by the pituitary gland and causes an egg to mature in an ovary.
• FSH (follicle stimulating hormone) also stimulates the ovaries to release oestrogen.
• Oestrogen is produced by the ovaries and stops FSH (follicle stimulating hormone) being produced, so that only one egg matures in a cycle.
• Oestrogen repairs, thickens and maintains the uterus lining.
• LH (luteinising hormone) is produced by the pituitary gland and triggers ovulation (the release of a mature egg).
• Progesterone is produced by the ovaries and maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy.
• If a woman becomes pregnant, the placenta produces progesterone which maintains the lining of the uterus during pregnancy and means that menstruation does not happen.