Hormones are a type of natural chemicals secreted by certain cells in the body. They are transported by blood circulation to target organs to exert their effects. The word \”hormone\” comes from the Greek word, which means to stimulate and stabilize emotions. The main functions of hormones are: regulating the menstrual cycle and the body\’s metabolism; promoting sexual maturity; maintaining pregnancy and regulating other physiological functions in the body.
After mastering the cyclic changes of hormones in the body, you will find that hormones may be factors affecting fertility. The menstrual cycle is regulated by 6 hormones, and the interaction between them forms an orderly chain reaction. Under the regulation of the gonadal axis, these hormones rise and fall at different times in the menstrual cycle. For the convenience of description, the menstrual cycle is taken as 28 days as an example.
Estrogen is mostly secreted by the ovaries, and its main physiological function is to promote the growth and development of female sexual organs. In the first 14 days of the menstrual cycle, this hormone is dominant and causes the endometrium to proliferate and thicken, and breast tissue to proliferate and develop. It also stimulates the proliferation of hair-like ciliated cells in the fallopian tube to facilitate the relative movement of sperm and eggs and fertilization. At the same time, it also has the effect of promoting the secretion of mucus from the endocervical glands to lubricate the vagina, facilitate the movement of sperm and enhance the antibacterial ability of the vagina. In the middle of menstruation, estrogen levels reach their peak and the pH of cervical mucus is alkaline, providing the best microenvironment for sperm survival.
Progesterone is also a hormone secreted by the ovary. Progesterone is dominant in the last 14 days of the menstrual cycle, that is, after ovulation; it thickens the endometrium and further promotes the growth of ciliated cells in the fallopian tube ( Both estrogen and progesterone can stimulate the secretion of fallopian tube mucus and muscle contraction, causing some women to experience pinprick-like pain on one side of their abdomen during mid-menstruation, which is also called intermenstrual pain). In the second half of the menstrual cycle, progesterone thickens the cervical mucus and makes the pH acidic, which is not conducive to the retention and survival of sperm. In addition, progesterone slows estrogen-induced vaginal epithelial growth and makes breasts fuller and more pliable.
Follicle-stimulating hormone-releasing hormone (FSH-RH) is secreted by the hypothalamus located at the base of the brain (the human body’s hypothalamus is also called the control center of the endocrine system. It not only regulates the reproductive system, but also regulates sexual desire. , hunger, fullness, thirst, sleep and other functions). The hypothalamus is sensitive to physical and mental diseases. It transmits information through the endocrine system to protect the menstrual cycle from interference by factors unrelated to the reproductive system as much as possible. During the first few days of the menstrual cycle, when estrogen and progesterone are at their lowest levels, they stimulate the hypothalamus to secrete follicle-stimulating hormone.The hormone, follitropin-releasing hormone, causes the pituitary gland to secrete follicle-stimulating hormone.
Follicle-stimulating hormone (FSH) is secreted by the pituitary gland. The pituitary gland is located under the hypothalamus and secretes hormones with a variety of regulatory functions, such as thyrotropin to regulate metabolism; prolactin to regulate milk secretion; and oxytocin to promote uterine contractions. Follicle-stimulating hormone promotes the proliferation of granulosa cells around oocytes, thereby increasing the levels of estrogen and progesterone.
Luteinizing hormone-releasing hormone (LH-RH) is secreted by the hypothalamus. In the middle of menstruation, when estrogen levels reach their highest peak, the hypothalamus secretes luteinizing hormone-releasing hormone in feedback, triggering the pituitary gland to release luteinizing hormone to stimulate ovulation.
Luteinizing hormone (LH) is secreted by the pituitary gland under the stimulation of luteinizing hormone-releasing hormone in the hypothalamus. It stimulates the occurrence of ovulation, causing the ovaries to release unfertilized eggs into the fallopian tubes (the fallopian tubes are where sperm and eggs combine). The corpus luteum forms after follicle rupture. 8 to 12 days after ovulation, the corpus luteum continues to secrete estrogen and progesterone (progesterone is dominant). At the end of menstruation, if the egg is not fertilized, the corpus luteum shrinks rapidly, and estrogen and progesterone also decrease accordingly. When estrogen and progesterone drop to extremely low levels, the endometrium that proliferates under the action of estrogen is no longer needed for fertilized eggs, so the endometrium is peeled off and menstruation begins.
Endocrine disorders account for 50% of the causes of infertility. Any factor that affects the interaction between hormones may disrupt the menstrual cycle and thus affect conception. These factors include systemic illnesses such as high fever and mental stress. Therefore, a normal and regular menstrual cycle is a sign of good health for women.
If the hypothalamus does not respond to low levels of estrogen and does not secrete follicle-stimulating hormone or luteinizing hormone-releasing hormone, then the pituitary gland will not secrete follicle-stimulating hormone or luteinizing hormone, Ovulation will not occur and conception will not occur. Common causes are: influence on the hypothalamus or pituitary gland, anorexia nervosa, extreme physical training, etc.
High or low estrogen and progesterone levels caused by ovarian dysfunction can also affect pregnancy.
Certain drugs, especially sedatives and mood-regulating drugs, can affect the menstrual cycle without passing through the hypothalamus, thereby preventing pregnancy. After stopping the drug, the ability to conceive can return to normal.
This article is provided by Baidu Reading and is excerpted from \”The Clear \”Conception\” Plan\” Author: Sun Jianqiu and Xie Yingbiao