(USMLE topics, gynecology) Mechanism of action of the Pill. This video is available for instant download licensing here :
Prevent pregnancy. they contain hormones that is the combination pill which contains both progesterone. these 2 hormones interfere with the menstrual cycle refers to the monthly events that occur within a woman’s body in preparation for the possibility of pregnancy. each month, process called ovulation. at
The same time, pregnancy. if fertilization does not take place, the lining of the uterus is shed in menstrual bleeding and the cycle starts over. the menstrual secreted by the hypothalamus, pituitary gland, and ovaries. basically, the hypothalamus produces gonadotropin-releasing hormone, gnrh; the
Pituitary secretes follicle-stimulating hormone, fsh, and luteinizing hormone, lh; while the ovaries produce estrogen and progesterone. these hormones are involved in a regulatory network that results in monthly cyclic changes responsible the 2 hormones that are required for ovulation mature egg; and lh, which is responsible
For ovulation event itself. two other hormones, estrogen and progesterone, are at high levels after ovulation, in the second half of the cycle. they suppress fsh and lh during this time, preventing the ovaries from releasing more eggs. if fertilization occurs, estrogen and progesterone levels remain high
Throughout pregnancy, providing a continuous suppression of ovulation. on the other hand, in the absence of pregnancy, the levels of estrogen and progesterone in tricking the ovaries into thinking that ovulation has already occurred; fsh and lh are constantly the pills are taken every day for three weeks,
Followed by one week of placebo pills containing no hormones. during the week of placebos, estrogen and progesterone levels fall, triggering a so-called withdrawal bleeding, or fake indication that fertilization did not happen, but it is not required for birth control. in fact, there exist continuous-use contraceptive
Pills with less or no placebos, resulting in less or no menstrual periods. these pills are particularly beneficial for women who suffer from menstrual disorders such as excessive menstrual bleeding, for lactating women, or those who cannot contain only progestin. these are not as ovulation. their effect
Relies more on the ability of progestin to promote secretion of a thick cervical mucus to obstruct sperm entry.
Transcribed from video
How Birth Control Pills Work, Animation By Alila Medical Media