In the 1960s, the U.S. Food and Drug Administration approved a contraceptive that allowed women to plan desired pregnancies and prevent unwanted pregnancies. Oral hormonal contraception ('the pill') uses synthetic hormones similar in structure to progesterone and/or estradiol. What is the pill's mechanism of action? Use Table 47.2 to compare and contrast the mechanisms of action of emergency contraception and mifepristone to that of the pill. Which methods act as contraception and which act to terminate a pregnancy? Explain.

Video transcript

Welcome back. Let's look at the next problem here. It says blank is a derivative of the synthetic progestin. North and drone with anti progesterone activity. So the proper answer here is Choice C. Mythic Stone, a progestin is a molecule a synthetic molecule that mimics progesterone and therefore it competitively binds two progesterone receptors. As a result it inhibits the activity of progesterone. Therefore it inhibits progesterone activity. Um And since progesterone and pregnancy maintains the uterine lining and prevents theaters from contracting, there's a major role in maintaining pregnancy. It's produced by the corpus ludie um at the very earliest stages of pregnancy and then the placenta takes over. So something that competitively binds the progesterone receptor and that inhibits the effects of progesterone um is used and combination with MR. Crystal to bring about um medical abortion and to manage early miscarriage. Since it inhibits that progesterone activity. So again our answers. Choice C. But let's just look through the other answer choices. Prostaglandins are a major part of the inflammatory response. Um They also help the cervix to dilate and contractions to occur. So they do have an important role in induction of labor but not the answer we're looking for here estrogen of course is the major female sex hormone involved in stimulating ovulation, regulating the menstrual cycle and development of female sexual characteristics but not what we're looking for here. And finally. Choice D testosterone is of course the major male sex hormone responsible for the development of secondary sexual characteristics in males and in development production of sperm and the male sexual drive. So not our answer here again, we have Choice C. Mifepristone is a derivative of synthetic progestin Northen drone with anti progesterone activity. See you in the next video.