The hormone that prevents abortion or expulsion of the foetus during pregnancy is

The hormone that prevents abortion or expulsion of the fetus during pregnancy is progesterone. Progesterone is a hormone that is naturally produced by the ovaries after ovulation. During pregnancy, progesterone is produced in large amounts by the placenta to maintain the pregnancy. One of the key functions of progesterone during pregnancy is to prevent the uterus from contracting and expelling the fetus. It does this by relaxing the smooth muscles of the uterus, which helps to maintain a stable and supportive environment for the growing fetus. Without enough progesterone, the uterus may start to contract, which can lead to a miscarriage or premature delivery. Therefore, progesterone plays a crucial role in ensuring the successful continuation of a pregnancy.