The Pill is designed to interfere with several normal functions of fertility in order to make a woman 1) unable to conceive due to temporary sterility or sperm immobility, and/or 2) unable to carry a pregnancy to term (an early abortion).
This process can be accomplished in various ways.
Suppressing Ovulation: When a woman ovulates, hormones released from the pituitary , a gland located at the base of the brain, stimulate her ovaries to ripen and release an egg. The combination pill usually interrupts the release of these pituitary hormones resulting in no egg being released from the ovary, thus preventing pregnancy from occurring. With no egg available for fertilization, the woman is chemically sterile. The progestin-only pill, however, has a weaker effect. It generally does not suppress ovulation.1
Inhibiting Implantation: Another important aspect of fertility is the process by which the lining of the uterus is replenished and maintained. After an egg is fertilized, it normally implants in this lining (endometrium), drawing nourishment and sustenance. The progestin component of the combination pill and the progestin-only minipill cause the inner lining of the uterus to become thin and shriveled, unable to support implantation of the embryo(newly fertilized egg).2
Impeding Sperm Migration: Preceding ovulation, a woman’s cervix produces a watery mucus through which sperm swim to meet the egg. The mucus also provides nourishment to sustain the life of the sperm cells. This mucus thickens under the influence of a progestin and so impedes sperm migration.3
Bookmarks