A birth control patch is a new method of contraception for women. It is available as a small plastic square patch (Brand name Ortho Evra) that contains the two female hormones, estrogen in the form of ethinyl estradiol and progesterone in the form of norelgestromin.
It acts in the following ways:
It prevents the release of the egg from the ovary
It causes changes in the cervical mucus, thus preventing the sperm from reaching the egg
It changes the inner lining of the uterus, thus preventing implantation of the egg
Though its effect starts immediately after application, an additional contraception is advised for the first 7 days after starting the patch. The patch does not protect the woman from AIDS or other sexually transmitted diseases
The birth control patch is similar to oral contraceptive pills in terms of mechanism of action, benefits and side effects. Its main advantage is that it needs to be changed only once a week
. This avoids the problem of missed doses with the oral pills.
The major problem or disadvantage with the patch is that it can increase the risk of blood clot formation more than the conventional pill.
Hence a careful patient selection is necessary to ensure that the woman will have maximum benefit with least side effects.