Contraceptive Patch

Contraceptive Patch, small, plastic skin patch for women that releases low doses of female sex hormones to prevent pregnancy. The square-shaped patch measures 4.45 cm (1.75 in) on each side and contains estrogen and progestin (a synthetic form of progesterone). This hormone combination is similar to that used in some types of birth control pills, and it works in a comparable fashion to prevent pregnancy by inhibiting the ovaries from releasing an egg, thickening the mucus of the cervix (opening of the uterus) to prevent sperm from reaching an egg, and preventing the lining of the uterus from thickening so that a fertilized egg cannot implant. Marketed under the brand name Ortho Evra, the patch has been available by prescription since early 2002. With typical use this method of birth control is 95 to 99 percent effective in preventing pregnancy.

In February 2006 the United States Food and Drug Administration (FDA) advised women using the patch to consult with their physicians after preliminary results from a study found that women using the patch had a higher risk for blood clots than women taking the pill. Current warning labels on the Ortho Evra patch note that women using the patch receive 60 percent more estrogen than those who use birth control pills. Women who smoke should not use the patch because of increased risk of stroke and heart attack, according to health officials.

A woman applies a new contraceptive patch once a week for three out of four weeks. No patch is worn during the fourth week and the woman’s menstrual period usually starts during this week. One week after removing the last patch the woman applies a new patch, even if she is still bleeding from her period. This three-week on and one-week off pattern is repeated every month to provide continuous protection against pregnancy.

To apply a contraceptive patch, a woman places the adhesive side of the patch to clean, dry skin on the lower abdomen, the buttocks, the front or back of the upper body (but not the breasts), or the upper outer arm. It should not be applied to areas of the skin where makeup, lotion, or powder may be used, as these interfere with the patch’s ability to adhere. To reduce the chance of skin irritation, each new patch can be applied to a different area of the body. Once attached, the patch should be pressed in place for at least 10 seconds to ensure that it is firmly adhered.

After the patch is applied, it should not be moved to another area of the skin because this may lessen its ability to stick to the skin. If a patch becomes loose or falls off for more than 24 hours, or if a patch is used for more than one week, the risk of becoming pregnant increases. Under these circumstances, a barrier method of birth control, such as a condom, diaphragm, or cervical cap, should be used during sexual intercourse.

Most women find the contraceptive patch easy to use. It prevents pregnancy for only one month at a time, so its effects can be reversed quickly. Regular use of the patch may result in shorter, more regular menstrual periods, while also decreasing premenstrual cramping and menstrual-related iron deficiency and acne.

In some women the contraceptive patch irritates the skin at the site of application. It may also cause irregular bleeding, weight gain or loss, breast tenderness, nausea, vomiting, headache, and mood changes for the first two to three months of use. Women who wear contact lenses may find that their lenses become uncomfortable or they may experience a vision change. The patch is less effective in women who weigh over 90 kg (198 lb).

The patch does not protect against sexually transmitted infections, including human immunodeficiency virus (HIV), which causes acquired immunodeficiency syndrome (AIDS). In addition, the patch increases a woman’s risk of developing blood clots or suffering from a heart attack or stroke. Women over 35 who smoke have a greater chance of developing these conditions and should not use the patch. Women also should not use the patch if they have high blood pressure, breast or uterine cancer, liver disease, a history of heart problems, or uncontrolled diabetes. Some medications, including antibiotics and antiseizure, tuberculosis, and migraine drugs, can interfere with the effectiveness of the contraceptive patch.