Sold under the brand name Ortho Evra, the birth control patch is a type of hormonal birth control that requires a prescription. Attached directly to the skin, the birth control patch is worn for three weeks, where hormones are released into the body. The woman removes the patch the fourth week when she menstruates. The American Pregnancy Association states that the patch should be placed in a different area of the body every cycle to prevent skin dryness and irritation.
Effectiveness
The American Pregnancy Association states that when the birth control patch is worn correctly (for three weeks without disruption), it has a failure rate below 1 percent. However, certain factors can decrease the patch's effectiveness, such as if the woman's weight is above 198 pounds, according to Planned Parenthood. Antibiotics, anti-seizure medications and fungal infection medications can also affect how well the patch protects against an unwanted pregnancy.
Hormones
Planned Parenthood states that the birth control patch has a combination of estrogen and progestin, which prevents pregnancy through three mechanisms. First is by suppressing ovulation, which stops an egg from being released from the ovaries. The second mechanism is to thicken the cervical mucus, which acts as a barrier between the egg and sperm. The last mechanism is to thin the uterine lining, which prevents a fertilized egg from implanting in the uterus.
Additional Benefits
Besides preventing pregnancy, the birth control patch also provides a woman additional benefits, according to Planned Parenthood. The estrogen and progestin suppress androgens, thus treating acne. The patch can also decrease premenstrual symptoms, such as menstrual cramps, and help with iron deficiency anemia. Through long-term use, the patch can protect a woman against ovarian cancer, endometrial cancer and ovarian cysts, Planned Parenthood reports.
Possible Side Effects
Like other types of birth control, the patch has side effects. The American Pregnancy Association lists bloating, weight gain, breast tenderness, headaches, nausea and vomiting as side effects. Irregular vaginal bleeding, which includes bleeding in between periods, can also occur when the body is adjusting to the hormone levels. Because the birth control patch is attached to the skin, skin irritation is also possible.
Warnings
The American Pregnancy Association warns that the birth control patch should not be trimmed or attached to the skin with another form of adhesive. Once placed, the patch should not be moved until the end of three weeks. The birth control patch also does not protect the user against sexually transmitted diseases (STDs).
