The birth control patch is a thin, beige, 1¾-inch (4½-centimeter) square patch that sticks to the skin. It releases hormones through the skin into the bloodstream to prevent pregnancy.
How Does the Patch Work?
The combination of the hormones progesterone and estrogen in the patch prevents ovulation (the release of an egg from the ovaries during a girl's monthly cycle). If an egg isn't released, a woman can't get pregnant because there's nothing for the male's sperm to fertilize.
The hormones in the patch also thicken the cervical mucus (the mucus produced by cells in the cervix). The cervix is the part of the uterus that sits within the vagina and acts as the opening to the uterus. The thickening of cervical mucus makes it difficult for sperm to enter the uterus and reach any eggs that may have been released. The hormones in the patch can also sometimes affect the lining of the uterus so that if the egg is fertilized it will have a hard time attaching to the wall of the uterus.
Like other birth control methods that use hormones, such as the birth control pill or birth control ring, the birth control patch is used based on a young woman's monthly menstrual cycle. She applies the patch on the first day of her menstrual cycle or the first Sunday after her menstrual cycle begins. She will change the patch on her skin once a week for 3 weeks in a row. (The patch should be applied to one of these four areas: the abdomen, buttocks, upper outer arm, or upper torso — except for the breasts.) On the fourth week, no patch is worn, and the menstrual period should start during this time. It's important to use an additional form of contraception during the first 7 days on the patch to prevent pregnancy.
A new patch should be applied on the same day every week to make sure that it keeps working effectively. For example, if the first patch is applied on a Monday, patches should always be applied on a Monday. When it's time to change the patch, the old one should be pulled off first, before applying a new patch. The new patch should be placed on a different area from the old patch (but still on one of the four recommended areas) to avoid skin irritation. And any skin that is red, irritated, or cut should be avoided.
If a patch becomes loose and falls off or if a woman forgets to apply a new patch on the right day, she should consult the labeling information or a doctor about what to do. A backup method of birth control may be necessary for a while, such as condoms, or she might need to stop having sex for a while to protect against pregnancy. Also, if a young woman stops using the patch for any reason, she will need to begin using another method of birth control, usually 24 hours after removing the last patch.
It's OK to participate in regular activities like swimming and exercise while wearing the patch. It can also get wet in the shower or in the bath. However, the patch should not be moved or removed until the week is over (pulling the patch off to reposition or move it may cause it to lose some of its stickiness and it might fall off easily). If the patch does not stick well, a replacement patch should be applied. A girl wearing a patch shouldn't try to change its size by trimming it or try to attach it with tape.
The patch should not be applied over makeup, creams, lotions, powder, or other skin products as these may prevent it from sticking well. (Skin products may also affect how hormones are absorbed by the skin.)
A removed patch should be folded in half with the sticky sides facing each other (to prevent the chemicals from getting into other items in the trash and going to the soil) and thrown away (not flushed down the toilet).