American Medical Association Family Medical Guide - American Medical Association [244]
The insertion takes only a few minutes, but it sometimes causes brief cramping pain. Once inserted, the IUD protects against pregnancy. An IUD can be accidentally expelled at any time, so you should check frequently to make sure it is still in place. A good time to check is toward the end of your period (because both menstrual cramps and tampon insertion and removal can increase the risk of expulsion). You can check for the IUD by inserting your finger inside your vagina; if you can feel the string, the IUD is in place. If you feel the hard plastic of the IUD, it is being expelled. See your doctor so he or she can remove the IUD and replace it with a new one.
The most common problem with copper IUDs is the slight risk of increased menstrual bleeding and intensified menstrual pain, although most users do not experience these problems. The copper IUD prevents pregnancy for 10 to 12 years. But the copper IUD may not be the best contraceptive method for you if you already have long and painful periods. An IUD that releases timed doses of progestin (a form of the female hormone progesterone) causes less menstrual bleeding—but it prevents pregnancy for only 5 years.
How an IUD prevents pregnancy
When correctly positioned in the uterus, an IUD prevents an egg from being fertilized by preventing sperm from reaching the fallopian tubes. Hormone-releasing IUDs thicken the mucus produced by the cervix, blocking sperm from the uterus, and also may make the uterine lining thinner and less favorable for implantation of a fertilized egg. Both types of IUD have plastic strings attached to the lower end to make removal easier.
If you are not in a mutually monogamous sexual relationship and you have an IUD, you are at an increased risk of developing pelvic inflammatory disease (PID; see page 871) from a sexually transmitted disease (STD; see page 477). Untreated, PID can lead to ectopic pregnancy (see page 523) and infertility. To protect against pelvic infection, use a latex condom each time you have intercourse.
Hormone Injections
Injection of progestin (a form of the female hormone progesterone) every 3 months provides highly effective birth control. The hormone blocks ovulation and increases the thickness of the mucus secreted by the cervix, making penetration of sperm more difficult. An alternative injectable contraceptive—which is 99 percent effective—combines progesterone and estrogen to prevent ovulation but lasts only 28 days. Both injections are given in a woman’s arm or buttocks during the first 5 days of her period.
Hormone injections lessen menstrual cramping and protect against cancers of the ovary and uterus. Common side effects include irregular bleeding, lighter periods (which may eventually stop altogether), longer and heavier periods, bleeding between periods (breakthrough bleeding or spotting), sore breasts, or weight gain. Women with unexplained vaginal bleeding, a history of blood clots, liver disease, or breast cancer should not use hormone injections for birth control. Regular ovulation and fertility usually resume about 6 to 9 months after the last injection of progesterone, somewhat sooner if the combined hormone injection is used.
Contraceptive Patch
The contraceptive patch prevents pregnancy by releasing the hormones estrogen and progestin (a form of the female hormone progesterone) directly into the skin. The hormones prevent ovulation and cause the mucus released by the cervix to thicken, inhibiting penetration by sperm. A patch is applied to the skin (on the upper, outer arm; the back; the lower abdomen; or the buttocks) every week for 3 weeks in a row. No patch is worn the fourth week, triggering menstruation. The cycle is repeated as long as birth control is desired. The patch stays adhered to the skin even during showering, bathing, and swimming.
The side effects of the contraceptive patch are similar to those of the birth-control