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Understanding Birth Control

More Methods of Birth Control
©2006 Publications International, Ltd.                                      Vasectomy is a method of male sterilization in                              which each vas deferens is cut and tied off.
©2006 Publications International, Ltd. Vasectomy is a method of male sterilization in which each vas deferens is cut and tied off.

We continue our treatment of birth-control methods with the intrauterine device (IUD) and others.

Intrauterine Device (IUD)

The intrauterine device (IUD) is a small plastic device inserted into the woman's uterus by a physician. The IUD has a string attached to it that hangs into the cervix, so that the woman can check to be sure that the IUD is still in place. Most researchers believe that the IUD prevents pregnancy by causing changes in the uterine lining that disrupt the normal environment of an egg. For the woman who can use an IUD, the advantages are great, because she does not have to worry about contraception each day. The effectiveness rate is high, with less than a 1 percent chance of pregnancy.

However, there are several disadvantages to the use of an IUD. Severe menstrual cramps and increased menstrual bleeding may follow the insertion of an IUD. Sometimes these side effects lessen after a month or two. In other cases, severe cramps and prolonged bleeding continue, and the physician may advise removal of the IUD. The IUD is also thought to increase the probability of pelvic infections within the first few months following insertion.


A woman may be sterilized by an operation that blocks the fallopian tubes (the structures through which eggs travel from the ovaries to the uterus). A man may be sterilized by a procedure called a vasectomy, in which each vas deferens (one of the two ducts through which the sperm travel from the testes to the urethra) is cut. These procedures may be reversed but only by complicated surgery, which is not always successful. Therefore, physicians recommend sterilization only when a couple has decided, without reservation, that they desire no further pregnancies.

Oral Contraceptives

Oral contraceptives, or birth control pills, are one of the most effective reversible methods of contraception. A woman taking the pill properly has less than a 1 percent chance of getting pregnant.

The pill -- which is available by prescription only -- uses synthetic female hormones (estrogen and progestin) to override the natural hormonal regulation that results in the release of an egg. The pill signals the pituitary gland, which directs hormonal activity in the body, not to release the hormones that would normally stimulate the ovary to release an egg.

Each day the woman takes one pill, at about the same time of day, removing it from a container that has the required number of pills for one cycle (usually 21). One to three days after she takes the last pill for that cycle, her menstrual period begins. Menstrual periods may be lighter in flow, and cramps may be reduced or absent.

If she forgets to take one pill or more, menstrual bleeding may begin. In that case, she should continue taking the pills daily, but she should also use another contraceptive method, such as a condom, until after her next regular period.

Birth control pills are not recommended for women with a history of high blood pressure, blood-clotting problems, hepatitis, or cancer of the uterus or breast. A woman over age 35 who smokes is advised to stop smoking if she wants to take the pill. Birth control pills should not be taken by a woman who suspects she may be pregnant. In addition, women with diabetes, epilepsy, heart disease, or thyroid disease may be advised not to take birth control pills, depending on the nature and severity of the disease.

It is important for a woman taking birth control pills to report to her doctor if any of the following symptoms occur: blurred vision; severe chest pain; sudden shortness of breath; abdominal pain; unusual bleeding or bruising; breakthrough vaginal bleeding (spotting); changes in menstrual flow; pain in the calves; depression; difficult or painful urination; enlarged or tender breasts; hearing changes; increase or decrease in hair growth; migraine headaches; numbness or tingling; rash; skin color changes; swelling of the feet, ankles, or lower legs; vaginal itching; weight changes; or yellowing of the eyes or skin.

Hormonal Implants

The newest form of contraception is the hormonal implant. With this method, six small plastic rods containing the synthetic female hormone progestin are inserted with a needle under the skin of the upper arm or forearm. The hormone is gradually and slowly released from the plastic rods, thus preventing ovulation. This method is effective for about five years from the time the implants are inserted. The major advantage of this method is that the woman does not need to remember to take birth control pills or use a spermicidal agent or diaphragm before each sexual act. Disadvantages include the high cost of the implants, possible infection at the site of insertion, irregular menstruation, and the necessity for surgical incisions on the arm when the implants need to be removed. Hormonal implants are about as effective as oral contraceptives.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.