Most women can become pregnant from the time they are in their early teens until they are in their late 40s. Birth control (or contraception) helps a woman plan her pregnancies.
How Birth Control Works
A woman has two ovaries, one on each side of the uterus. Each month, one of the ovaries releases an egg into a fallopian tube. This release of an egg is called ovulation.
A woman can get pregnant if she has sex around the time of ovulation.
If a sperm meets an egg in the fallopian tube, fertilization (the joining of egg and sperm) can occur.
Birth control methods work in a number of ways. They may:
Block the sperm from reaching the egg
Keep eggs from being released each month
Change the lining of the uterus
Thicken the mucus in the cervix so sperm cannot easily pass through it
There are many methods of birth control. The greatest benefit of effective birth control is that it allows a woman to plan her family.
With hormonal birth control, a woman takes hormones like those her body makes naturally. These hormones prevent ovulation.
Birth control pill. The most used method of hormonal birth control is the birth control pill (oral contraceptive). The pill is safe and highly effective when taken each day.
Birth control patch. The birth control patch. is described here.
With implants, match-size, soft plastic tubes are placed just under the skin of the upper arm. Implants provide birth control for up to five years. The hormones in implants may make your periods irregular.
One injection of hormonal birth control provides birth control for three months. This means a woman needs only four injections each year. During the time that the injection is effective, you don’t have to do anything else to prevent pregnancy. You may have irregular periods.
If a woman has sex without any type of birth control, she may be able to use a type of backup birth control called emergency contraception. In this method, high doses of certain birth control pills are taken within 72 hours (three days) of sex without birth control. Emergency contraception greatly reduces the chance that a woman will become pregnant. It is not as effective as using birth control on a regular basis, though.
The IUD is a small, plastic device that contains copper or hormones. It is inserted and left in the uterus.
The hormonal IUD must be replaced every year. The copper IUD can remain in place for up to 10 years.
The IUD does not protect against STDs.
The IUD is best suited for women who have given birth to at least one child.
Barrier methods include the diaphragm, cervical cap, condom (male and female), sponge and spermicides.
The diaphragm, cervical cap, sponge, and male and female condom act as physical barriers. They keep the sperm from getting to the egg.
These methods are used with spermicides to further lower the risk of pregnancy.
The withdrawal method prevents pregnancy by not allowing sperm to be released in the woman’s vagina. This requires the man to take his penis out of the woman before he ejaculates. Drawbacks are that sperm can be present in the fluid produced by the penis before ejaculation.
Natural Family Planning
Natural family planning also is called periodic abstinence or the rhythm method. This method can work only if you do not have sex during those times in your menstrual cycle when your chances of becoming pregnant are greatest.
Sterilization for women and men works by permanently blocking the pathways of egg and sperm. This is done by surgery.
For women, both fallopian tubes are closed by tying, banding, clipping, or cutting them or by sealing them with electric current. This is called tubal ligation.
For men, vasectomy involves clamping, cutting and sealing the tubes that carry sperm to the penis.
Sterilization is meant to be a permanent form of birth control. If there is a chance you may want to have a baby later, you should not choose this method.
Choosing a Method
At any given time, a couple may find one method of birth control suits their needs better than others.
All methods have a chance of failure.
Most birth control failures result from not using birth control correctly each time.
No matter which method of birth control you choose, be sure that you know how it works, how to use it, and what side effects may occur. Even with methods that do not need a prescription, you need to learn how to use the method. A doctor, nurse or family planning counselor can teach you.
The more you know about birth control and your own needs, the easier it will be to choose a method that’s right for you.
This excerpt from ACOG’s Patient Education Pamphlet is provided for your information. It is not medical advice and should not be relied upon as a substitute for visiting your doctor. If you need medical care, have any questions, or wish to receive the full text of this Patient Education Pamphlet, please contact your obstetrician-gynecologist Check out our