Birth Control

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Introduction

Birth Control or Contraception, deliberate prevention of pregnancy using any of several methods. Birth control prevents a female sex cell (egg) from being fertilized by a male sex cell (sperm) and implanting in the uterus. In the United States, about 64 percent of women aged 15 to 44 years practice some form of birth control. When no birth control is used, about 85 percent of sexually active couples experience a pregnancy within one year.

There are a variety of birth control methods to choose from, although most options are for women. Selecting a method is a personal decision that involves consideration of many factors, including convenience, reliability, side effects, and reversibility (whether the method is temporary or permanent). For instance, some people may prefer a birth control option that provides continuous protection against pregnancy, while others may prefer a method that only prevents pregnancy during a single act of sexual intercourse. Some people might have past illnesses or medical conditions that prevent them from using certain types of birth control methods. Some women may find that certain birth control methods cause uncomfortable side effects, such as irregular menstrual bleeding, weight gain, or mood changes. A person with multiple sexual partners may prefer a birth control method that also offers protection from sexually transmitted infections (STIs). Another important consideration is whether a person ever plans to have children. Most birth control methods are reversible—they do not affect a person’s ability to reproduce once the method is halted. But surgical birth control methods cannot, in most cases, be reversed; once a man or woman undergoes the surgery, he or she can no longer reproduce.

In addition to choosing the type of method to prevent pregnancy, men and women are faced with a number of other reproductive choices. Experts use the broader term family planning for the process of making decisions about when to have children and how many children to have, as well as strategies for achieving these goals.

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Effectiveness

No birth control method, other than abstinence from sex, is 100 percent effective in preventing pregnancy. Some methods are more effective than others, and scientists use two types of pregnancy rates when describing effectiveness. Method effectiveness, or perfect use, is the percentage of pregnancies that occur when a particular method is used correctly and consistently with each act of sexual intercourse. User effectiveness, or typical use, is the percentage of pregnancies that result from average use of the method, which accounts for improper or inconsistent use. This article provides typical use statistics in its overview of birth control methods.

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III

Types of Birth Control

Birth control methods work in different ways to prevent pregnancy. Some methods prevent sperm from meeting eggs. Others affect a woman’s hormones, altering her reproductive cycle. Other birth control methods involve behaviors that alter sexual activity in ways that lessen the chance for pregnancy.

A

Barrier Methods

Barrier methods physically block sperm from entering the uterus to unite with an egg. Barrier methods must be used with each act of sexual intercourse. While they are easy to use, some people feel barrier methods are inconvenient because they interfere with sexual spontaneity. Barrier methods include male and female condoms, the diaphragm, the cervical cap, and spermicides.

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