Birth Control Pill & Pregnancy Risks

For many women, the birth control pill is their preferred method of contraception due to its high success rate in pregnancy prevention and because of the convenience it provides since it does not interfere with sexual intercourse. In some cases, women who do not need to use birth control will take it to reduce menstrual cramps, lighten periods or protect against acne.

Function

• Birth control pills are prescription medications designed to prevent pregnancy by the use of synthetic hormones and, if taken as directed, can provide 99 percent effectiveness in pregnancy prevention. Since the effectiveness of oral contraceptives is dependent upon how closely the user follows a regimented dosing schedule, the average effectiveness of oral contraceptives is between 93 percent and 97 percent due to missed or delayed doses.

Types

• There are three ways in which pregnancy is prevented by the birth control pill: by preventing ovulation each month; by producing less cervical mucus, making it more difficult for sperm to enter the uterus; or by thinning the endometrial lining of the uterus, making it more difficult for a fertilized egg to implant. There also is an emergency birth control pill known as Plan B. This type of contraceptive works by providing an intense, short dose of synthetic hormones in order to interrupt the hormone patterns required for a pregnancy to occur. It is generally is effective if taken within five days after sexual intercourse.

Time Frame

• Pregnancy is more common to occur during the first few months of starting the birth control pill and if doses of the pill are missed. If one pill is missed during a cycle, it should be taken as soon as possible, even if it means taking two pills in the same day. If two pills are missed in a row within the first two weeks of a cycle, they should be taken as soon as possible, followed by two pills the next day. If two pills are missed in a row in the third week of a cycle, continue to take one pill regularly until Sunday and then begin a new pack on Sunday. In the case of missing three pills in a row, take one pill as usual until Sunday, then a new package of pills should be started.

Prevention/Solution

• The most effective way to prevent pregnancy while taking the pill is to follow dosing instructions carefully. The pill should be taken at the same time each day during the month to ensure the greatest defense against conception. When the pill is started within six days after a period has begun it is effective immediately, but if it is started at any time after that it is effective after one month. Condoms can be used in addition to the birth control pill in order to further protect against conception and sexually transmitted diseases.

Warning

• Women who use oral contraceptives are at an increased risk of stroke and heart attack. Contact a doctor if severe abdominal pain, chest pain or shortness of breath, blurred vision, headaches, or leg or arm pain or numbness occur at any time while taking the pill. In addition, certain prescription medications can interfere with the effectiveness of the birth control pill, therefore, women should use a back up method of birth control when taking antibiotics and other medications specified by a health care professional.