Many women choose to use birth control to prevent an unwanted pregnancy. Some forms, like the birth control pill and injection, contain synthetic forms of the hormones estrogen and progesterone. Other types of birth control, like the copper intrauterine device, do not have hormones, but the ingredients help prevent pregnancy. However, while the success rate for these forms of birth control are high, there is still a possibility that you can get pregnant, especially if you do not take the birth control on time or correctly.
Birth Control Pill
Three types of birth control pills are available to women: the combination pill, the progestin-only pill and the extended cycle pill. The progestin-only pill contains a synthetic form of progesterone, progestin, while the extended cycle and combination pills have both estrogen and progestin. The extended cycle pill does not include a week of nonhormone pills every month, so menstruation is also prevented.
According to the Mayo Clinic, when a birth control pill is taken correctly, it is 92 percent effective. Correct use of a birth control pill is taking it daily at the same time. However, if you miss a dose or take your pill much later than normal, then you have an increased risk of becoming pregnant. In addition, if you vomit within a half hour of taking your birth control pill, the pill is not fully absorbed and you can become pregnant. To prevent an unwanted pregnancy during those times, use a backup method of birth control.
Copper Intrauterine Device
One long-term option of birth control is an intrauterine device, or IUD, which is inserted in your uterus. Intrauterine devices can be copper-based or hormone-based, and can stay inserted for up to 10 years. The copper intrauterine device, like the ParaGard IUD, acts like a spermicide; however, according to YourContraception.com, copper intrauterine devices do not prevent ovulation like hormone-based birth control methods do. Thus, even though the copper intrauterine device is 90 percent effective, it is still possible for women using copper IUDs to become pregnant while the IUD is still inserted. Becoming pregnant while the intrauterine device is inserted puts you at an increased health risk: if the IUD is not removed, you can suffer from miscarriage or ectopic pregnancy.
A hormone-based, long-term birth control option is Depo-Provera, a birth control injection. According to the American Pregnancy Association, Depo-Provera contains depo-medroxyprogesterone acetate (DMPA), a synthetic form of progesterone that prevents ovulation. Depo-Provera is given every 11 to 13 weeks and is injected in either your upper arm or buttocks. The failure rate of Depo-Provera is under 1 percent; however, you are at an increased risk of pregnancy if you do not follow up for your next shot in the following 11 to 13 weeks.