Birth control is key to anyone who chooses to have sex but wants to avoid pregnancy. A couple under age 30 who has unprotected intercourse has about an 85 percent chance of conceiving a pregnancy each year. Nearly 50% of pregnancies in the U.S. today are still unplanned. It should be obvious that anyone who chooses to have sexual intercourse and does not want to contribute to a pregnancy needs to take intentional measures to avoid pregnancy. There are lots of good means of contraception, but unfortunately no means of avoiding pregnancy is 100% effective except abstaining from sexual intercourse. Recently many experts recommend using one of the highly effective set-and-forget types of contraception for sexually active young women. These methods include IUDs, the implantable progestin method Nexplanon, and depo-Provera. In discussions below of the effectiveness of the various methods of contraception the quoted statistics are from the Contraceptive Technology Table available on-line.
Methods of birth control can initially be separated into permanent means of birth control and temporary means. This site will mention the permanent means of contraception only briefly. The permanent options are vasectomy for males and tubal ligation for females. Both of these methods work by preventing the egg or sperm from passing through the tube to the partner’s egg or sperm.
Temporary contraception falls into three basic types. These are barrier methods of contraception, hormonal contraception and intrauterine devices.
Barrier Contraception: Barrier means of contraception work by putting a temporary barrier between the sperm and the cervix. In general barrier methods have the advantage of varying degrees of protection from sexually transmitted diseases, don’t require a physician prescription for most methods, and are readily accessible to most people. Their biggest disadvantages are that they require use with each episode of sex, and that even used perfectly have a higher failure rate resulting in more pregnancies than most other methods of contraception.
Condoms: Condoms are the most commonly used means of barrier contraception. Condoms are a latex rubber sheeth that fits over the penis to collect semen that is ejaculated and prevent it from getting into the vagina. Condoms also function to reduce the transmission of many sexually transmitted diseases, including HIV, chlamydia, and gonorrhea. Condoms are less effective at preventing transmission of HPV, herpes simplex and syphilis but do reduce transmission to some degree. Condoms have the major drawback of requiring active use with each episode of intercourse, of falling off or breaking, and of need for proper use. With optimal use the theoretic pregnancy rate for condom use is 2% per year. In actual practice the pregnancy rate of condom use is about 15% per year. Most single sexually active couples should use condoms with every sex act to give some protection from STDs even if they use a hormonal means of contraception.
Female Condoms: These are a latex or vinyl barrier that is placed in the vagina and over the outside of the female genitalia. They also function to prevent semen and sperm from accessing the vagina. They have the same need for every time use as male condoms, and have the same benefit of STD transmission reduction. Because of higher cost and less user satisfaction they are much less frequently used than male condoms. They also have higher failure rates with a 5% failure rate with prefect use and a 21% failure rate with typical use.
Cervical caps: The cervical cap is a small cap that can be fitted to the cervix by a physician and can be placed over the cervix by women to prevent access of sperm to the cervical canal. They are rarely used and are seldom a viable option for young single women. They need to be used with a spermicidal agent.
Diaphram: A diaphragm is a latex barrier that is placed in the vagina to hold a contraceptive gel in place over the opening to the cervix so that sperm cannot successfully get to the egg. Diaphrams need to be fitted to the woman by a health care provider, and used with each episode of intercourse. They need to be left in place for at least 4 hours after intercourse. More details are available online if desired. About 6% of women become pregnant in the first year of diaphragm use with perfect use, and about 16% become pregnant in actual use.
Contraceptive Sponge: This is a disposable spermicide containing sponge that can be placed in the vagina prior to intercourse. Like the diaphragm it needs to be used with each episode of sex and left in place for __ hours after intercourse. Pregnancy rates with the sponge use are higher in women who have had children. In women with no prior children about 9% of women become pregnant with perfect use and 16% with actual use. Rates are much higher in women who have had children.
Spermicidal Agents: These are chemicals that can be put into the vagina to kill sperm. They are available as gels, creams foams and tablets. They are best used as an additional measure along with one of the other barrier methods mentioned above. Alone they are not effective enough to be used as a primary means of contraception, with actual use pregnancy rates are about 29% in the first year of use. Nonoxynol-9 is the common widespread spermicidal agent used. A small percentage of people develop an allergy to this agent and cannot use spermicidals.
Hormonal contraception: They are of two major types, combination estrogen and progestin contraception, and progestin only contraception.
Estrogen and Progestin Contraception: Combination estrogen and progestin hormonal contraception uses a mixture of low dose estrogen and progestin to prevent ovulation and more importantly to prevent the normal development and maturation of the lining of the uterus. Preventing ovulation prevents pregnancy and in the cases where ovulation occurs the hormones both make the cervix inhospitable to sperm preventing sperm form successfully accessing the egg and they interfere with development ant maturation of the endometrial lining preventing successful implantation of a fertilized egg even if ovulation occurs and a sperm gains access to the egg and fertilization of the egg occurs. Progestin only contraception works primarily by changing the cervical mucus so that sperm do not make it through successfully. They also prevent normal maturation of the endometrial lining and frequently prevent ovulation.
Following are the various types of hormonal contraception:
Combination Birth Control Pills: These pills have been used for over 40 years, and now are all very low in estrogen dose. There are many brands of pills, but lots of good generic options are available. The pills are designed to be used cyclically, so that a woman takes a hormone containing pill every day for 21 days, and takes a timing pill without hormones for 7 days. During the 7 days off hormones there is usually a withdrawal bleed that mimics the normal menses. On the 29th day a new package of pills is started. Sometimes physicians and patients choose to use the pills continuously. Only some brands of pills are able to be used continuously, so DON’T TRY THIS ON YOUR OWN. In continuous use a fixed dose combination birth control pill is taken for the 21 days, and instead of taking the 7 timing pills and having a withdrawal bleed, the woman starts the next package of pills on the 22nd day and discards the 7 timing pills. Used in this way the woman avoids withdrawal bleeding, and some women have few if any days of bleeding. Other women have irregular and annoying bleeding and dislike continuous use pills. Both methods have similar failure rates. About 2-8% of women on birth control pills will get pregnant each yea in actual use, and perfect use failure rate is about 0.3%. Some brands of pills are marketed for less frequent withdrawal bleeding, like Seasonalle and _____. Forgetting to take the pills daily is the most common cause of failure of birth control pills.
Birth control patches: Currently only Ortho-Evra is available as a contraceptive patch. It is placed on the skin of the torso for 3 weeks, and removed for a week. The week of not wearing the patch is like the week of timing pills mentioned above, and allows for a withdrawal bleed. Rates of pregnancy are similar to with the birth control pill. The cost of the Ortho Evra patch is higher than generic birth control pills.
Nuvaring: The Nuvaring is a hormone eluting ring that is placed into the vagina for 3 weeks, and removed for a week. It works in the same way as birth control pills and the OrthoEvra patch, and has similar failure rates. Some women prefer the convenience of the once monthly ring. Other women dislike having to put it into the vagina and remove it. The cost of the Nuvaring is higher than generic birth control pills.
Progestin only pills: These are also called the mini-pill, and are used continuously daily. They are less popular that combination birth control pills primarily because they have a slightly higher higher failure rate (more chance of pregnancy) and users often have irregular bleeding. About 8% of women become pregnant in the first year of progestin only pill use, with a theoretical failure rate with perfect us of 0.3%. They have the advantage of not containing estrogen, and so are often used by women during breast feeding. Estrogen containing pills may slightly reduce milk supply in the first couple of months of establishing milk supply.
Implanted Progestin Devices: At this time the only such device is Nexplanon. It is implanted under the skin of the upper inner arm and provides excellent contraception for up to 4 years. Benefits are that is requires no active role of daily, weekly, or monthly of the user. Once it’s in place contraception is effective. Drawbacks can be irregular bleeding in some women. Failure rates with Implanon are extremely low at 0.05% annually.
Injected Progestin: Brand name Depo-Provera, now available as generic depo-progesterone, this is a popular injected progestin that is injected every 3 months. It provides very effective contraception, with pregnancy rates less about 3% in the first year of actual use, and of 0.3% with perfect use. Advantages are lack of estrogen use. Disadvantages are that some women have irregular bleeding, weight gain and fluid retention. Moodiness is also sometimes reported.
Post-coital contraception: An FDA approved hormonal method to prevent pregnancy after unprotected intercourse or after barrier failure (broken condom, etc) is Plan B. It is a hormone that can be taken up to 72 hours after intercourse and it reduces the chance of pregnancy by up to __%. As its name implies it is not a great choice for primary contraception, rather as a backup option if primary measures of contraception are not used or failure is suspected. Physicians may also prescribe other hormone combinations for post coital contraception that are also reasonable effective.
Intrauterine devices: IUDs as these are called are small plastic devices that combined with copper or progestin hormone can be implanted in the uterus and prevent pregnancy. They have the advantage being effective, are hands off once put in place, and are usually well tolerated by women. Only two IUDs are marketed in the US ParaGuard is a copper containing device, is effective for up to 10 years, and contains no hormones. Mirina is a progestin containing device that gives up to 5 years of contraception. Mirina often leads to light or no menses in the user which some women prefer. In a small percentage of women Mirina can lead to irregular bleeding. Any IUD puts women at higher risk of serious pelvic infections called pelvic inflammatory disease (PID), especially if chlamydia or gonorrhea is contacted, and so are not good options for women with multiple partners or who are felt to be at risk for STDs. Infertility can be a complication of PID in some women. IN general IUDs are easier to place and are better tolerated in women who have had children, but they, are also used in women prior to childbirth.
Abortion is a topic in itself and will not be discussed in this section.
The authoritative text on contraception is Contraceptive Technology and is published annually. The most comprehensive and accurate free online sex education birth control resource is probably Contraceptivetechnology.org