Sex may be spontaneous but choosing the right birth control takes planning. Do you want to take daily pills or use an easier "set-and-forget" method? Do you feel hesitant about hormonal contraception? Who should take responsibility: the male or female partner? Are you ready for sterilization or looking for long-term but reversible solutions?
There's no single best type of birth control. "What might be great for you when you're 17 might not really be ideal for you when you're 26 or 36," says Megan Kavanaugh, a principal research scientist at the Guttmacher Institute. "An average woman uses about four methods over her reproductive lifetime because she switches to what's most appropriate for her different stages of life."
Kavanaugh's latest study, published in the January 2018 issue of the journal Contraception, looked at contraceptive methods among nearly 24,000 U.S. females. Participants ages 15 to 44 disclosed the primary method used by themselves or partners.
Throughout the 2008 to 2014 study period, the pill, female sterilization and male condoms remained the three most popular methods. In 2014, intrauterine devices edged out vasectomy as the fourth most-common type.
As women move into their 30s, some choose to shift to shorter-lasting methods. However, Kavanaugh emphasizes, because IUDs and implants can be removed at any time, they also work for shorter-term contraception.
Female sterilization rates declined from 27 percent to 22 percent by the study's end. Among women in the 40 to 44 age range, 46 percent chose sterilization. Only 16 percent reported male sterilization as a couple's primary method.
By about 48 to 50, a woman's risk of becoming pregnant is very low, says Dr. John Bertrand, an OB-GYN physician with Walnut Hill Obstetrics and Gynecology Associates in Dallas. "But with someone who's regular and cyclic, we'd still recommend protection," says Bertrand, who is a clinical professor at University of Texas Southwestern Medical School. At age 52 or so, he says, women can safely go without.
One potential downside to hormonal birth control is a slightly higher risk of breast cancer, according to another recent study. Findings suggest that today's birth control pills, patches, rings, implants and hormone-releasing IUDs continue to pose a risk similar to that of older versions of the pill.
In the study, 1.8 million Danish women were followed for about a decade through 2012. Overall, results showed a small but significant increase in breast cancer risk for women who had ever used hormonal contraceptives. The longer women used these methods, or the older women were, the more elevated their risk was, according to the study published last month in the New England Journal of Medicine
However, of women under 35 who had used hormonal birth control, only two women per 100,000 would develop breast cancer, according to an accompanying NEJM editorial. Previous research shows oral contraceptives actually reduce the risk of ovarian and endometrial cancer, the editorial author pointed out.
The benefits of current contraceptive methods far outweigh the risks, Bertrand says. Pregnancy itself involves greater health risks, he notes, especially for older mothers.
Here's a brief rundown of some popular birth control methods:
Pills: All birth control pills rely on hormones to prevent ovulation. Combination pills such as Ortho Tri-Cyclen, Loestrin and Yaz contain estrogen and progestin. Mini-pills such as Camila and Ortho Micronor contain progestin alone. Generic brands are also available.
PRO: If used correctly, the pill is highly effective. It also can help regulate menstrual periods, reduce heavy bleeding and cramping, and treat acne.
CON: Because the pill doesn't protect men or women from sexually transmitted infections, condom use during sex is also recommended.
Condoms: Male condoms are the No. 1 barrier method of birth control. Adding a spermicide, which works by killing sperm, makes condoms even more effective.
PRO: Condoms can also be used during oral, vaginal or anal sex to prevent the spread of STDs.
CON: If they're not used correctly or consistently, pregnancy is possible.
IUDs: The small, flexible, highly effective device is inserted into the uterus to prevent pregnancy. Insertion can be done in a clinic or doctor's office. Hormonal IUDs release small daily doses of synthetic progestin, over three, five or 10 years. Copper IUDs work without hormones.
PRO: IUDs are extremely long-lasting and quickly reversible. Women should understand that today's IUDs are much improved, Bertrand says: "The devices we have now are extremely safe and have a great track record."
CON: Many women experience pain during insertion as well as cramping, backaches and bleeding several days or longer after insertion. Rarely, serious side effects such as infections or perforation of the uterus can occur.
Implants: Birth control implants offer another long-lasting, set-and-forget reversible alternative. The matchstick-sized, progestin-only rod is inserted into a woman's upper arm. The implant, whose brand name is Nexplanon, lasts for three years.
PRO: Insertion is less invasive and generally less painful than for IUDs. Implants are "extremely effective" with a failure rate of only 0.05 percent, according to the Association of Reproductive Health Professionals.
CON: Bleeding irregularities and missed periods are common side effects. Infrequent side effects include weight gain, acne and mood swings.
Patches: The transdermal contraceptive patch is another hormone-release method. Women simply place the patch, which lasts for three weeks, on their upper arm, abdomen or back. After a weeklong break, they apply a fresh patch.
PRO: Patches are painless, affordable and easy to use.
CON: You must remember and adhere to the schedule.
Tubal Ligation: Tubal ligation, or having one's tubes tied, is a major surgical procedure. With fallopian tubes surgically shut, sperm can no longer reach the egg. Another less-invasive permanent procedure, called Essure, uses small inserts to block the fallopian tubes.
PRO: Tubal ligation lets women who aren't interested in having more (or any) children enjoy sex with less worry.
CON: There's a small chance an ectopic or "tubal" pregnancy can occur after a tubal ligation.
Vasectomy: A simple surgical procedure, vasectomy works by either cutting or blocking the sperm-carrying tubes in the testicles. Vasectomy is highly effective and recovery is relatively easy.
PRO: Among couples ready to be done with childbearing, some men view vasectomy as a chance to do "their part" in contraception, Bertrand says.
CON: Not all men can deal with the idea of vasectomy. "There are some who are just petrified of it," he says.
Natural Methods: Some people prefer birth control without medications or devices. Methods include withdrawal, abstinence and natural family planning. Fertility awareness involves either avoiding sex during a woman's fertile days in each monthly cycle, or using condoms during that time.
PROS: Abstinence is the most effective way to prevent pregnancy and sexually transmitted disease.
CONS: For many people, abstinence is not realistic or desirable. Although the use of withdrawal has slightly increased in the U.S., it's not highly effective.
Other birth control methods include vaginal rings, hormonal injections, contraceptive sponges, female condoms, diaphragms and cervical caps. Discuss effectiveness and side effects with your gynecologist or other health care provider when deciding on the right method for you.