The birth control pill has been the most popular, long-standing contraceptive choice among women, but a more permanent route is close behind. A nationwide survey conducted by the Centers for Disease Control and Prevention (CDC) found the unexpected contraceptive approach of female sterilization is almost as frequently used as birth control pills.

Opting for surgery seems extreme “until you start to peel back the layers and intricacies around forming a family,” Dr. Vanessa Cullins, vice president of external medical affairs at Planned Parenthood Federation of America, who was not involved in the study, told Time. “Consider the fact that the majority of women in this country have had the number of children they want to have by [their] mid-20s to 30, or so — and they still have the capacity to get pregnant until they are 50 years old.”

The dangers of becoming pregnant continue to increase significantly after the age of 30, when many women have already given birth to the amount of kids they want. There are roughly 20 years between that time and when she physically can’t anymore because of menopause. According to Cullins, the majority of women who ask about sterilization don’t want to deal with other contraceptive methods, especially those that require maintenance.

Nearly 62 percent of women in the U.S. between the ages of 15 and 44 use some form of contraceptive. The survey found that between 2011 and 2013, 16 percent of women were using birth control pills while 15.5 percent were choosing female fertilization. Male condoms came in third place with 9.4 percent of couples using them during sex, and long-acting reversible contraceptives such as intrauterine devices (IUD) came in last at 7.2 percent. Experts are expecting IUDs to become more popular as the industry makes them more affordable, although younger sexually active women between the ages of 15 and 24 were less likely to use them.

Female fertilization appeals more to middle-aged women because of its reassuring statistics. Less than one out of every 100 women who are sterilized become pregnant, meaning it provides a lifetime of reliability. It’s commonly known as a woman getting her "tubes tied" because her fallopian tubes are literally cut or blocked. The tubes lead to the woman’s ovaries, and into the uterus or womb. If the sperm can’t cross the tubes, it’s not possible for them to fertilize the egg and conceive a pregnancy.

Source: Daniels K, Daugherty J, Jones J. Current Contraceptive Status Among Women Aged 15–44: United States, 2011–2013. NCHS Data Briefs. 2014.