More women are turning to intrauterine devices for birth control. Over the past five years, Planned Parenthood has seen a 91 percent increase in demand for the devices, also called IUDs.

An IUD is a long-lasting, reversible contraceptive device that can protect women from pregnancy for up to 10 years, depending on the type used. The tiny T-shaped device, which must be inserted into the uterus by a health provider, prevents pregnancy by stopping sperm from reaching an egg. It is considered to be the most effective form of birth control, with a failure rate less than 1 percent.

IUDs can cost up to $1,000, but under the Affordable Care Act, women with insurance could get one without paying a hefty cost. Many women, however, were concerned about the loss of this benefit if the ACA is repealed. In the first weeks after the presidential election, Planned Parenthood saw a nearly tenfold increase in women seeking IUDs.

There are four kinds of hormonal and one nonhormonal IUD. Hormonal IUDs use progestin, a synthetic form of the hormone progesterone produced naturally by the female body, to halt ovulation and thicken the uterine lining. These last for three to five years. The nonhormonal IUD, which can last up to 10 years, is made of copper. The copper causes an inflammatory reaction in the uterus that makes it difficult for sperm to survive.

IUDs are known to cause mild side effects in the first few months of use, ranging from moderate pain when first inserted to heavier menstrual cycles.

If you’re interested in getting an IUD, consult your doctor. He or she can help you determine if, and what type, of IUD may be the right fit for you.