When it comes to pregnancy prevention, IUDs are nearly fail-safe—which helps explain why they've become the hottest thing in contraception. Once an IUD is in, it works for years with greater than 99% efficacy. But getting it in is what makes some women nervous. A gynecologist needs to insert the T-shaped device into your uterus, a process that is typically quick and not very painful, says Health's medical editor, Roshini Rajapaksa, MD. But because no two IUD experiences are exactly alike, we reached out to real women for their personal stories. Here, they share what they felt during the insertion, and whether they would choose to do it again.

“It felt like I’d done a serious strength training regimen just with my pelvis.” —Allyson W., 31, college instructor

Allyson switched to an IUD because she was tired of having to think about birth control everyday. “My OBGYN recommended Mirena for its low side effects, and I decided to go for it,” she says. But the insertion process wasn't what she expected: “I have a small cervix. I was given drugs to help it dilate … but they just did not work at all. In fact, I had an allergic reaction to them. The nurse practitioner had to manually dilate my cervix to insert the device," she explains. “It was so painful, and I thought I was going to pass out!” But Allyson has no regrets, and has since gotten her first IUD replaced. “I haven't had any side effects, I never need to remember to take a pill, and I know I'm using a very reliable form of contraception. I'll probably get a third in 2018.”

RELATED: 20 Weird Facts About Sex and Love

“I love the ‘set it and forget it’ mentality.” —Danielle L., 30, general manager

Danielle describes her IUD insertion as "the single biggest, most intense cramp of my life." The pain, however, didn't last long. There was some lingering abdominal discomfort afterward, but "nothing too bad." When her IUD expires, she plans to have it replaced. "Whatever the cost—both financially and the physical pain of the insertion—it's totally worth it in my opinion," she says.

"If you’ve ever had a PAP smear, the cramps I felt were like those cramps, but five times worse.” —Gina V., 22, marketing coordinator

Gina thinks her anxiety about the insertion made it feel more painful: “I [had] read every online review I could find. I [had] completely psyched myself out, and almost didn't get it.” Gina's emotional distress during the process triggered a vasovagal reaction—a sudden drop in heart rate and blood pressure that reduces blood flow to the brain. “My whole body was shaking and quickly alternating between hot and cold, I was slightly nauseated and very dizzy and faint,” she says. But Gina believes her experience was rare: “A lot of woman have really easy, great experiences with the IUD. I'm just not one of those women.”

“In retrospect, 10 minutes of discomfort seems insubstantial to five years of effective birth control.” —Lauren G., 24, financial analyst

During her appointment to have her IUD inserted, Lauren learned that her uterus was tilted, and that the process would take about 10 minutes (five times longer than usual). “When the IUD was inserted, the pain was comparable to very intense period cramps,” she said. “They were most prevalent during the insertion, but did not go away completely for a few days.” She was surprised by how long it took her body to adjust to the device. “I was bleeding intermittently for about four months,” she said, which "was more of an annoyance than anything.” Still, Lauren says, she wouldn't hesitate to make the same choice again.

RELATED: 16 Things You Must Know About Sex After Pregnancy

“All clothing with a waist band caused me pain.” —Ashley B., 31, communications manager 

Ashley initially chose a copper IUD (the only type of LARC that doesn't release progestin) to avoid the common side effects of hormonal birth control methods (think weight gain and mood swings). She was attracted to the idea of a long-term solution that wouldn't cause much of a reaction in her body. But after suffering through a month of pain, she opted to have her IUD taken out. She says her doctor suggested it was possible her uterus was too small for the device.

"The peace of mind I have of not worrying about purchasing birth control monthly is worth it.” —Jerlyn T., 30, senior art director

Jerlyn made the decision to get an IUD from a cost perspective: “The price and the percentage of effectiveness made sense to me,” she says. “If it cost $500 for 5 years it would be like paying less than $10 per month.” For her, the insertion process was akin to PMS. “I felt some mild cramping," says Jerlyn, who plans to have her device replaced when it expires. “I love that I spend less [money] than men for contraceptives,” she said. The fact that she used to spend a lot more than men had to "always hit a nerve with me.”