Before Getting an IUD, Read What a Doctor Has to Say About the Potential Side Effects

An IUD (intrauterine device) is a small, flexible, T-shaped plastic device that's inserted directly into your uterus to prevent pregnancy. There are five different brands of IUDs: the nonhormonal copper IUD, Paragard, and a few different hormonal versions, including Mirena, Skyla, Kyleena, and Liletta, which release the hormone progestin to prevent pregnancy. Paragard lasts up to 12 years, while the hormonal versions are effective for anywhere from three to seven years.

The side effects you can experience with an IUD depend on which type you choose.

For any kind of IUD, the most common side effect is changes in menstrual bleeding, said Laura Pineiro, MD, an ob-gyn with Northwestern Medicine. With the Paragard in particular, she said, the main side effect will be intense cramping, particularly in the first few months as your body gets used to the IUD. You'll also continue to have a regular period but may have a heavier flow. "You'll have a period every month, but just heavier and more crampy periods," Dr. Pineiro told POPSUGAR.

IUD insertion, whether for Paragard or a hormonal IUD, is also likely to come along with pain and some cramps for a day or two afterward. Read more about the insertion process and side effects here.

With a hormonal IUD, Dr. Pineiro said, the most common side effect is irregular spotting. Your period flow might lighten, and for about 20 percent of women, Dr. Pineiro said, it can go away altogether (a nice side effect!). Even in that case, you may still experience occasional spotting.

Because Mirena, Skyla, Kyleena, and Liletta all use hormones, some other side effects might crop up as well. These can include:

While many IUD side effects are normal, Dr. Pineiro noted that there are some that you may want to take a trip to the doctor to sort out. In general, you should look out for any major changes in your flow, post-IUD insertion, which could indicate an issue. Keep an eye out for extremely heavy flow in particular, Dr. Pineiro said: saturating a pad or tampon every hour or two, for more than three or four days in a row. Treatment for abnormal bleeding may be a temporary dose of hormones. "I've had patients that have required a dose of birth control pills for one month just to help regulate it a little bit," Dr. Pineiro explained. "After that, if we've stopped the pill, it usually improves or solves the problem."

Expulsion and perforation are both big concerns for people considering an IUD. Expulsion, or the IUD "falling out" of your uterus, occurs in .05 to eight percent of patients, Dr. Pineiro said. It's most common during that time of intense cramps right after the insertion. "There's a foreign object inside of you, and the way the uterus responds to that is by cramping," Dr. Pineiro told POPSUGAR. Those strong cramps can expel the IUD.

After that initial postinsertion timeframe, the most common reason an IUD is expelled is if you're having very heavy menstrual flow, which can cause the IUD to be pushed out along with the uterine lining.

Perforation typically happens if the IUD isn't put in correctly during insertion. If the doctor tries to insert the IUD or the insertion device too quickly, Dr. Pineiro explained, you can pierce the muscle of your uterus, causing perforation. The main symptom of it is pain that doesn't quickly dissipate over the hours postinsertion. "The insertion itself is painful," Dr. Pineiro said, but "it should be getting better every few minutes that go by." If the pain worsens over that day or the next, it could be a sign that the IUD has perforated the uterus.

Dr. Pineiro said it's very unlikely for the IUD to perforate postinsertion because of its soft, flexible nature. "It's not this device that's made out of a metal that's going to perforate through," she explained.

The decision to get an IUD is a big one, and there are lots of pros and cons to take into account. Getting educated on the possible side effects, the insertion process, and more can help you make the most informed decision possible and choose the right form of contraception for you.