You might not be familiar with this intrauterine device, but the IUD is making a name for itself in the realm of birth control. These days, the IUD is the most popular form of contraception used worldwide.

There are two types: hormonal and copper. The hormonal version, Mirena (currently the only brand on the market, with no generic version available), is a small, T-shaped, plastic device inserted by your doctor during an office visit and is left inside the uterus; the insertion procedure only takes a few minutes. This IUD releases progestin that thickens cervical mucus to block sperm from entering the cervix and thins the endometrium. Mirena is 99% effective at preventing pregnancy. You can try to conceive as soon as the device is removed.

Mirena is good for up to 5 years and then needs to be replaced. You'll need to see your doctor 3 months after the IUD has been placed to make sure it's in proper position.; after that it's checked at your annual exam. Side effects include increased bleeding or spotting at the start but over time periods usual become lighter and shorter. Some women experience monthly periods while 20% report none at all. It's a good option for women who are breastfeeding and those who are smokers or have health issues such as diabetes with complications, high blood pressure, or migraines with auras for all of which estrogen can increase the risk of blood clots, leading to a heart attack or stroke.

The copper IUD, ParaGard, is also made of flexible plastic but is coated in copper. As it releases copper into the uterus the mineral prevents the egg from becoming fertilzed and helps keep an egg from implanting into the uterus. The copper IUD is 99% effective at preventing pregnancy. A woman can become pregnant when the device is removed.

This IUD can be left in place for 10 years and also require annual office checks. Occasionally some women report they experience an increase in cramps and bleeding but it lessens over time. You get the same period you would monthly since it's not a hormone-based contraceptive. (This also makes it a good consideration for women who are breastfeeding).

With both devices, make sure to tell your physician about any heavy bleeding, abdominal pain, fever or chills as it's possible in rare cases for an IUD to shift and attach to or pierce your uterus, causing scarring or an infection. If this happens, the IUD will not prevent against pregnancy. You'll also be responsible for checking the IUD's placement monthly as instructed by your doctor. Your OB should show you how to locate the small threads that are attached to the bottom of the device and can be felt just outside your cervix.