Intrauterine devices (IUDs) are one of the most common and effective forms of long-term reversible contraception, and the chances of pregnancy with an IUD are very low because it has a 99.7 percent effectiveness rate, says Ranalee Alava Sam, MD, an obstetrician-gynecologist in Fort Worth Lauderdale, Florida.
“Very few women who use IUDs become pregnant,” she points out, “but I always tell my patients that there is an exception — one in a million people on this planet — who do get pregnant with an IUD in place.”
Here’s what you need to know about symptoms of pregnancy with an IUD and possible complications if this unwanted outcome occurs.
Irregular menstruation and amenorrhea with IUD
Missed periods are often one of the first signs of pregnancy, but if you have an IUD, you may not be able to rely on that sign alone. About 25 percent of women who menstruate will stop having periods while using Mirena, an IUD that uses the hormone progesterone to prevent pregnancy, explains obstetrician-gynecologist Christina Perez, MD, of Houston Women’s Specialists at Texas Children’s and Women’s Hospital.
Paragard, another type of IUD, utilizes copper to prevent pregnancy. “Paragard is hormone-free,” Dr. Perez explains. So if you’re using Paragard, your period will continue unless you’re pregnant. Either way, if you miss your period on time and think you might be pregnant, it’s a good idea to contact your doctor and take a pregnancy test just to be sure.
Signs of pregnancy when using an IUD
Pregnancy with an IUD often causes the same symptoms as a normal pregnancy, such as breast pain, nausea, fatigue, etc. If you have early pregnancy symptoms and miss your period, take a pregnancy test and contact your healthcare provider.
It’s important to detect pregnancy early because of certain health issues. Home pregnancy tests are very accurate when used after your period is late, but they can’t detect pregnancy as early as a blood test in a doctor’s office or laboratory, so your doctor may recommend that you take a test to be sure.
Pregnancy Risk with IUD
Pregnancy with an IUD does come with certain risks and complications. “There’s a 50 percent higher chance of miscarriage if you leave the IUD in, so I would recommend continuing the pregnancy and removing the IUD,” says Dr. Sam. However, it’s important to note that there’s still a 25 percent higher chance of miscarriage even after the IUD is removed, so pregnancies with an IUD should be closely monitored by your doctor.
Pregnancies with an IUD also increase the risk of an ectopic, or tubal, pregnancy, in which the fertilized egg implants somewhere other than the uterus, usually in the fallopian tube. Ectopic pregnancies are nonviable and can be life-threatening to the woman, so they require prompt treatment. Doctors diagnose ectopic pregnancies with blood tests, a pelvic exam, and an ultrasound. Ectopic pregnancies are treated with medication or surgery.
Pregnancy after IUD removal
Research has shown that, unless there are underlying fertility issues, fertility returns quickly after IUD removal (good news for those hoping to conceive, warning for those who don’t!).
If you decide you want to become pregnant, contact your obstetrician-gynecologist to have the IUD removed and schedule a pre-pregnancy appointment. Some doctors recommend waiting three months after removing your IUD before trying to conceive to give your body time to return to a normal menstrual cycle. Waiting also gives you time to understand your menstrual cycle and fertile window, make a plan, and develop healthy habits.
But there’s no medical reason to wait, according to Dr. Perez: “You could ovulate the following month and get pregnant,” she says. So if you’re ready to become a parent and don’t want to wait, you can wait for your first period after removing your IUD.
