An ectopic pregnancy happens when a fertilized egg implants and starts growing somewhere outside the uterus, where it cannot develop into a viable pregnancy. It affects roughly 1 to 2 percent of all pregnancies and is the leading cause of death in the first trimester of pregnancy. An ectopic pregnancy always requires treatment, either with medication or surgery, because the growing tissue can rupture surrounding organs and cause life-threatening internal bleeding.
Where Ectopic Pregnancies Develop
The vast majority of ectopic pregnancies occur in a fallopian tube, which is why they’re sometimes called “tubal pregnancies.” But the location within the tube matters. About 70 to 80 percent implant in the wider middle section of the tube (the ampulla), roughly 12 percent in the narrow section closer to the uterus (the isthmus), and about 5 to 11 percent near the open end closest to the ovary (the fimbriae). A small percentage, around 2 to 3 percent, implant in the corner where the tube meets the uterus wall.
In rare cases, ectopic pregnancies develop entirely outside the tubes. About 3 percent implant on an ovary, and just over 1 percent attach somewhere in the abdominal cavity. Cervical ectopic pregnancies, where the egg implants in the cervix, are exceptionally rare.
Early Symptoms
Many ectopic pregnancies feel like a normal early pregnancy at first. You might have a missed period, breast tenderness, and nausea. These symptoms alone won’t signal anything unusual.
As the embryo grows in the wrong location, more distinctive signs appear. The most common early warnings are light vaginal bleeding (different from a normal period) and pain on one side of the pelvis. The pain may come and go or feel sharp and persistent. Some people also experience pain in the lower abdomen or lower back.
Signs of Rupture
If the growing tissue causes the fallopian tube to rupture, the situation becomes a medical emergency. Rupture causes sudden, severe pain in the abdomen or pelvis, often accompanied by heavy vaginal bleeding. Internal bleeding from a ruptured tube can lead to extreme lightheadedness, fainting, and shock.
One symptom that catches many people off guard is shoulder pain. When blood from a ruptured tube leaks into the abdomen, it can pool near the diaphragm and irritate the nerve that runs up to the shoulder. This “referred pain” has nothing to do with a shoulder injury. It’s a signal of internal bleeding. An urge to have a bowel movement, caused by blood collecting in the pelvis, is another less obvious warning sign. Any combination of these symptoms warrants immediate emergency care.
A UK report tracking maternal deaths between 2020 and 2022 found that twelve women died from ectopic pregnancies during that period. Investigators identified delayed diagnosis and failure to consider ectopic pregnancy in women who had collapsed as key factors in those deaths. Atypical presentations, where symptoms don’t follow the textbook pattern, contributed to the delays.
Risk Factors
Anything that damages or alters the fallopian tubes increases the chance that a fertilized egg will get stuck before reaching the uterus. A history of pelvic inflammatory disease, often caused by sexually transmitted infections like chlamydia or gonorrhea, is one of the strongest risk factors because the resulting inflammation can scar the tube’s inner lining.
Previous tubal surgery, including a prior ectopic pregnancy treated with surgery, also raises the risk. Smoking is a well-established factor: chemicals in cigarette smoke impair the tiny hair-like structures inside the tubes that help move the egg along. Using an IUD for contraception doesn’t increase your overall risk of ectopic pregnancy (because IUDs are very effective at preventing pregnancy entirely), but in the rare event that a pregnancy does occur while an IUD is in place, there’s a higher chance it will be ectopic. Assisted reproductive technologies like IVF are also associated with a slightly elevated rate, which partly explains why global ectopic pregnancy incidence has been trending upward alongside increased use of fertility treatments and rising maternal age.
How It’s Diagnosed
Diagnosis typically involves two tools used together: blood tests measuring pregnancy hormone levels and a transvaginal ultrasound.
In a normal early pregnancy, the level of the pregnancy hormone hCG roughly doubles every 48 hours. When doctors suspect an ectopic pregnancy, they’ll check your hCG level twice, about two days apart, to see how it’s changing. If the level rises by less than 66 percent over 48 hours, it’s a warning sign that the pregnancy may not be developing normally. When that sluggish rise is paired with an ultrasound showing nothing inside the uterus, the likelihood of an ectopic pregnancy is high. Conversely, if hCG levels drop by more than 50 percent, an ectopic pregnancy is less likely regardless of what the ultrasound shows, because the pregnancy is probably ending on its own.
On ultrasound, a doctor looks for whether a pregnancy sac is visible inside the uterus. An empty uterus combined with a positive pregnancy test and rising hCG is the classic combination that raises concern. Sometimes the ectopic pregnancy itself can be seen on ultrasound as a mass near the ovary or in the tube, but not always, especially very early on.
Treatment With Medication
When an ectopic pregnancy is caught early, before rupture, and the tube is still intact, medication can be an option. The treatment uses a drug called methotrexate, which stops the rapidly dividing cells of the pregnancy from growing. The body then gradually absorbs the tissue over several weeks.
Not everyone is a candidate for this approach. It works best when the ectopic mass is small (typically under 3 to 4 centimeters) and hCG levels aren’t extremely high. Patients with lower initial hCG levels generally receive a single dose, while those with higher levels may need a two-dose regimen. After treatment, you’ll need repeated blood tests over several weeks to confirm that hCG levels are falling back to zero. During this time, you may experience abdominal pain and cramping as the tissue breaks down, which can be unnerving but is usually normal.
You’ll also need to avoid alcohol, certain vitamins like folic acid, and sun exposure during the monitoring period, since these can interfere with how the medication works. Sexual intercourse and strenuous exercise are typically restricted until hCG reaches undetectable levels.
When Surgery Is Needed
Surgery becomes necessary when the ectopic pregnancy has ruptured, when hCG levels are very high, when symptoms are severe, or when medication has failed. Most ectopic surgeries are done laparoscopically, through small incisions in the abdomen, which means shorter recovery times.
There are two main surgical approaches. A salpingostomy makes a small cut in the tube, removes the ectopic tissue, and leaves the tube in place to heal on its own. A salpingectomy removes part or all of the affected tube along with the pregnancy. Complication rates between the two procedures are similar, around 18 to 20 percent, though recovery from a salpingostomy may be slightly shorter. The choice often depends on how much damage the tube has sustained and whether the other tube is healthy. If you have a functioning tube on the other side, removing the damaged one doesn’t significantly reduce your chances of conceiving naturally in the future.
In an emergency rupture situation, surgery may need to be done through a larger abdominal incision to control bleeding quickly. Recovery from open surgery takes longer, typically several weeks compared to a few days for laparoscopic procedures.
Fertility After an Ectopic Pregnancy
One of the first questions many people have after an ectopic pregnancy is whether they’ll be able to get pregnant again. The answer for most people is yes. Having one ectopic pregnancy does increase the risk of having another one, with estimates ranging from about 10 to 15 percent depending on the underlying cause and the treatment used. But the majority of people who have had an ectopic pregnancy go on to have successful pregnancies afterward.
Whether you were treated with medication or surgery, doctors typically recommend waiting at least two to three menstrual cycles before trying to conceive again. If you received methotrexate, the standard advice is to wait at least three months, since the drug can linger in tissues and potentially affect a new pregnancy. Once you do become pregnant again, your care team will likely schedule an early ultrasound to confirm that the pregnancy is in the right place, usually around six weeks.