Testing for Ectopic Pregnancy: How Doctors Make a Diagnosis

A normal, healthy pregnancy develops in a person's uterus. But around 2% of the time, an embryo implants somewhere else—usually in the fallopian tubes, but sometimes in the ovaries, abdomen, cervix, or previous C-section scar. This is called an ectopic pregnancy.

Left untreated, ectopic pregnancies could cause ruptured fallopian tubes, internal bleeding, and maternal death, according to Mark D. Levie, M.D., professor of OB-GYN and women's health at the Albert Einstein College of Medicine. With speedy diagnosis and treatment, however, a person probably won't have any complications. Here's what you need to know about the tests used to diagnose an ectopic pregnancy.

Would an Ectopic Pregnancy Show Up on a Home Pregnancy Test?

Since ectopic pregnancies still produce the hormone hCG, they'll register as a positive home pregnancy test. People with ectopic pregnancies will also experience early pregnancy symptoms like sore breasts, nausea, spotting, and more. The telltale symptoms of ectopic pregnancy (bleeding and abdominal pain) typically appear around 6-8 weeks, says Dr. Levie. That said, they can appear as early as 4-5 weeks.

Ectopic Pregnancy Testing and Diagnosis

If you experience abdominal pain or bleeding during the first trimester, you should see a doctor to rule out ectopic pregnancy. While cramping like a period may be common, it should be mostly in the midline; if your pain is significant or on one side, the possibility of an ectopic must be explored. This is especially important as an ectopic pregnancy progresses and causes bleeding in the abdomen which can result in lightheadedness, weakness, shoulder pain, fainting, and more as the blood loss becomes more significant. Getting a diagnosis early reduces the risk of complications like fallopian tube rupture and internal bleeding. Keep in mind that the probability of ectopic pregnancy is low, even with pain and bleeding, but it's best to have a high index of suspicion to rule it out.

Confirming the Pregnancy

Many people visit their doctor for abdominal pain and bleeding without knowing the cause. If the doctor thinks you may be pregnant, they'll test your blood or urine for human chorionic gonadotropin (hCG). Levels of hCG can be detected within 10 days of ovulation—although sometimes an increase can be detected earlier, sometimes even before you miss your period.

Quantitative hCG Test

Your health care provider may have already tested hCG levels to confirm a pregnancy. But according to Dr. Levie, they might also do a quantitative hCG test, which measures the exact level of hCG in the blood. Usually during pregnancy, hormone levels increase 40-100% every 48 hours, he says. "If this doesn't happen, then it could signal an ectopic pregnancy." What's more, hCG levels tend to be lower overall in an ectopic pregnancy. You may need to test hCG levels over a few days for definite results.

Note that if ectopic pregnancy symptoms are severe (intense pain, heavy bleeding, etc.) the doctor may immediately treat the ectopic pregnancy. Waiting for a diagnosis could put the pregnant person's health at risk.

Pelvic Exam

Your doctor might also conduct a pelvic exam. If they notice painful areas or a tender mass in the fallopian tube, they might suspect ectopic pregnancy. More testing is necessary to confirm the diagnosis. Pelvic exams could also rule out other causes of abdominal pain and vaginal bleeding.

Ultrasound

"We usually do an ultrasound to see if the pregnancy is in the uterus or outside the uterus," says Tracy Anderson, M.D., a Kaiser Permanente OB-GYN based in Lakewood, Colorado. Doctors may use an abdominal ultrasound or transvaginal ultrasound (a device placed into the vagina that creates images through sound waves). However, Dr. Anderson notes that pregnancy in the fallopian tube might have inconclusive ultrasound results, leading to the next ectopic pregnancy test. This is because you can't always see the pregnancy in the fallopian tube; that said, if you are past 5 weeks and your doctor can't detect the pregnancy in the uterus, they need to continue ruling out an ectopic pregnancy.

Positive Ectopic Pregnancy Tests: Now What?

If a doctor confirms ectopic pregnancy in the early stages, they will probably prescribe methotrexate to stop cell growth, says Dr. Anderson. But if the ectopic pregnancy is advanced or ruptured, surgery may be necessary to remove it.

Dr. Levie stresses the importance of early diagnosis of ectopic pregnancy. "Get to the doctor early in the pregnancy to confirm it's in the right place" if you have pain or bleeding, he says, adding that most pregnant people are unlikely to suffer complications with proper treatment.

Naturally, people have concerns about treating ectopic pregnancy after Roe v. Wade was overturned by the Supreme Court. Current state abortion laws allow exemptions for life-saving procedures, such as ectopic pregnancies—but given the chilling effects of anti-choice legislation, some providers may hesitate to treat, especially if there is some uncertainty whether an ectopic pregnancy is present. Make sure you advocate for yourself and speak with your doctor about any concerns you may have.