Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Ectopic Pregnancy


The Manual's Editorial Staff

Reviewed/Revised May 2023
Get the full details
Topic Resources

What is an ectopic pregnancy?

  • An ectopic pregnancy is when a fertilized egg attaches in the wrong place, such as in the fallopian tubes

  • An ectopic pregnancy does not result in a baby being born

  • If not diagnosed and treated promptly, it can cause life-threatening bleeding in the woman

In a healthy pregnancy, a sperm enters (fertilizes) an egg while the egg is in one of your fallopian tubes. Your fallopian tubes connect your ovaries (where your eggs are stored) with your uterus (womb). The fertilized egg, which is in a sac, then moves into your uterus and attaches there to grow.

Ectopic Pregnancy: A Mislocated Pregnancy

Normally, an egg is fertilized in the fallopian tube and becomes implanted in the uterus. However, if the tube is narrowed or blocked, the egg may move slowly or become stuck in the fallopian tube. The fertilized egg may never reach the uterus, resulting in an ectopic (mislocated) pregnancy.

An ectopic pregnancy may be located in many different places, including a fallopian tube, an ovary, the cervix, and the abdomen.

Ectopic Pregnancy: A Mislocated Pregnancy

In an ectopic pregnancy, the fertilized egg doesn’t attach in your uterus. Instead, it attaches somewhere else. It may attach in one of your fallopian tubes, in the wall of your uterus, or in your belly outside your uterus.

  • The fertilized egg can't grow correctly outside of your uterus

  • The sac holding the egg will burst, usually after about 6 to 16 weeks from when you got pregnant

  • When the sac bursts, you bleed a lot

  • The fetus doesn't survive

  • Ectopic pregnancies can cause lower belly pain and vaginal bleeding

  • If not treated, an ectopic pregnancy is life threatening

  • Sometimes symptoms start before you even know you're pregnant

  • To save your life, doctors do surgery or give you a medicine to shrink the ectopic pregnancy

Ectopic Pregnancy

What are the symptoms of an ectopic pregnancy?

If the sac containing the egg hasn't burst, you may not have symptoms, or you may have:

  • Bleeding or spotting from your vagina

  • Cramping or pain in your lower belly

If the sac holding the egg bursts, you may have:

  • Intense, constant pain in your lower belly

  • Severe bleeding from your vagina (birth canal)

  • Severe bleeding inside your belly (where it can't be seen)

Severe bleeding can cause fainting, sweating, or a light-headed feeling. Your blood pressure could become dangerously low (a condition called shock Shock Shock is a life-threatening condition in which blood flow to the organs is low, decreasing delivery of oxygen and thus causing organ damage and sometimes death. Blood pressure is usually low... read more ), and you could die.

How can doctors tell if I have an ectopic pregnancy?

If you're of childbearing age and have lower belly pain or vaginal bleeding, faint, or go into shock, your doctor will do a pregnancy test. If the pregnancy test is positive or you know you're pregnant:

Ultrasound Ultrasonography Ultrasonography is a safe imaging test that uses sound waves to create a moving picture of the insides of your body. Ultrasonography doesn't use radiation (x-rays). Ultrasonography is also called... read more Ultrasonography uses sound waves to create moving pictures of your insides. Usually the doctor can see whether the pregnancy is in your uterus or not. However, if it's early in your pregnancy, the doctor may not be able to locate the fetus with the ultrasound. Then your doctor will decide what to do based on your symptoms and how much pregnancy hormone is in your blood.

If your symptoms are severe, the doctor may make a small cut just below your belly button and insert a viewing tube (laparoscope) to look for the ectopic pregnancy.

How do doctors treat an ectopic pregnancy?

An ectopic pregnancy must be ended as soon as possible to save the life of the woman.


If the ectopic pregnancy hasn't burst and is still small, doctors might give you a shot of a medicine called methotrexate. The medicine causes the ectopic pregnancy to shrink and disappear. Sometimes the methotrexate doesn't work and you'll need surgery.


Usually, they’ll do surgery to remove the ectopic pregnancy. Most often they do the surgery through a thin tube (laparoscope). If possible, your doctor will remove only the ectopic pregnancy.

If the ectopic pregnancy is in your fallopian tube, sometimes the doctor might have to remove the fallopian tube too.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Jylamvo, Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep
quiz link

Test your knowledge

Take a Quiz!