Blighted Ovum

Chances are you didn’t even know you were pregnant or had just found out you were expecting when you received the shattering news that there is no visible developing embryo on the ultrasound. You are probably feeling sad and confused. As you take time to understand what this means, also take time to grieve as you would for any loss. And remember you are not alone.

What is a blighted ovum?
A blighted ovum (also known as “anembryonic pregnancy”) happens when a fertilized egg attaches itself to the uterine wall, but the embryo does not develop. Cells develop to form the pregnancy sac, but not the embryo itself. A blighted ovum usually occurs within the first trimester before a woman knows she is pregnant. A high level of chromosome abnormalities usually causes a woman’s body to naturally miscarry.

How do I know if I am having or have had a blighted ovum?
A blighted ovum can occur very early in pregnancy, before most women even know that they are pregnant. You may experience signs of pregnancy such as a missed or late menstrual period and even a positive pregnancy test. It is possible that you may have minor abdominal cramps, minor vaginal spotting or bleeding. As with a normal period, your body may flush the uterine lining, but your period may be a little heavier than usual.

Many women assume their pregnancies are on track because their hCG levels are increasing. The placenta can continue to grow and support itself without a baby for a short time, and pregnancy hormones can continue to rise, which would lead a woman to believe she is still pregnant. A diagnosis is usually not made until an ultrasound test shows either an empty womb or an empty birth sac.

What causes a blighted ovum?
A blighted ovum is the cause of about 50% of first trimester miscarriages and is usually the result of chromosomal problems. A woman’s body recognizes abnormal chromosomes in a fetus and naturally does not try to continue the pregnancy because the fetus will not develop into a normal, healthy baby. This can be caused by abnormal cell division, or poor quality sperm or egg.

Should I have a D&C or wait for a natural miscarriage?
This is a decision only you can make for yourself. Most doctors do not recommend a D&C for an early pregnancy loss. It is believed that a woman’s body is capable of passing tissue on its own and there is no need for an invasive surgical procedure with a risk of complications. A D&C would, however, be beneficial if you were planning on having a pathologist examine the tissues to determine a reason for the miscarriage. Some women feel a D&C procedure helps with closure, mentally and physically.

How can a blighted ovum be prevented?
Unfortunately, in most cases a blighted ovum cannot be prevented. Some couples will seek out genetic testing if multiple early pregnancy loss occurs. A blighted ovum is often a one time occurrence, and rarely will a woman experience more than one. Most doctors recommend couples wait at least 1-3 regular menstrual cycles before trying to conceive again after any type of miscarriage.

Last Updated: 12/2006

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Compiled using information from the following sources:

Current Obstetric & Gynecologic Diagnosis & Treatment-Ninth Ed. DeCherney, Alan H., et al, Ch. 14.

Source: http://www.americanpregnancy.org/pregnancycomplications/blightedovum.html