Alternative Names anembryonic pregnancy, preclinical abortion
Definition A blighted ovum refers to a failure of the fertilised egg to develop in the first few weeks of pregnancy.
What is going on in the body? It is estimated that only about 2/3 of female eggs that are fertilised result in detectable pregnancies. The other 1/3 of fertilised eggs spontaneously abort or die. Another name for a female egg is an ovum. A blighted ovum usually occurs before a woman even knows she is pregnant.
What are the signs and symptoms of the condition? A blighted ovum often causes no symptoms at all. Symptoms and signs may include:
a missed or late menstrual period
minor abdominal cramping
minor vaginal spotting or bleeding
a positive pregnancy test at the time of symptoms
it is usually detected on an early ultrasound
What are the causes and risks of the condition? A blighted ovum is abnormal. Many of the fertilised eggs that die this early have severe genetic defects. These eggs cannot develop properly and do not develop further. This condition seems to occur more often in older women. Older women have a higher risk of delivering children with genetic disorders, such as Down syndrome.
The main risk of this condition is usually the mental distress caused by discovery that the woman is or was pregnant. Repeated early egg failures may indicate a genetic or physical disorder in the parents. Rarely, a specific problem may be causing multiple early egg failures, such as an autoimmune disease.
What can be done to prevent the condition? In most cases, nothing can be done to prevent this condition. In the case of repeated early egg failure, both partners may want to get genetic testing and genetic counselling.
How is the condition diagnosed? Occasionally this is diagnosed on an early ultrasound, often because of bleeding. Women usually don't know they are pregnant at the very early stage of pregnancy, a diagnosis is not made.
What are the long-term effects of the condition? The main long-term effects are related to mental distress. This is more often a problem if the condition occurs more than once, in which case it is very emotionally distressing to the people involved.
What are the risks to others? There are no risks to others, as this condition is not contagious. Those women with repeated early egg failures might have a genetic problem. This genetic problem may sometimes be passed on to the child if a regular pregnancy occurs.
What are the treatments for the condition? If repeated early egg failures occur, artificial fertilisation may be effective in producing pregnancy. Genetic testing may also be advised to rule out genetic problems. While these are not treatable, they may indicate the need for a sperm or egg donor in order to have children.
What are the side effects of the treatments? Hormones can cause side effects, such as headaches, mood swings, and others. Artificial fertilisation is expensive and does not always work. The risk of multiple births is often higher.
What happens after treatment for the condition? In most women, the diagnosis is never made and treatment is never needed. Most women who have a blighted ovum go on to have a healthy child the next time they get pregnant.
If treatment occurs and is successful, a regular pregnancy occurs. Adoption is another option for some couples.
How is the condition monitored? Most cases require no monitoring as women usually choose to have a suction curette to empty the uterus.
Author: Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
