by Dotun Ogunyemi, MD and Craig L. Bissinger, MD, FACOG
What is a still birth?
A still birth is a baby that is born after 20 weeks of pregnancy with no signs of life. Before 20 weeks, it's usually called a miscarriage.
Still births occur about four to nine cases for every 1,000 births. In areas that are not very high risk usually occurs about four in every 1,000 births. In areas of high pregnancy risk, it occurs in about nine in every 1,000 births.
What are some of the common causes of still birth?
Still births may occur because of a problem with the baby. One of the commonest problems with the babies that are born still birth are babies of a chromosome abnormality. Normal people are 45 chromosomes. Some babies are found with either too many or too few chromosomes. This results in a still birth.
Another problem with a baby is if the baby has a birth defect. Birth defects could affect the brain, their heart or the kidneys or any parts of the baby. If a baby is found with a birth defect, that quickly increases the chance that a baby may not survive.
Other causes may include infection. If the mother has an infection of syphilis, toxoplasmosis, a cytomegalovirus -- this effects the baby, may cause the baby not to survive. Sometimes the mother's membranes are ruptured and bacteria from the vagina may actually rise into inside of the womb and this may effect the baby and this may also make the baby not survive.
Problems of the mother can also result in the baby not surviving. If the mother has significant disease like severe hypertension, diabetes that has not been controlled, this can effect the pregnancy. Sometimes some mothers form antibodies that effect their pregnancy. The most common one is called the antiphospholipid antibodies and this may be associated with the baby not surviving.
If the mother used any kind of drugs, for example, alcohol -- too much alcohol can effect the baby. Cigarette smoking may also do the same thing and especially drugs like cocaine can definitely effect the baby. Occasionally there may be some accident in which the baby starts bleeding into the mother and that may make the baby not survive.
Sometimes the placenta itself may have a problem, either the placenta separates suddenly or sometimes the placenta is so poorly formed that it is not working well. Very rarely you might have a problem with the baby's cord. The baby's cord may become entangled or form a knot, and if there is a knot then blood cannot flow to it and this can result in the baby not surviving.
How is a still birth diagnosed?
To make a diagnosis of still birth usually the mother comes and says the baby has not been moving. This is why it's very important for pregnant women to note how often their babies move. After the mother comes and says the baby is not moving, we usually do an ultrasound and on ultrasound you can either see that the baby is not moving at all or the cessation of the heart movement.
What kind of testing is done?
DOTUN OGUNYEMI, MD: We usually do the diagnosis by ultrasound and on ultrasound you can look at things that can help you detect what may be wrong with the baby. On ultrasound, you can look to see whether there are any obvious defects of the baby like, for example, maybe the baby's heart does not look normal or the baby's brain does not look normal, or there is something wrong with the kidneys or with the baby's abdomen.
Also you can look at the amount of fluid around the baby. If the amount of fluid around the baby has decreased, that may suggest that the placenta is not working well. If the fluid around the baby has increased, that may suggest that the baby has a chromosome abnormality.
Finally, while doing the ultrasound, we can offer the amniocentesis to the mother. The amniocentesis is the procedure that withdraws a few drops of fluid from around the baby. This can be sent to the lab to check for the baby's chromosomes, so you can know whether the baby has a chromosome abnormality or not. This can also be sent to check for the various infections like the toxoplasmosis and the cytomegalovirus that I mentioned because this may also have an effect on the baby's surviving.