My girlfriend and I both have sickle-cell trait in our blood. Is there any way to ensure that our children will not have sickle-cell anemia?

Khalid

Sickle-cell anemia is a condition affecting a small percentage of African-Americans that results in painful, life-threatening blood clotting and infections. The red blood cells have an abnormal oxygen-carrying hemoglobin molecule that can cause the cell to change from its normal disc shape to a sickle shape that can get trapped in small blood vessels.

An individual with sickle-cell disease has two abnormal hemoglobin-S genes -- one from each parent. Individuals who do not have the disease but have one abnormal hemoglobin-S gene are said to have sickle-cell trait. This can be checked with a simple blood test. If both parents have sickle-cell trait, there is a 50 percent that an egg will carry the abnormal gene and a 50 percent chance that a sperm will carry the abnormal gene. This equates to a 25 percent chance that the resulting child will have sickle-cell anemia.

Genetic tests offer opportunities to diagnose this condition after conception. For couples using in vitro fertilization (IVF), an embryo biopsy can be performed before transferring the embryo into the mother's uterus. Parents may then choose not to transfer embryos affected with sickle-cell. Other couples may choose to conceive normally and undergo chorionic villus sampling, a small biopsy taken from the placenta at about nine or 10 weeks of pregnancy. The cells can be checked and a diagnosis made in two to three days. Parents may then consider elective pregnancy termination if the fetus is affected.

In other words, if you use your own eggs and sperm, the only certain way to avoid having an affected child is either by using IVF or having an abortion when an affected child is diagnosed during pregnancy. However, using a sperm or egg donor without sickle-cell trait can eliminate this risk.