Screening for Hemoglobinopathies
Hemoglobinopathies are a group of genetic disorders and diseases that affect hemoglobin, the protein in red blood cells responsible for carrying oxygen. Screening for these blood disorders prior to pregnancy can help identify parents at a higher risk of having a child with a hemoglobin disorder.
Hemoglobinopathies are inherited conditions passed from a parent to a child. To help identify parents that are carriers for certain genetic conditions, reproductive endocrinologists look to a couple’s racial or ethnic background, family health history and personal medical history. Couples that are carriers for hemoglobinopathies should receive reproductive and prenatal diagnosis counseling.
Conditions Associated with Hemoglobinopathies
The two major types of hemoglobinopathies are related to structural defects that cause hemoglobin to form improperly and diminished production of hemoglobin that leads to anemia, or hemoglobin deficiency.
Thalassemia and Sickle Cell Disease are some of the most common genetic disorders in the world. Since cost makes universal hemoglobinopathy screening unrealistic, the American College of Obstetricians and Gynecologists recommends individuals of Mediterranean, African and Southeast Asian descent (the groups at highest risk for the disorders) undergo hemoglobinopathy carrier screening prior to pregnancy.
Hemoglobinopathy Screening Guidelines
Blood tests are performed to see whether or not the mother-to-be is a carrier for the genetic conditions. Hemoglobin electrophoresis, a blood test to check the different types of hemoglobin is done to identify women who carry the trait for Sickle Cell Disease.
Screening for the Thalassemias requires a complete blood count (CBC) with mean corpuscular volume (MCV). Hemoglobin electrophoresis follows if the MCV level is suggestive of thalassemia.
Genetic Counseling for Hemoglobinopathies
Fertility specialists recommend genetic counseling for parents who are carriers of hemoglobin disorders. This helps parents understand the specific disorder and how it may affect their baby. Genetic counseling also provides information on treatment and reproductive options.
Preimplantation Genetic Diagnosis for Hemoglobinopathies
If both parents are found to carry a hemoglobinopathy, their children will be at increased risk of being affected with a more severe form of the disease. Following genetic counseling, the couple may opt to undergo in vitro fertilization (IVF) with preimplantation genetic diagnosis (PGD) to determine if their embryos are affected by the disease or not. Only an unaffected embryo would subsequently be transferred back to the uterus.