Common Genetic Defects and Chance of Recurrence
|Down Syndrome||Congenital Heart Defects||NTD, anencephaly, spina bifida||Tay-Sachs Disease||Cystic Fibrosis||Sickle Cell Anemia||Muscular Dystrophy||Fragile X Syndrome|
|1%, goes up with already elevated risk||Ranges from 1.5% to 5 %, depending on type of CHD in first child||2% to 5% risk, depending on the baseline population risk.||25% recurrence risk in each pregnancy||25% recurrence risk in each pregnancy||25% recurrence risk in each pregnancy||25% recurrence risk in each pregnancy||25% recurrence risk in each pregnancy|
PreventionIn the case of neural tube disorders, if the cause is not genetic or resulting from factors that cannot be changed, such as teratogenic exposures or chronic maternal health problems, making positive changes to the mother’s diet and lifestyle (such as taking folic acid supplements before and during pregnancy) can play a role in preventing a second occurrence of NTD. Unfortunately, there is no way to guard against other genetic disorders.
Genetic ScreeningIf you have had one pregnancy resulting in a child with a genetic defect, you may wish to have genetic screening done on yourself and your partner to determine if you are carriers of any genetic defects. You may also wish to have any subsequent pregnancies genetically screened to determine if the fetus has any genetic irregularities. If you are undergoing IVF, you may opt to have preimplantation genetic diagnosis performed in order to ensure that only those embryos free of genetic problems are implanted.
These tests are not mandatory and any decisions made as a result of the tests will be left in your hands. For more information, please see our article on genetic counseling.