In the first half of her pregnancy, a woman in most developed countries will be offered prenatal genetic screening. The idea is that a sample of the woman’s blood will show whether or not her baby is at risk of Down syndrome or other potentially disabling conditions.
Depending on the condition, the overwhelming majority of women opt to terminate if testing shows the fetus has a high chance of having a genetically related disability.
Not everyone does choose to terminate. Some just want advance knowledge so they can prepare, emotionally and practically, to have a child with a significant medical condition or disability. If the condition requires special management during pregnancy, or if targeted early treatment is possible, this knowledge can also be clinically useful.
