Anencephaly is a rare, irreversible congenital condition wherein a part of the baby’s skull and brain do not form during the first trimester of pregnancy. It is a neural tube defect (NTD) that results from the neural tube not closing in the first three or so weeks after conception (neural tubes normally close between Day 23 to 26 following conception). Approximately 1 in every 1,000 pregnancies is diagnosed with anencephaly, often leading to miscarriage.