why can't you take ibuprofen when pregnant

Ibuprofen is generally not recommended during pregnancy, especially after 20 weeks, due to risks it poses to the developing baby. Taking ibuprofen after mid-pregnancy can cause premature closure of the ductus arteriosus, a vital fetal blood vessel that allows blood to bypass the lungs. If this vessel closes too early, it can lead to serious lung problems such as pulmonary hypertension in the newborn. Additionally, ibuprofen can reduce amniotic fluid by affecting the fetal kidneys, which is important for cushioning and lung development. There might also be an increased risk of miscarriage if taken early in pregnancy, and potential risks of birth defects though evidence is less conclusive. Because of these risks, ibuprofen is usually avoided during pregnancy unless specifically prescribed by a doctor, and safer alternatives like paracetamol (acetaminophen) are recommended for pain relief.