If hypothyroidism occurs during pregnancy, it does not necessarily affect the child’s IQ. If a woman has hypothyroidism during pregnancy, it is true that it may affect her child’s IQ, but this is a matter of chance and does not necessarily affect all children, so if hypothyroidism occurs during pregnancy, it is possible that the child will be stupid, but not all children will be stupid. If a pregnant woman’s hypothyroidism is controlled in time and her thyroid function is normal during preparation for and during pregnancy, then this condition has no effect on the child’s IQ. However, if the abnormal thyroid function is not controlled in time, then it may affect the neurological development of the fetus, and may have some effect on the intelligence of the fetus. Therefore, hypothyroidism during pregnancy must be treated in a timely manner under the guidance of a doctor.