A 38 weaks pregnant lady delivered baby without upper limb. What can be the cause ?

Ans. is 'a' i.e., Amniotic bandIt is a case of limb reduction defect or congenital amputation in which there is defect in formation of a pa of limb or the entire limb.The exact cause of congenital amputation is unknown and can result from a number of causes. However, most cases show that the first three months in a pregnancy are when most bih defects occur because that is when the organs of the fetus are beginning to form.One common cause is amniotic band syndrome, which occurs when the inner fetal membrane (amnion) ruptures without injury to the outer membrane (chorion).Fibrous bands from the ruptured amnion float in the amniotic fluid and can get entangled with the fetus, thus reducing blood supply to the developing limbs to such an extent that the limbs can become strangulated, the tissues die and are absorbed into the amniotic fluid.