Amniotic sac

The amniotic sac (English: amniotic sac ) is the sum of the amniotic embryonic membranes, the fetal membranes. The embryonic membranes surrounding the embryo in all mammals during growth in the uterus. While in man only the amnion is the actual vesicle surrounds of many other mammals, the allantoic cavity of the fetus in all or in part.

At birth, the waters break ( rupture of membranes ) by the action of labor. An artificial opening of the amniotic sac is called amniotomy.

• Amniotic sac