How many liters of blood does a blue whale lose during childbirth?

Answer

During human pregnancy, the fetus settles in the wall of the uterus. The fetal part of the placenta (or placenta) also literally eats itself deep into the tissue of the uterus in order to end up in the mother’s blood vessels and to absorb the necessary nutrients from it.

At birth, the placenta must detach and the baby must also detach from the uterine wall. This is accompanied by a lot of tissue loss from the mother, which can cause (relatively much) blood loss during childbirth and the period afterwards.

During pregnancy in whales (which, like humans, are also mammals and not fish), the fetus remains in the internal cavity of the uterus and the fetal part of the placenta does not affect the uterine wall either. At birth, both the baby whale and the afterbirth can be easily squeezed out without loss of tissue from the mother, so that in principle no significant blood loss occurs.

The blood that you may see at the birth of a whale or dolphin comes from the torn umbilical cord through which the blood flows out of the amniotic membranes (the afterbirth).