How Placenta Nourishes Fetus

The development of a baby follows a predictable path from conception to the birth. As cells divide and differentiate, the developing baby starts as an embryo, forms into a blastocyst, becomes an embryo and then transforms into a fetus, all in the first trimester of pregnancy. From the very beginning, the placenta serves a critical role, supporting the survival and growth of the fetus throughout most of the 9 months of pregnancy.

Placenta

The placenta, which is also known as afterbirth is an temporary organ that joins the mother and fetus, transferring oxygen and nutrients from the mother to the fetus and permitting the release of carbon dioxide and waste elimination, nutrient uptake, provides thermo-regulation to the fetus, fight against internal infections, produce hormones to support pregnancy, and gas exchange via the mother's blood

supply system. After the formation and it's attachment to the uterus, umbilical cord develops from the placenta. The umbilical cord is what connects the mother and the fetus.

The placenta is a unique organ because it is only present during pregnancy. It nourishes the fetus while it's still in the womb and is then expelled after the baby born. Learn how the placenta grows and develop.

• Filtering

In the womb, the placenta can act like the kidneys. Before the blood from the mother goes into the fetus, it passes into the placenta. This blood contains things the fetus needs, like oxygen, glucose, and other nutrients. But, it can also contain some substance that could harm the fetus. Fortunately, the placenta acts like a kidney and filters out harmful substances before they reach the fetus.

• Hormones 

The placenta is responsible for the production of several important hormones, including progesterone, estrogen, placental growth hormone and placental lactogen. Although most hormones made by the placenta do not influence the fetus directly, instead they perform their work indirectly by regulating the mother responses to pregnancy. For instance, progesterone helps uterine walls to thicken and grow and stimulates glands in the lining to make nutrients used by the embryo during the early stages of pregnancy.

• Nutrition and Excretion

The attachment between intervillous spaces of the placenta with maternal blood allows the transfer of oxygen and nutrients from the mother to the fetus and the transfer of waste products back into the maternal blood from the fetus, which mainly includes metabolic wastes. It occurs via both active and passive transport. Waste products excreted from the fetus such as urea, uric acid, and creatinine are also transferred to the maternal blood by diffusion across the placenta.

Interesting Facts.

• During pregnancy, every minute 568.26ml of blood is pumping into the uterus, exchanging nutrients with the placenta. 
• Babies do not breathe amniotic fluid. Oxygen diffuses across the placenta into the foetal blood, which then travels through umbilical cord into the baby's circulation.
• The placenta has no nerve cells and therefore is not directly under the control of the brain and spinal cord.