Disc-shaped organ in which materials are exchanged

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The placenta (Placenta) supplies your unborn baby with oxygen and nutrients and removes all waste products that the child's circulation produces. In addition, the placenta forms hormones that are necessary to maintain the pregnancy and keeps harmful substances, viruses and bacteria away from the child for the most part. Read more about the placenta here.

Origin and function of the placenta

The placenta develops in the first weeks of pregnancy from a part of the germinal vesicle that has emerged from the fertilized egg cell: finger-shaped, branched outgrowths (villi) develop on the outside of the cell cluster, which penetrate into the tissue of the uterus and connect with it. Together they form a disc-shaped organ - the placenta. So this develops from embryonic and maternal cells. It is connected to the child via the umbilical cord. In the course of pregnancy, it enlarges to a diameter of 15 to 20 centimeters, a thickness of two to four centimeters and a weight of about 500 grams.

The villi of the child's part of the placenta house the finest blood vessels and are bathed in maternal blood. This is where the exchange of substances between child and mother takes place: nutrients and antibodies are transported from the mother to the child and waste products are released from the baby into the mother's blood. Child and maternal blood are only separated from each other in the placenta by a very thin membrane, the so-called placental barrier. It acts as a filter and keeps bacteria and viruses off, for example, which could harm the child.

The placenta also produces proteins and hormones such as estrogen and progestin as well as HCG ("pregnancy hormone"), which is particularly important during pregnancy: it prevents the menstrual period from recurring, which would destroy the lining of the uterus. HCG thus serves to maintain and also as proof of pregnancy.

Placenta: Not everything bad is held back

However, not all pollutants can be filtered by the placenta and thus kept away from your child. The filter function cannot differentiate between substances that can harm your child and those that may be good. The distinction is made only between large and small molecules - the small ones are let through, the large ones withheld. The substances that can pass through the membrane include alcohol, nicotine and some medications - all of which are harmful to your child. On the other hand, maternal antibodies to fight pathogens also reach the child via the placenta and thus provide “nest protection”, which protects your baby from infections in the first few months after birth.

What affects the size of the placenta?

The size of the placenta is influenced by several factors. Smoking and the diet of pregnant women, for example, have an influence on the size of the mother cake. According to recent studies, stress on the expectant mother from external living conditions such as work, partnership problems or a difficult financial situation can also influence the size of the placenta.

However, it is not yet finally clear whether the size of the placenta affects the child's health and, if so, how. What is certain is that a placenta that is too small can impair the child's oxygen supply. With the help of Doppler sonography, a special form of ultrasound examination, your doctor can determine whether your child is under-supplied before it suffers any damage. A reaction of the child to an incipient undersupply can also be recognized via the “contraction recorder” (CTG) by recording the heartbeat.

Placental biopsy

A placenta biopsy is one of the methods of prenatal diagnosis (examinations on the unborn child): From the 14th week of pregnancy, a doctor can take a tissue sample from the placenta (puncture) in order to examine it for a variety of genetic diseases in the child. The tissue is usually removed through the abdominal wall, in exceptional cases also through the cervix.

Eat placenta?

In the animal kingdom, many mammal mothers eat the placenta after the birth of their offspring. In recent times it seems to be the fashion for women to eat the placenta after giving birth. This should, for example, prevent depression in the puerperium, relieve pain and bleeding after childbirth, promote the regeneration of the uterus, stimulate milk production, strengthen the mother-child bond and do your own skin good.

But none of this has been scientifically proven to date. If you also consider that the placenta, through its barrier function between mother and child, contains all filtered pollutants (including heavy metals), bacteria and viruses, then eating the placenta appears rather questionable.

Burying the placenta

The placenta is the most important interface between mother and child for nine months. Many new parents therefore do not want to simply dispose of the placenta after the birth: In Europe, the custom of burying the placenta and planting a tree for the newborn is widespread - a custom that is probably more popular than that Eating the placenta.

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