Placenta: Development & Function During Pregnancy

Placenta: Development & Function During Pregnancy

If you are pregnant or have been trying to get pregnant, words like placenta, amniotic sac, umbilical cord are probably already a huge part of your everyday vocabulary. However, do you exactly know what a ‘placenta’ is? Do you know the function of the placenta? Read on to find out all you need to know about the functions of the placenta.

What is a placenta?

The placenta is an organ that develops in the uterus and supports the normal growth of the fetus. It is responsible for the exchange of nutrients from the mother to the baby. It usually attaches itself to the top of the side of the uterus and is connected to the baby by the umbilical cord. The umbilical cord carries the nutrients from the placenta directly into the baby’s bloodstream. Also read: All that you need to know about Low Lying Placenta during Pregnancy It also provides oxygen to the fetus while removing carbon dioxide and other waste products. In addition to these, it releases hormones to aid pregnancy, primarily the metabolic functions, fetal growth, and childbirth. The placenta accounts for about 1 kg of the weight you gain during pregnancy. Generally, within 30 minutes of a baby being born, the mother will also deliver the placenta in a process called “afterbirth”.

How does the placenta develop?

After conception, the fertilised egg needs a way to use the mother’s nutrients. The egg then travels to the end of the fallopian tube and enters the uterus searching for the uterine wall. This trip that the egg takes can be tricky because if the egg doesn’t implant itself successfully, the uterine wall will start to shed and there will be no pregnancy. If the egg implants itself in the uterine wall, the placenta begins to develop. The placenta usually starts to form about a week after conception.

Functions of the placenta:

#1. It gives nutrition to the baby

Did you know that the food you eat doesn’t go directly to your baby? Your body breaks down the food you eat into nutrients that enter your bloodstream. The nutrients in your bloodstream are then passed on with the help of the placenta and the umbilical cord into the baby’s bloodstream.

#2. Blood supply

All throughout your pregnancy, the placenta helps blood to be sent to the uterus to exchange nutrients. Keep in mind that alcohol too can pass to your baby via the placenta, so quit drinking or any other bad habit like smoking or drugs right away. This is one of the most important functions of the placenta. Also read: Everything You Need To Know About Stem Cell Banking

#3. Provides oxygen for the baby

Let’s look at it this way, when you are breathing, it means that you are breathing for your baby as well. As your baby’s lungs are developing, the placenta gives the baby all the oxygen he needs. The baby swallows and inhales amniotic fluid but he does not receive oxygen. Hence, the placenta carries the oxygen required to the umbilical cord to be passed into the baby’s bloodstream.

#4. The placenta produces necessary hormones

The placenta also acts a gland that secretes all the hormones that are necessary for the normal development of your baby as well as to prepare for breastfeeding. Some of the essential hormones are Human Chorionic Gonadotropin (hCG), estrogen, progesterone and human placental lactogen.  

#5. Provides immunity and protection from infections

The placenta can protect the baby from infections while in the womb. If the mother has a bacterial infection, the placenta helps protect the baby from getting the infection. The baby also receives antibodies from the placenta. These antibodies provide the baby with immunity for the baby’s early months. However, in case of serious or viral infections, the placenta might not protect the baby.

Also read: 10 Most Common Complications During Pregnancy

#6. Helps in preparing breast milk

It may not be the placenta itself that is creating breast milk but when the placenta is separated from the baby, it triggers the production of prolactin. Prolactin is a hormone which is responsible for the production of milk.

Risk factors that can influence the placenta:

  • History of smoking, excessive drinking or drug abuse High blood pressure
  • Carrying twins or more
  • Ethnicity
  • Blood-clotting disorders
  • Previous C-section delivery
  • History of placental problems
  • Age factor (if women are over the age of 40)

Common disorders of the placenta

#1. Placenta previa

It is a condition in which the placenta attaches itself very low to the wall of the uterus. Due to this, the placenta partially or completely covers the cervix. It is generally a condition that occurs during the third trimester and may resolve on its own as the pregnancy progresses. It can also cause bleeding, placental tears, an increased risk of fetal infection and preterm labour. More often than not, a cesarean delivery is recommended. Also read: Tests & Scans Before & During Pregnancy

#2. Placenta abruption

It is a disorder in which the placenta separates from the uterus during pregnancy. The abruption can happen either partially or completely. Like the placenta previa, this condition also generally occurs during the third trimester.

#3. Placental insufficiency

As mentioned above, the placenta is extremely important for the normal growth and development of the baby. However, sometimes, the placenta may not function properly and because of this, it may fail to provide an adequate amount of nutrients to the baby. This is what causes placental insufficiency. Women with this condition may notice less fetal movement and low birth weight in newborns.

#4. Placental infarcts

If there are areas of dead tissues found inside the placenta, the condition is called placental infarcts. It is generally caused by complications and issues in the blood vessels. This condition decreases the flow of blood to the affected areas. It may hinder the growth of the fetus. Women who have high blood pressure are more at risk to suffer this condition. Also read: C-section versus Natural Delivery – Risks and Benefits

#5. Placenta accreta

It is a serious condition, but not a common one. The placenta grows deep in the wall of the uterus. There are three forms of this disorder - (a) The placenta accreta, in which the placenta is attached to the uterine wall muscle, (b) The placenta increta in which the placenta goes into the uterine walls and, (c) The placenta percreta in which the placenta grows into the uterine wall and attaches itself to surrounding organs. Want to share your experience as a mom with other moms through words or images? Become a part of the Moms United community. Click here and we will get in touch with you