Placenta

Definition

The placenta is a vital organ that develops in the uterus during pregnancy, serving as a connection between the mother and the developing fetus. It facilitates the exchange of nutrients, gases, and waste products, ensuring that the fetus receives essential supplies while also removing its waste. This organ plays a crucial role in supporting fetal development, regulating hormones, and providing immunological protection against infections.

5 Must Know Facts For Your Next Test

1. The placenta begins to form shortly after conception and is fully developed by around 12 weeks of pregnancy.
2. It contains specialized structures called villi that increase surface area for efficient nutrient and gas exchange.
3. The placenta acts as an endocrine organ, producing hormones like human chorionic gonadotropin (hCG) that are vital for maintaining pregnancy.
4. It provides immunological protection, helping to shield the developing fetus from certain pathogens while allowing some maternal antibodies to pass through.
5. At birth, the placenta is expelled from the mother's body in a process known as the afterbirth, typically within minutes after delivering the baby.

Review Questions

• How does the placenta function to support fetal development during pregnancy?
  • The placenta functions as a critical lifeline for the developing fetus by facilitating the exchange of nutrients and oxygen from the mother while also removing waste products. It has specialized structures called villi that increase its surface area, enhancing its ability to provide essential supplies for growth. Additionally, the placenta produces hormones that help maintain pregnancy and regulate physiological changes in the mother's body to support fetal health.
• Discuss the roles of hormones produced by the placenta and their significance in pregnancy.
  • The placenta produces several important hormones, such as human chorionic gonadotropin (hCG), progesterone, and estrogen. hCG helps maintain the corpus luteum during early pregnancy, preventing menstruation and supporting embryo implantation. Progesterone is crucial for maintaining a healthy uterine lining and reducing uterine contractions, which helps protect the fetus. Estrogen supports uterine growth and increases blood flow to ensure adequate nutrient delivery. Together, these hormones play vital roles in sustaining pregnancy and promoting fetal development.
• Evaluate how the structure and function of the placenta can impact prenatal health outcomes.
  • The structure and function of the placenta are pivotal to prenatal health outcomes. A well-functioning placenta ensures efficient nutrient transfer, oxygen delivery, and waste removal, all of which are crucial for optimal fetal growth. However, conditions such as placental abruption or placental insufficiency can compromise these functions, leading to adverse outcomes like low birth weight or preterm birth. Additionally, any disruption in hormone production can affect maternal health and fetal development. Therefore, monitoring placental health during pregnancy is essential for improving overall outcomes for both mother and child.

Related terms

Amniotic Sac:

A fluid-filled membrane that surrounds and protects the fetus during pregnancy, providing a cushioning environment for development.

Umbilical Cord:

A tube-like structure that connects the fetus to the placenta, allowing for the transport of nutrients and oxygen from the mother to the fetus and waste products from the fetus back to the mother.

Chorion: The outermost membrane surrounding the embryo, which contributes to the formation of the placenta and plays a role in nutrient exchange.