What is the main purpose of estrogen during pregnancy?

The main purpose of estrogen during pregnancy is to support the development of the uterine lining. Estrogen plays a crucial role in preparing the uterus to be a suitable environment for the developing fetus. It stimulates the growth of the endometrial tissue, which becomes essential for implantation and nourishment of the embryo. As the pregnancy progresses, estrogen levels rise significantly, further thickening the uterine lining and facilitating the necessary adaptations in blood supply and nutrient delivery to sustain the developing fetus.

While it is true that estrogen also contributes to other functions during pregnancy, such as influencing labor and supporting some aspects of ovarian function, its primary role is the enhancement of the uterine lining. This preparation is vital for the successful implantation of the fertilized egg and the maintenance of the pregnancy. The uterine lining must be adequately prepared to support the growing placenta and fetal development, making the role of estrogen critical in this early phase of pregnancy.