What are the two main hormones involved in maintaining pregnancy?

The two main hormones involved in maintaining pregnancy are progesterone and estrogen.

Progesterone is critical because it prepares the endometrium (the lining of the uterus) to receive and sustain a fertilized egg. It helps maintain the uterine lining throughout pregnancy, preventing contractions that may lead to premature labor. Additionally, progesterone supports breast tissue development for lactation and helps modulate the immune response to protect the developing fetus.

Estrogen plays a fundamental role as well, particularly in the development of the fetus and the maintenance of the pregnancy. It contributes to uterine growth, enhances blood flow to the placenta, and helps regulate the production of other hormones essential for pregnancy. Estrogen also stimulates the development of mammary glands in preparation for breastfeeding.

Together, these hormones create an optimal environment for fetal growth and development, sustaining the pregnancy until delivery.