Which hormone is crucial for maintaining pregnancy?

Progesterone plays a vital role in maintaining pregnancy. This hormone is essential for preparing the endometrium, or the lining of the uterus, to accept and support the implantation of a fertilized egg. Progesterone helps to maintain the uterine lining throughout the pregnancy, preventing it from shedding, which would result in a miscarriage. Additionally, progesterone helps to suppress maternal immune responses to ensure that the body does not reject the developing fetus.

While estrogen is also important in pregnancy, particularly for the development and function of various structures and in stimulating mammary gland development, its primary role is to support pregnancy rather than maintain it once established. Follicle-stimulating hormone and luteinizing hormone primarily focus on aiding in the process of ovulation and the menstrual cycle, rather than sustaining an existing pregnancy. Therefore, progesterone is recognized as the key hormone that ensures pregnancy is maintained.