What is the primary function of estrogen during pregnancy, as explained by the nurse to a client?

Estrogen plays a crucial role during pregnancy, particularly in stimulating uterine and breast development. As pregnancy progresses, estrogen levels rise significantly, which contributes to several important physiological changes. One of the primary functions of estrogen is to promote the growth and development of the uterine muscles, allowing the uterus to expand and accommodate the growing fetus. Additionally, estrogen is vital for the development of the mammary glands in preparation for lactation. These processes are essential for supporting both fetal growth and ensuring that the mother can provide nourishment after delivery.

While aspects like fetal weight gain, preparation for delivery, and maternal appetite are influenced by various hormones and factors during pregnancy, the direct stimulation of uterine and breast tissue development is a primary and essential function of estrogen during this time.