What is the primary role of progesterone in early pregnancy?
Correct Answer: B
Rationale: The correct answer is B: To maintain the uterine lining for implantation and pregnancy. Progesterone is crucial in early pregnancy as it helps in thickening and maintaining the uterine lining to support implantation of the fertilized egg and sustain the pregnancy. It also plays a role in suppressing the immune response to prevent rejection of the embryo.
A: To stimulate fetal development - Incorrect. Progesterone primarily focuses on preparing the uterus for pregnancy rather than directly stimulating fetal development.
C: To trigger ovulation and release of the egg - Incorrect. Progesterone is involved in the second half of the menstrual cycle after ovulation has occurred and is not responsible for triggering ovulation.
D: To increase the production of amniotic fluid - Incorrect. Progesterone does not directly impact the production of amniotic fluid, which is mainly regulated by the fetal kidneys and placenta.