Progesterone Test for Fertility - Progesterone Serum Test

A serum progesterone test measures the level of this key female steroid hormone, primarily produced by the corpus luteum in the ovary after ovulation and, during pregnancy, by the placenta. Its main function is to prepare the uterine lining (thickening and vascularizing it) for implantation of the fertilized egg and to maintain pregnancy by inhibiting uterine contractions. It is mainly used to assess ovulation, evaluate the efficiency of the luteal phase (the post-ovulatory phase), and monitor early pregnancy.