progesteroneproduces

Progesterone production refers to the synthesis and release of progesterone by endocrine glands, principally the ovarian corpus luteum and, during pregnancy, the placenta; the adrenal cortex also contributes small amounts. In humans, the steroid is produced from cholesterol through a two-step pathway: cholesterol is converted to pregnenolone by the mitochondrial enzyme P450scc (CYP11A1); pregnenolone is then converted to progesterone by 3β-hydroxysteroid dehydrogenase (3β-HSD).

In the ovary, luteinized theca and granulosa cells synthesize progesterone, especially after ovulation during the luteal phase. Luteinizing hormone stimulates these cells to drive progesterone production, which helps prepare and maintain the endometrium for potential implantation.

In pregnancy, the placenta becomes the main producer of progesterone. It expresses the necessary enzymes to convert pregnenolone to progesterone and relies on high activity of placental steroidogenesis, supported by maternal cholesterol and fetal contributions. Placental progesterone supports decidualization and helps suppress uterine contractions to sustain pregnancy.

Regulatory aspects: In the menstrual cycle, progesterone production rises after ovulation and falls if pregnancy does not occur. In early pregnancy, human chorionic gonadotropin (hCG) from the embryo rescues the corpus luteum to maintain progesterone output; later, placental production increases to sustain pregnancy. Adrenal production, regulated by adrenocorticotropic hormone (ACTH), provides smaller, more constant amounts of progesterone outside reproductive contexts.

Clinical relevance: Abnormal progesterone production can affect implantation and pregnancy maintenance. Progestins and other therapies are used in contraception, luteal-phase support, and the treatment of certain reproductive disorders.