Progesterone’s role in the ovulatory cycle is to help prepare and support the endometrium (lining of the uterus) to accept and nourish a developing embryo. Progesterone is initially produced by the leftover follicles on the ovaries, the corpus luteum, and later by the placenta.
When insufficient progesterone is produced it is sometimes called a luteal phase defect. Oftentimes, this condition is effectively treated with externally administered progesterone.
Women undergoing IVF cycles with Lupron, Antagon, of Cetrotide down regulation always receive supplemental progesterone. These drugs interfere with normal progesterone synthesis.
Human chorionic gonadotropin (hCG), Pregnyl, Ovidrel
hCG is known as the “pregnancy hormone” and rising levels indicate that a pregnancy has been established. hCG can also finally prepare the follicles for, and initiate ovulation. This is because the body responds to a spike in hCG levels in the same manner as the LH spike.
Pregnyl is a “human derived” product with some impurities. Ovidrel is produced in culture by mammalian cells that have been genetically engineered to produce pure hCG identical to the bodies.
hCG is administered to women undergoing FSH ovulation induction when the physician judges that the follicles are mature. In an IVF cycle, the hCG injection is given and egg retrieval is scheduled accordingly, usually 34-36 hours later. Similar protocols are followed for women undergoing stimulated IUI using great caution to help control possible high order (>3) multiple births.
Luveris is produced by genetically modified mammalian cultures and is identical to the body’s luteinizing hormone. It is indicated for stimulation of follicular development in infertile hypogonadotropic hypogonadal women with profound LH deficiency (LH < 1.2 IU/L). However, “off label” uses might be to finally prepare the follicles and initiate ovulation. Conceivably, Luveris could also be used to “sweeten” IVF drug stimulation protocols in some women.