Fertility Drugs- Progesterone
Fertility Drugs – Progesterone for Endometrial Support
After ovulation, the ovaries produce progesterone. Progesterone is a hormone that prepares the endometrium (the uterine lining) for the fertilized egg as it arrives from the fallopian tube. If the ovary fails to produce enough progesterone, infertility or early pregnancy loss may result. This condition is known as luteal phase defect. There are two possible treatments for luteal phase defect - clomiphene citrate (or gonadotropins) and progesterone.
Progesterone may be administered by daily injection, vaginal suppositories, or in pill form. Treatment is begun 3-4 days after ovulation. It is very important to begin treatment at the right time. If progesterone treatment is started prior to ovulation it may actually interfere with the chance for conception. If progesterone treatment is started more than 4 or 5 days after ovulation it may not be effective.
A clear rise in the basal body temperature graph and/or change in the ovulation predictor kit will help pinpoint the time of ovulation. Treatment should begin 3 or 4 days after ovulation kit change or 2-3 days after the temperature is clearly "up".
After progesterone therapy begins, the temperature will be high - due to the medication. Progesterone is continued for about 2 weeks. If the menstrual period begins, the progesterone treatment is stopped and the next cycle begins. If the menstrual period is more than 3 or 4 days late, take a home urine pregnancy test. If the home pregnancy test is negative then stop the progesterone and your menses should begin in a few days.
If you conceive while using progesterone suppositories, it is generally recommended to continue treatment through the first 10 weeks of pregnancy. Low levels of progesterone can cause early pregnancy loss during that time. After 10 weeks the placenta takes over progesterone production.
The only recognized risk of this form of treatment is a theoretical one. Other forms of progesterone have been associated with congenital anomalies of babies exposed to the drug during the first 10 weeks of pregnancy. These "other forms" are different from the progesterone prescribed for infertility treatment.
There is no clear evidence that the progesterone used for infertility treatment causes congenital anomalies in offspring. We acknowledge a theoretical risk of major organ anomalies with this form of therapy. Progesterone has been used to support pregnancies for decades and is a common therapy.