What exactly does Crinone do? I am in my fourth month of IUI. I was on Gonal-F and then Profasi, and I now am on Crinone for 12 days. Does Crinone completely stop you from menstruating? Or, if I haven't yet menstruated, could that mean I'm pregnant?

Benny

Many physicians choose to use one or another form of progesterone after ovulation to "support the luteal phase." Unfortunately, there is no evidence at all to suggest that this approach is of any benefit. The only group of patients who seem to benefit from progesterone administration are those who have been pretreated with a GnRH-agonist such as Lupron or Synarel before ovulation induction or IVF. There are no studies suggesting other women benefit at all.

Progesterone has traditionally been administered as an injection. Alternatives include vaginal/rectal suppositories, oral tablets, oral progesterone lozenges or vaginal creams. Crinone is a vaginal cream. It is quite expensive compared to the other alternatives. When I find progesterone support is needed, I prescribe a combination of progesterone lozenges that dissolve in the mouth and suppositories at bedtime. I have not yet been convinced that Crinone offers a significant advantage over this approach, which is about one-tenth the cost of using Crinone.

As to your delayed period, the use of progesterone supplementation does frequently delay the onset of the upcoming menstrual period. Unfortunately, this side effect is not predictable and varies from cycle to cycle.