Minimal stimulation IVF requires alternative protocols to traditional IVF using less medication and may be appropriate for certain patients.
In vitro fertilization (IVF) is typically a two month process for most couples. In order to achieve a good cohort of synchronously developing eggs, birth control pills are commonly used in the month prior to stimulation of the ovaries with gonadotropin medications. This has been shown to maximize the number of good quality eggs and thus pregnancy rates for most patients. However, there are alternative protocols using less medication for principally two groups of patients.
The first group includes women who have normal ovarian function who wish to take less medication and do not wish to have a large number of eggs retrieved on a given cycle. In this group, no birth control pills are given and the gonadotropin medications are started later than usual in the cycle. Ovulation is prevented with the use of a GnRH antagonist. Both medications are given as daily injections, with total number of days being less than in conventional IVF. Thus there are fewer days of monitoring (ultrasounds and blood tests) required. Risk of hyperstimulation is also lower. There are generally fewer eggs retrieved, which is the goal of this protocol. Egg and embryo quality are usually very good. With fewer embryos available to choose from for transfer, pregnancy rates are lower than with standard IVF. However, for women who wish to take less medication per cycle and who wish to have fewer eggs retrieved and who may be willing to do several IVF cycles to achieve a pregnancy, this protocol offers this opportunity. This type of protocol is not considered appropriate for couples who require intracytoplasmic sperm injection (ICSI) as more mature eggs are needed for that type of cycle.
The second group consists of women who are low-resonders to medication. They usually have few antral (resting) follicles in their ovaries and may have high basal FSH levels. Medication protocols for these women consist of Clomiphene citrate for 5 days, followed by low dose gonadotropins for approximately 5 days, along with a GnRH antagonist to prevent ovulation. Generally 3 to 4 mature eggs are retrieved, which is a similar number to a high dose medication regimen in these women; however, the patient has to be prepared for cancellation of the cycle if no mature follicles develop. Less frequent monitoring is required (usually two to three ultrasounds and blood tests) as compared to a higher dose protocol. If two embryos are available for transfer, pregnancy rates have been shown to equal those of higher dose stimulation protocols in these women.
Both of these protocols are offered at Northern California IVF Fertility Center, for those couples that wish a minimal stimulation protocol and who medically are good candidates for these.