Ovarian Stimulation Protocols for IVF

Women with low AMH or high FSH

In order to maximize success rates with in vitro fertilization we want a good number of high quality eggs from the woman. We generally want to get about 8-15 eggs at the egg retrieval procedure.

IVF success rates correlate with the number of eggs retrieved with IVF.

There are several ovarian stimulation medication protocols that are used to "pump up" the ovaries to make sufficient follicles and eggs. Without stimulating medications, the ovaries will only produce one follicle and mature egg per menstrual cycle (month).

All of the commonly used IVF regimens include injections of a medication containing follicle stimulating hormone - FSH. Injectable FSH products are sometimes referred to as "gonadotropins", or Human Menopausal Gonadotropins, HMG.

The woman is stimulated with the injectable FSH medications for about 8-12 days until multiple mature size follicles have developed.

What is the goal of a good IVF ovarian stimulation?

With ovarian stimulation for in vitro fertilization, the goal is to produce approximately 8 to 15 follicles that will give quality eggs at the egg retrieval procedure.

We do not want to have overstimulation of the ovaries which can lead to significant discomfort for the woman and in rare cases can result in ovarian hyperstimulation syndrome, OHSS.

We also do not want the ovarian stimulation to be insufficient and only give us a few eggs if we might have been able to obtain more by using higher medication doses, etc.

IVF can be successful with a very low number of eggs retrieved, but success rates are substantially higher when more than a few eggs are recovered.

With the ovarian stimulation, the job of the infertility specialist doctor is to:

• Select a proper medication protocol and dosing regimen
• Monitor the patient's stimulation progress so that medication doses can be adjusted properly

• Trigger with hCG at the ideal time. Triggering to early or too late reduces success and can sometimes increase the risk for ovaian hyperstimulation (if triggerred late).
  Most mature sized follicles (about 15-20 mm diameter) will give mature eggs at retrieval.

Quality control throughout the entire process is very important with in vitro fertilization. One of the ways that we have improved quality control in our program is by using highly specialized ultrasound equipment.

How is the monitoring of the IVF stimulation done?

We try to stimulate the woman to get at least 4 follicles with sizes of 14-20mm diameter. Ideally, there would be at least 8 follicles between 13-20 mm for IVF.

The goal is to get a good number (about 8-15) of quality eggs.

Blood hormone levels and developing follicle sizes are monitored.

Ultrasound is used to measure the follicles (discussed above on this page).

Estrogen hormone blood levels are important. Estrogen (actually estradiol) levels are usually under 60 pg/ml at cycle baseline and rise significantly as multiple follicles develop.

Peak estradiol levels in IVF at the time of HCG are usually between 1000 and 4000 pg/ml.

The stimulating process usually takes about 8-10 days.

Graph showing estrogen hormone levels during an IVF stimulation.

Estradiol starts low and rises to 1000 to 4000 pg/ml by the time of the HCG injection

The HCG injection is given when the estrogen level and the follicle measurements look best for successful IVF outcome. The HCG shot is needed to induce final egg maturation.

The egg retrieval is planned for 34-35 hours after HCG injection - shortly before the woman's body might start to release the eggs (ovulate).

How many follicles do you need in order to get pregnant with IVF?

Usually, it is not difficult to get enough follicles to develop. However, sometimes the response of the ovaries is poor - and a low number of growing follicles are seen. The ability of the ovaries to stimulate well and make numerous follicles can be predicted fairly well by an ultrasound test - the antral follicle count.

The minimum number of follicles needed to proceed with IVF treatment depends on several factors, including follicle sizes, age of the woman, results of previous IVF stimulations and the willingness of the couple (and the doctor) to proceed with egg retrieval when there will be a low number of eggs obtained.

In our experience, IVF success rates are very low with less than 3 mature follicles.

Some IVF doctors will say that you should have at least 5 follicles of 14mm or greater while others might do the egg retrieval with only one follicle.

Women that are more likely to be low responders to ovarian stimulation would be those that have low antral follicle counts, those women who are older than about 37, women with elevated FSH levels, and women with other signs of reduced ovarian reserve.