"Dose calculator" of FSH for IVF treatments

Jul 16, 2007 12:42 GMT  ·  By

We are a unique gene complex, so, if we function so differently from one individual to another, why not use a personalized IVF (in vitro fertilization)? Especially as 90 % of the women receive the wrong dose when undergoing IVF.

An international team has developed an easy-to-use mathematical formula that permits a personalized approach to ovarian stimulation therapy for women involved in IVF programs. When clinicians employed the algorithm to measure the best starting dose of FSH (follicle stimulating hormone) for each patient, both the number of retrieved oocytes and pregnancy levels increased.

The new formula is based on four factors assessed routinely in women evaluated for IVF: normal (or basal) levels of FSH, body mass index, age and the number of small growing follicles in the ovary detected by screen images.

"This FSH dose algorithm is simple and easy to use and utilizes readily available patient characteristics. It is the first to be tested in a prospective multi-national clinical study and it provided each patient with an individualized starting dose of FSH, which could be maintained throughout treatment and resulted in an excellent treatment outcome as testified by the number of oocytes retrieved and the high pregnancy rates", said Professor Fran?ois Olivennes, coordinator of the Centre de FIV Eylau La Muette, Paris, France.

"This approach should enable us to improve patient management, treatment outcomes and safety by reducing the chances of having to either cancel cycles because the ovaries have not been stimulated enough or of ovarian hyperstimulation syndrome (OHSS) developing because the ovaries have been over-stimulated."

OHSS can take place in 3-8% of IVF treatments. Moderate cases induce nausea and vomiting. Severe OHSS can provoke ovarian enlargement and fluid imbalances, inducing thrombosis and, very rarely, death.

The international group treated 161 IVF patients, younger than 35, in 18 centers around the world and found that 75 % of them should receive a lower drug amount than they would usually receive, while 15 % should get a higher dose.

They received one of five different doses of FSH, measured in international units (IU) of 75, 112.5, 150, 187.5 and 225 for 11 days. Oocytes were collected from 84.4% of women, and 80.9% of the women subsequently underwent embryo transfer. Pregnancies per cycle were 31.3%, 31.1%, 35.3%, 50% and 20% per each category of starting dose, with an overall of 34.2%.

Two cases of severe OHSS were linked to pregnancy. "We still have more work to do before the algorithm can be used for all patients in the clinic. We have demonstrated its usefulness in women younger than 35 undergoing IVF; further work is required to extend its use in other patient groups."

"At present, reproductive medicine specialists determine starting doses so as to induce multiple follicle development based upon some of the characteristics used to develop our model, other tests of ovarian reserve, and their previous clinical experience. We hope that this research will represent a move towards an evidence-based approach to the use of FSH."