Gonadotropin Stimulation Ceiling Effect Demonstrated
Number of 2PN embryos affects IVF outcomes differently in women under and over age 37
MONDAY, June 19 (HealthDay News) -- In women who undergo in vitro fertilization (IVF), the odds of achieving a successful clinical pregnancy increase until age 30 (odds ratio 1.72 per year) and then begin a linear decline, according to a study published in the June issue of Fertility and Sterility.
Danielle E. Lane, M.D., of the University of California San Francisco, and colleagues studied clinical pregnancy rates in 467 women who underwent a first fresh non-donor cycle of IVF.
In women under age 37, they saw maximal rates when 20 oocytes were retrieved (OR 1.03), five 2-pronuclei (2PN) embryos developed (OR 1.91), and no more than two embryos transfered (OR 0.72) for each additional embryo transferred. In women ages 37 and older, they saw maximal rates when 10 oocytes were retrieved (OR 1.09), 20 2PN embryos developed (OR 1.29), and no more than two embryos transfered (OR 0.72) for each additional embryo transferred.
"Future prospective studies should be conducted to determine whether the ceiling effect demonstrated here is due to oocyte quality or uterine receptivity," the authors conclude.