FSH Levels under 15 still viable for ART/IVF

Women younger than 40 years old with basal follicle-stimulating hormone (FSH) levels between 10 and 15 IU/l produce oocytes with significant pregnancy potential, say researchers.

Elevated basal FSH levels are often used to predict poor assisted reproductive technology (ART) outcomes, but in their study of 191 ART cycles, Rieko Kojima (National Center for Child Health and Development, Tokyo, Japan) and colleagues found that women with FSH levels of up to 15 IU/l could still expect good outcomes.

Significantly more oocytes were retrieved in women with FSH levels below 10 IU/l than in those with levels between 10 and 15 IU/l, at 8.7 versus 5.5. But they had similar numbers of fertilized oocytes (4.6 and 4.0, respectively) and pregnancy rates per embryo transfer (31.3 and 38.1 percent, respectively).

The rates for women with FSH levels of at least 15 IU/l tended to be lower than those for the other two groups, at 2.2 retrieved oocytes, 1.4 fertilized oocytes, and pregnancy rate per embryo transfer of 10.0 percent, but the differences were not significant.

The researchers note that women with the highest FSH levels needed significantly longer ovarian stimulation and at higher doses than women with lower levels. They therefore suggest that "the basal FSH level reflects the ovarian response to gonadotropin stimulation, rather than pregnancy potential for each oocyte."