Infertility comes in all shapes and sizes. From the 18-year old woman with Turner's Syndrome whose ovaries aged too quickly to the 35-year old woman with breast cancer whose chemoradiation made her infertile, there is no one, unified descriptor. Because of this, it is extremely difficult to predict who exactly is at risk for infertility.
That said, researchers at UC San Francisco are beginning to look at a wealth of these risk factors--from possible environmental exposures to baseline ethnic differences.
In a recent article in Reproductive Bio Medicine Online, they found that Asian-American women might actually have fewer pregnancies following intrauterine insemination (IUI) than their Caucasian counterparts.
The study followed up on a prior study by the same group of researchers that showed Asian-American woman had almost one-third fewer pregnancies and live births after in-vitro fertilization (IVF) as well (the more complicated procedure of the two).
What's interesting about these findings is that in both studies, researchers accounted for differences in age and other baseline characteristics among women, and also for the fact that the Asian-American women seemed to undergo longer periods of infertility before seeking treatment from a physician.
While the differences in outcomes are clear, the reasons behind them are not.
The group lists several hypotheses in their paper, including possible differences in environmental exposures (although this may be more difficult to believe if all women--Caucasian and Asian-American--were sampled from the same city); differences in herbs, supplements and other home remedies women may have tried before coming to the infertility clinic; and basic (yet probably not yet understood) differences in biology between two different ethnic groups.
The problem with this last idea (and the researchers point this out as well) is that "Asian-American" covers a lot of different ethnicities. Perhaps the lower fertility rates are seen only in certain sub-types of Asian women instead.