A new study has found that genistein, a component of soy, disrupts ovary development in newborn female mice, adding to the growing body of literature pointing to potentially adverse effects of genistein on the reproductive system (Jefferson W et al. Biol Reprod. 2006;74:161-168).
In this study, conducted by researchers at the National Institute of Environmental Health Sciences in collaboration with an investigator at Syracuse University, in New York, female mice were injected with 50 mg/kg of genistein per day (comparable with what human infants might receive in a soy-based formula). Injections were made during the first 5 days of life, and the effects were observed on days 2 through 6.
Hampton T. Soy and Fertility. JAMA. 2006;295(8):880. doi:10.1001/jama.295.8.880-d