Research in my laboratory concerns the effects on fetal development of endogenous sex hormones, naturally occurring estrogenic chemicals in food, (such as phytoestrogens in soy), and estrogenic manmade chemicals in consumer products (such as bisphenol A in plastic). We collect fetal mouse reproductive tissues and use primary mouse and human cell culture to investigate cellular mechanisms that mediate responses to hormones and other chemicals. We have confirm observations from in vivo experiments using mice. An important aspect of this research is that we use a physiologically based approach to determine the doses of chemicals that we examine. This approach has led to findings that fetal tissues are extremely sensitive to much lower doses of endogenous estradiol and manmade estrogenic chemicals than had previously been appreciated.