It was concluded that prenatal exposure to MDMA causes only subtle behavioral changes in developing rats, while the dams are at risk for the characteristic spectra of serotonergic changes. I have cited this study to several women who contacted me concerning their use of MDMA while pregnant. Ecstasy users are very frequently poly-drug users. This seems surprising to me. People who attend raves often engage in vigorous exercise and get quite hot, often without sufficient hydration.
Diets are often poor.
You mentioned that the evidence for birth defects from amphetamine and related compounds has produced conflicting results. MDMA is chemically similar to mescaline, the active ingredient in peyote cactus, which Native Americans have been using for thousands of years. The use of peyote by pregnant women is not uncommon, and no reports from a link between peyote and birth defects has been reported, though no systemmatic study has been conducted of which I am aware. I presume only slightly since every drug is unique. Thank you in advance for any time you can spare to respond to these questions.