Sir

We wholeheartedly agree with your Editorial ”Reining in assisted reproduction“ (Nature 422, 647; 200310.1038/422647a) that more research is needed to identify and evaluate the risks that assisted reproduction may pose to children and their mothers.

In the United States, a ban on federal funding for embryo research makes this work especially difficult. Lifting this ban would both enable more outcome studies and ensure that research on new treatments would be subject to federal supervision and would be conducted in accordance with human-research subject protections under the common rule.

In the United Kingdom and other European countries, patients benefit from state-supported healthcare systems that subsidize and regulate the treatment for infertility and assisted-reproductive technologies. Unfortunately, most patients in the United States pay for their expensive treatments out of their own pockets. Sometimes, parents' desire to maximize their chances of having a baby and their interest in minimizing risk to themselves and their offspring are in conflict.

We have doubts as to whether a system analogous to the United Kingdom's Human Fertilisation and Embryology Authority is appropriate in the United States, where citizens fervently guard their rights to privacy and reproductive choice.

Many would see a government body with the power to dictate treatment choices as an unwarranted imposition and intrusion, especially because the government does not subsidize payment for their treatment.

Proactive, responsible self-regulation is the key to ensuring patient safety. The American Society for Reproductive Medicine (ASRM) guides medical practice and research and keeps members abreast of the ethical issues arising daily in reproductive medicine; the Society for Assisted Reproductive Technology (SART) sets the standards for assisted-reproductive technology clinics, including laboratory certification, reporting of clinic success rates and compliance with the ASRM guidelines. This voluntary yet effective procedure reflects the dedication of our members to assuring safety, efficacy and confidentiality for all our patients.

We hope that the US government will one day fund research in this field, with accompanying protection. In the meantime, we appreciate our international colleagues whose research informs our own work.