Others support helping HIV discordant couples have children with their own eggs and sperm through in vitro techniques—at least couples in which the man is HIV positive and the woman negative. They cite the 300 children already born to such couples with help from assisted reproductive technologies: neither children nor their mothers have become HIV positive.

Risk to offspring is paramount and may include long term effects of zidovudine and other antiviral treatments whose safety is questionable. Zidovudine does have a record of harming fetuses, but denying fertility treatment on this basis alone would be unjust as many women may have diseases requiring treatment throughout pregnancy—like epilepsy—for which there are no safety data. In fact most drugs have never been evaluated in pregnancy. However, zidovudine integrates into the host genome, with possible but unknown implications for the child and scope for heritable germline alterations, which are concerns.

HIV discordant couples are different from couples who are affected by other terminal illnesses or genetic conditions because of the added risks of infecting the woman and the child and the wider potential public health risk to healthcare workers and other patients undergoing fertility treatment.

On balance, though, offering assisted conception to these couples contravenes no ethical principles and seems to do more good than harm. Arguably, denying treatment might raise the potential for harm—from unprotected sex—but situations of particular risk—say of involving a surrogate mother—justify careful scrutiny and maybe denial.