The problem was, with the focus on raising pregnancy rates and the simultaneous improvements in technique, the rate of multiple pregnancies as a result of IVF skyrocketed. Reproductive specialty organizations set standards for maximal embryo transfers. The efforts have paid off in terms of triplet and higher-order multiple births, but twin pregnancies continue to rise.
Fertility specialists still feel the tug between the need to control the multiple birth rate on one hand, and the principle of patient autonomy and free enterprise on the other, said Dr. Bradley J. Van Voorhis, who directs the IVF program at the University of Iowa Hospitals and Clinics in Iowa City.
To resolve this dilemma, many in the field are pinning their hopes on embryo selection – finding the healthiest, most viable embryos, those most likely to implant. “Without question,” said Dr. Rosenwaks, “identifying a viable embryo is one of the greatest challenges for IVF in the future.”
Dr. Robert G. Edwards in 1998 with 'test-tube babies' Jack and Sophie Emery.
Source ©AP Photo/Alastair Grant