It was a first for the entire world: Using a controversial in vitro fertilization technique, doctors in Kiev, Ukraine, helped a previously infertile couple conceive and deliver a baby girl. Some critics say, for genetic reasons, the use of this IVF method should have been restricted to producing a baby boy.

The baby was born on January 5, the result of an experimental technique known as “pronuclear transfer” and sometimes referred to as three-parent IVF