LONDON, Nov. 13 (UPI) -- Drugs used to improve fertility can result in human "chimeras," babies who are blends of two genetically distinct individuals.
Chimeras result when cells of two embryos fuse together and this possibility, though rare, is becoming more common as fertility drugs and techniques increase the rate of twinning, the London Telegraph reported.
The possibility that in-vitro fertilization is linked to chimerism was raised by a study of a chimera by David Bonthron of the University of Leeds.
"It was not the first to come to light, but it was the first related to IVF," he said.
He described one case of a chimeric IVF baby who resulted from the fusion of a male embryo and a female embryo. Though outwardly male, the left side of the child's body contained an ovary and fallopian tube.
