Study: IVF produces more boys than girls

Allison Sylte, KUSA
12:24 PM. MDT October 18, 2016

KUSA – A study conducted by the Colorado Center of Reproductive Medicine has found that in-vitro fertilization produces more boys than girls.

The study found that 55.3 percent of the babies born during in-vitro fertilization were male. By comparison, 51 percent of all the babies born naturally in the U.S. are boys.

For the study, CCRM researchers followed parents who underwent IVF. During the blastocyst stage, they say the embryos they examined were nearly equally divided between boys and girls.

But, when these embryos were transferred via IVF, that number skewed toward boys.

Researchers believe this ratio could be explained by impaired X-chromosome inactivation – something that only impacts female embryos.