Jacquelynn Kerubo made a big decision right before New York City went into lockdown: to transfer a "mosaic" embryo into her uterus. As she explains in an essay for the New York Times, "mosaic" has been used since 2015 to describe the roughly 20% of IVF embryos that genetic testing shows are neither normal nor abnormal but somewhere in between. Kerubo knew her embryo's classification because she and her husband had finished two rounds of in vitro fertilization in their quest to have a child. Of the five embryos that resulted, four were abnormal. The fifth had an extra 22nd chromosome on a few cells, making it a "low-level mosaic embryo." But there was no certainty of outcome contained within that determination.
A resulting pregnancy involving it could lead to miscarriage, a healthy and typical baby, or disabilities ranging from congenital heart defects to "asymmetrical development (meaning one side of her body could look like it was melting while the opposite side looked normal). ... It was like rolling the dice, except for someone you’ve never met." They decided to roll it, and have the embryo implanted, which they did after one stumbling block in which one doctor refused to carry out the procedure because of the mosaic classification. Kerubo is currently pregnant. "The last time I glimpsed her full profile, at five months gestation, her nose, long and sharp, was prominent and unmistakable," Kerubo writes. "I wondered if it was one of the characteristics of the extra 22nd chromosome or if she’d simply inherited my husband’s nose." (Read her full essay, which touches on the shortcomings of genetics testing on IVF embryos, here.)