https://www.metaculus.com/notebooks/9247/polygenic-selection-of-embryos/

In vitro fertilization (IVF) is a fertilization procedure in which ova are removed from a woman and combined with sperm in a laboratory culture, with the resulting embryo then implanted in the woman’s or a surrogate mother's uterus. This assistive reproductive technology has been used successfully since 1978, and its use has increased over time, owing in part to women choosing to bear children later in their lives.

Often, combining sperm with extracted ova results in multiple viable embryos. For many years, doctors have been able to perform diagnostic screening tests to check the embryos for chromosomal abnormalities like Down syndrome and gene defects like Tay-Sachs, allowing them to select and implant the healthiest embryo.