Baby Chris is 17 Weeks Old

[This is part 18 of a multi-part series chronicling a pregnancy through the lens of “Baby Chris.” Click here for other parts.] 

Seventeen weeks after fertilization (19 weeks LMP), Baby Chris is about six inches long and weighs a bit more than half a pound—about the size of a tomato.

Photo by Melanie Brown on Unsplash

Hair growth begins around this time, and the eyebrows are complete. According to the Endowment for Human Development, “[a]ll skin layers and structures are present, including hair follicles and glands.”

Baby Chris has also developed vernix, “the waxy or cheese-like white substance found coating the skin of newborn human babies.” The exact function of vernix is unclear; the leading hypothesis is that it has something to do with protecting the baby’s skin from potentially damaging effects of amniotic fluid.

To learn more about prenatal development, download the free See Baby app wherever mobile apps are sold.