Popsugar Parenting Pregnancy How Big Is My Baby? A Week-by-Week Fetus-Size Guide Based on Objects You Actually Know 8 June 2018 by Annie Gabillet View On One Page Photo 10 of 36 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 10 Week 14: Credit Card Open your wallet, and you'll see a good approximation of how long your baby is: 3.42 inches. Previous Next Start Slideshow Pregnancy