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 12 of 36 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 12 Week 16: a Can of Coke While not the healthiest part of a pregnancy diet, a can of Coke is about the same size as your fetus, 4.57 inches. Previous Next Start Slideshow Pregnancy