At 8.5 weeks, the embryo now resembles a human. Facial features continue to develop, the beginnings of external genitalia form, the anal passage opens although the rectal membrane is intact, circulation through the umbilical cord is well developed, and long bones begin to form.
Review Date 9/26/2015
Updated by: Daniel N. Sacks MD, FACOG, pbstetrics & gynecology in private practice, West Palm Beach, FL. Review Provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.