During the fourth month of pregnancy, embryo development continues. Fetal weight increases considerably—from 16 g to 100 g. As for the length, a major change occurs, too: it grows from 8 cm to 18 cm.
By Elena Izquierdo Trechera M.D., M.Sc. (gynecologist), Rebeca Reus BSc, MSc (embryologist) and Sandra Fernández B.A., M.A. (fertility counselor).
Last Update: 11/14/2018