At the 15th week of pregnancy, the fetus is 13 weeks old, weighs about 50 grams and is 12 centimeters long. On ultrasound scans, the baby may be seen sucking its thumb, as this is how the baby is shaping its facial muscles to feed itself after birth.
Fetal development at 15 weeks
By Rebeca Reus BSc, MSc (embryologist), Zaira Salvador B.Sc., M.Sc. (embryologist) and Sandra Fernández B.A., M.A. (fertility counselor).
Last Update: 05/04/2022