The Heart Begins Beating

6½ weeks pregnant (since Last Menstrual Period) (4½ weeks since fertilization)

Close-up of Beating Heart

7½ weeks pregnant (since Last Menstrual Period) (5½ weeks since fertilization)

Brains and Beauty

8½ weeks pregnant (since Last Menstrual Period) (6½ weeks since fertilization)

The Prenatal Eye

9½ weeks pregnant (since Last Menstrual Period) (7½ weeks since fertilization)

Jaw Movement

10 weeks pregnant (since Last Menstrual Period) (8 weeks since fertilization)

The Fetal Period

11 weeks pregnant (since Last Menstrual Period) (9 weeks since fertilization)

Exercising

12 weeks pregnant (since Last Menstrual Period) (10 weeks since fertilization)

Maturing Nose and Lips

13 weeks pregnant (since Last Menstrual Period) (11 weeks since fertilization)

Mouth and Tongue

14 weeks pregnant (since Last Menstrual Period) (12 weeks since fertilization)

Hormonal Stress Response

18 weeks pregnant (since Last Menstrual Period) (16 weeks since fertilization)

Holding the Cord

22 weeks pregnant (since Last Menstrual Period) (20 weeks since fertilization)

Eyes Open and Close

26 weeks pregnant (since Last Menstrual Period) (24 weeks since fertilization)

The Big Yawn

30 weeks pregnant (since Last Menstrual Period) (28 weeks since fertilization)

Exercising the Tongue

34 weeks pregnant (since Last Menstrual Period) (32 weeks since fertilization)