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20 Weeks Post Ovulation - Second Trimester
Bone marrow starts making blood cells.

LENGTH: The crown-to-rump length 5.6 to 6.4 inches (14 to 16cm).

About 9 ounces (260g).

MOTHER"S SIZE: Uterus is about even with the bellybutton. Mother's growth up to this point may have been irregular but usually becomes more regular after the 20th week.

Head and Neck
Extremely rapid brain growth begins lasting until five years after birth. Eyebrows and scalp hair become more visible and fetus blinks more often. Lanugo hair covers body completely, although concentrated around head, neck and face.

Heart beat grows stronger.

Testes of male fetuses begin descending from the pelvis into the scrotum.

Legs approach final length and proportion relative to body. Arms and legs move with more force, as muscles strengthen. Skeleton hardens. Hand strength improves. Although the placenta provides nearly all fetal nourishment, fetus will begin to absorb small amounts of sugar from swallowed amniotic fluid. By 21 weeks, fetal bone marrow starts making blood cells — previously done by the liver and spleen.


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