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What is Spontaneous movements of fetus begins at and explain in detail?
12th Gestational Week The uterus usually is just palpable above the symphysis pubis, and the fetal crown-rump length is 6 to 7 cm. Centers of ossification have appeared in most fetal bones, and the fingers and toes have become differentiated. Skin and nails have developed, and scattered rudiments of hair appear. The external genitalia are beginning to show definitive signs of male or female gender. The fetus begins to make spontaneous movements.Reference: WIlliam's Obstetrics; 24th edition; Chapter 7; Embryogenesis and Fetal Morphological Development