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Pregnancy and Fetal Development

Picture of Second Trimester (16 Weeks)

Picture of Second Trimester (16 Weeks)

This photo shows a baby at 16 weeks of gestation during the second trimester of pregnancy. At this stage:

  • Tissues including bones and muscles continue to form.
  • The baby begins to develop translucent skin.
  • The baby begins to form a substance called meconium, which is the first bowel movement.
  • The baby displays a sucking reflex with the mouth.
  • The baby weighs approximately 3 ounces and is between 4 to 5 inches in length at this time.
Image Source: Nestle / Petit Format / Photo Researchers, Inc.

Text Reference: American Pregnancy Association: "Fetal Development: Second Trimester"