Your Weekly Pregnancy Development: Week 10

Every minute, your baby's brain produces 250,000 new neurons

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Week 10

Little details and big developments

Week 10: All of your baby’s vital organs have formed

After weeks of life as an embryo, by the end of the 10th week of your pregnancy, your baby becomes a fetus.* Here are some of the other changes your baby is going through during your 10th week of pregnancy:

  • By the 10th week of pregnancy, your baby probably measures more than 1 inch, or roughly the length of a quarter.
  • By the end of the 1st trimester, your baby will grow to be about 3 inches — around the length of a kiwi fruit. This measurement doesn't even take into account arms and legs. That's because in the 1st trimester, your baby is measured from the top of the head to the bottom of the rump.
  • By the beginning of the 10th week of pregnancy, all of your baby's vital organs have formed.
  • His embryonic tail, located at the bottom of his spinal cord, has disappeared.
  • His bones continue to develop. On an ultrasound, your baby's bones appear white.
  • At 10 weeks pregnant, his ears get close to their final form.
  • His teeth buds emerge, and his eyelids develop further.
  • His testes start producing the male hormone testosterone around the 10th week of pregnancy.
  • Tiny fingers and toes are fully separated (no more webbing).
  • Plus, your baby's brain growth really takes off. Every minute, 250,000 new neurons (or first brain cells) are produced.


Week 10

Your Week 10 nutrition and health

Keep eating food from all five food groups

By choosing good foods from all of the food groups, you're nourishing your baby with a broad range of different nutrients.

For a 2,000-calorie level diet, the USDA recommends the following servings of the major food groups:

  • 6 ounces of breads and grains
  • 5-1/2 ounces of protein (meat and beans)
  • 3 cups of dairy products
  • 2 cups of fruit (fresh, frozen, or canned)
  • 2-1/2 cups of vegetables (fresh, frozen, or canned)

To determine your specific caloric needs, visit


Guiding the way

Hormones released by your placenta, ovaries, adrenal glands, and pituitary gland guide the growth of your baby as well as changes within the organs in your own body.

Keep learning about your baby's development every week
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