Pregnancy is a time of great change for a woman's body. As the mom's uterus grows, the baby develop its bones, vital organs and senses. Understanding the stages of the baby's development can help her fully prepare for each stage of pregnancy.
First Trimester
While the mother is feeling sick and tired during the first trimester, which ends after the first 12 weeks of pregnancy, her baby's bones, sex organs, arms, legs, heart, brain, spinal cord and facial features are forming, according to FamilyDoctor.org. By the third month, her baby is 3½ inches long and weighs just more than 1 oz., according to the American Congress of Obstetricians and Gynecologists.
Second Trimester
During the second trimester, her baby's intestines form, his eyelids appear, hair grows, and the external sex organs develop. Also, by this time, the baby has developed sweat glands, fat and fingerprints. Additionally, during the second trimester, she may be able to feel her baby move for the first time. The second trimester lasts through the twenty-sixth week of pregnancy and near the end of this time, the baby will be about 14 inches long and weigh approximately 2¼ lbs. If her baby is born at this time, he could survive with the assistance of medical technology, according to the American Pregnancy Association.
Third Trimester
The third trimester ends when the baby is born, but begins at week 27. According to FamilyDoctor.org, during this time, the baby can hear and recognize the mother's voice and might move in response to music. He may begin using the senses of hearing and touch to learn about his own body and his mother's surrounding womb. The baby still can't see much, though. While his eyes can detect very bright light, it's too dark to see in the uterus.
The baby uses his sense of touch to practice important movements, including grasping and sucking, and he may start sucking on his thumb. He may weigh 6 to 9 lbs. or more and be between 19 and 21 inches long.
Also, the mother may begin to feel less fetal movement as she nears the delivery date, due to less available space in the uterus for a growing baby. FamilyDoctor.org recommends that she contact her health care provider if she doesn't feel the baby move 10 times during an hour or if she is concerned about the lack of movement.
References
- FamilyDoctor: Changes in Your Body During Pregnancy: First Trimester
- The American Congress of Obstetricians and Gynecologists: How Your Body Grows During Pregnancy
- American Pregnancy Association: Fetal Development: Second Trimester
- FamilyDoctor: Changes in Your Body During Pregnancy: Third Trimester
