The development of the spine begins in the womb, but continues after birth. As a baby grows and develops, he will slowly develop the characteristic S-shaped spine that adults have. Diet in the womb and positioning of the baby after birth can affect spinal development.
In the womb, spinal development begins with an embryonic structure called the neural tube. This tube eventually becomes the brain and spinal cord. In the first weeks of pregnancy, the tube elongates and folds inward. By about 28 days after conception, it is normally closed off. After about eight weeks of development, most organs are finished forming, but the brain and spinal cord continue to change and become more specialized up through birth and beyond as the bones of the spine form around the developing spinal cord.
After a baby is born, the spinal cord and vertebrae of the spine are all present, but still have some development to do. The spine after birth has only one curve instead of the three present in adults. This primary curve causes the spine to assume a C shape. When the baby begins lifting his head, the first secondary curve forms in the cervical vertebrae, the spinal bones of the neck. The second secondary curve forms as an arch in the lower back when the infant begins to crawl.
During fetal development, if the neural tube fails to close at the bottom near the lower back, a birth defect called spina bifida develops. In spina bifida, the spinal cord may poke through the bones of the spine. According to the March of Dimes, about 1,500 babies are born with spina bifida every year.
Prenatal vitamins are essential to proper development of the fetal spine. Folic acid, also known as folate, is especially important for neural tube development during the first few weeks of pregnancy before most women are aware that they are pregnant. Babies should be given tummy time, time spent lying prone, in order to allow them to develop the muscles needed to support the development of the spinal curves that will eventually allow them to crawl and walk.
Keeping a baby in an unnatural curved position for long periods of time might prevent or delay the proper development of the spine. Devices such as car seats, infant carriers and baby swings should only be used for short periods of time. Keeping a baby lying on his back most of the time or using upright carriers that do not support the legs and spine might also be damaging to spinal development.