One of the most common birth defects is the neural tube defect (NTD), which affects 1 in 1,000 births. Very early in a pregnancy, usually by the second week, specialized cells begin the fusing procedure. This is gastrulation, and cells on the dorsal side of the fetus begin to fuse and form a neural tube. If the neural tube does not close completely, you get NTD.
A recommended safety precaution is for all women of childbearing age to take folic acid, even those not trying to get pregnant.
Types of Neural Tube Defects
There are two types of NTDs: open and closed. Open is more common, and NTDs occur when the brain or spinal cord is exposed at birth through a defect in the skull or backbones vertebrae.
Open NTDs
Some common open NTDs are spina bifida, anencephaly, hydranencephaly and iniencephaly.
Spina Bifida
In spina bifida, the fetal spinal column doesn’t close completely during the first month of pregnancy. There is usually nerve damage that causes at least some paralysis of the legs.
Anencephaly
In anencephaly, much of the brain does not develop. Babies with anencephaly are either stillborn or die shortly after birth.
Hydranencephaly
In this defect, the cerebral hemispheres are missing and instead filled with sacs of cerebrospinal fluid.
Iniencephaly
This is a rare neural tube defect that results in extreme bending of the head to the spine. Usually the neck is absent. The skin of the face connects directly to the chest and the scalp connects to the upper back. The infant usually will not survive more than a few hours.
Closed NTDs
The closed, and rarer types of NTDs occur when the skin covers the spinal defect. Common examples include lipomyelomeningocele where fatty tissue sticks to the spinal cord, lipomeningocel and tethered cord.
The Development of the neural tube
The embryo’s precursor to the central nervous system is the neural tube. The neural groove gradually deepens as the neural folds become elevated, and when those folds meet and coalesce in the middle line they convert the groove into a closed tube that is called the neural tube or neural canal. The center of the neural tube and the ectodermal wall forms the rudiment of the nervous system.
The neural tube develops in the first four weeks of pregnancy, often before many women even know they are pregnant.
Pre-Birth Prevention Treatment
Taking Folic acid is a recommended treatment. It is a form of vitamin B, which when taken before and during pregnancy prevents most neural tube defects.
Where do you get folic acid? Foods that include leafy green vegetables, peas, fruits, dried beans and nuts contain folic acid. Otherwise, grain products like enriched breads and cereals also contain folic acid.
Post Birth Treatments
Treatments vary depending on the type of neural tube defect. For instance, some mild versions of spina bifida need minimal treatment, but other forms require surgery to correct the problems.
Physical therapy may help children learn to walk with or without leg braces or other assistive devices.