Detection in Pregnancy

Spina bifida is usually detected in pregnancy by a detailed fetal ultrasound, or by an Alpha-fetoprotein (AFP) test.  Abnormally high levels of AFP can indicate there is a neural tube defect.  Typical babies only excrete AFP into the amniotic fluid through their urine.  A baby that has an open spine will also release AFP through the opening in its body- thus increasing the AFP levels in the amniotic fluid.  However, there are other reasons that AFP levels can be higher than expected, so the test should be viewed as an indicator, not a diagnosis.

Prenatal Care

One it has been determined you are carrying an infant with spina bifida, you will be considered a “high risk” pregnancy and your health and the health of the infant will be monitored more closely.  You will usually be assigned to a doctor that specializes in high risk pregnancy and you will receive more detailed and more frequent ultrasounds.  A c-section will be planned, to lessen trauma on the baby’s spine and to ensure the head does not become stuck in the birth canal.  At least eighty percent of children with spina bifida also have hydrocephalus and will need to have a shunt placed shortly after birth.  Although the shunt usually works properly and drains away the excess fluid, it is not unusual for the infant to have a larger than average head circumference.   Some women decide to participate in the MOMS study – a clinical trial that compares how babies who have prenatal surgery do compared to those who have postnatal surgery.  If you are in the MOMS trial, your baby may have the opportunity to have surgery before birth.

Incidence and Risk Factors

Ninety-five percent of all spina bifida pregnancies occur in women who have no history of this defect in their family.  Some women are at higher risk than others, including those who:  had a previous pregnancy affected with a neural tube defect, has diabetes, is obese, is of lower socioeconomic status, was exposed to high temperatures early in pregnancy, uses certain seizure medications, or is white or Hispanic.  Taking folic acid before and during pregnancy can help prevent spina bifida because lower levels of folic acid are found to correlate strongly with incidence of spina bifida.

In the United States, spina bifida occurs in about 7 out of every 10,000 live births.  It is estimated there are about 70,000 people with spina bifida living in the United States today.  There are three types of spina bifida.  In spina bifida occulta, there is no opening on the back, but the vertebrae aren’t completely closed.  There is usually no nerve damage, and some people don’t even know they have it.  However, there can be some hair or a dimple at the site, and some people may develop problems later on.  Meningocele is the least common form of spina bifida.  In meningocele, the meninges are damaged and protrude through the spinal column.  It appears as a fluid filled sac on the back.  There is usually no nerve damage since the sac is only full of cerebrospinal fluid (CSF).  Myelomeningocele is what we typically think of as spina bifida.  The vertebrae do not completely close during development and the spinal cord and meninges also develop abnormally, extending out through an opening on the back.  There is usually a sac of CSF around the spinal cord, and there is almost always some type of nerve damage.

ultrasound.jpgWhat to Expect

A child with spina bifida may experience paralysis, loss of sensation, and or loss of bowel and bladder control.  The lower the lesion, the more function the child usually has.  Many children with spina bifida also have hydrocephalus or excess fluid in the brain.  A shunt can be placed to drain the fluid out of the brain and into the abdominal cavity or underneath the skin, where it is absorbed by the body and eliminated in the urine.  Arnold Chiari Malformation also occurs frequently in children with spina bifida.  In this condition the cerebellum (the back part of the brain) extends down into the spinal canal.  The brain puts pressure on the spinal cord and can block the flow of CSF in the spinal cord.  Problems with sleep, breathing, and swallowing are also associated with Chiari Malformation, and surgery is often necessary to alleviate the pressure.  Club feet are also common with spina bifida and they need to be corrected through splints, bracing, and surgery.  Children with spina bifida are also at higher risk for vision problems, so vision is often tested within the first year.  Seizures and other problems with brain function are not uncommon.  The kidneys will also have to be checked to make sure urine does not reflux up into them, and the bladder will be tested to see how much pressure it can hold.  Many infants with spina bifida need to be catheterized to avoid damage to the bladder and kidneys, and they may need some type of bowel program to keep them from being constipated.  The lack of tone in the lower part of the body can also make children with spina bifida more prone to rectal prolapse, a condition where the rectum starts prolapsing and sticking out of the body.  In extreme cases rectal prolapse is corrected with surgery to pull the rectum back up and tack it inside the body.

In the NICU

A newborn with spina bifida can expect to undergo surgery within the first couple days of life.  The lesion on the back will be closed, and if necessary, a shunt will be placed to control hydrocephalus.  It is not uncommon for infants with clubbed feet to receive their first splints while still in the neonatal intensive care unit (NICU).  Infants usually have to stay in the NICU for a week to 10 days, but may have to stay longer.  Often when newborns are brought home, they are transported in a special car seat that allows them to lie down.  This decreases pressure on the surgical sites.

Going Home

Once home, you should care for your infant just as you would a typical infant, but be alert to any symptoms you may see that could indicate shunt malfunction or infection of the surgical sites.  Feeding may also be an issue since children with spina bifida may have trouble sucking and swallowing.  Feeding obstacles can often be overcome with speech therapy.  Infants may also have a high pitched, squeaky cry called stridor and they may have little or no muscle tone in certain parts of their body.  Lack of sensation in the lower extremities can cause many babies to scrape up their feet and legs on the floor without realizing it.  Understand that many milestones may be delayed, but with hard work and therapy, most children with spina bifida can expect to live a normal life with the assistance of mobility devices (such as wheelchairs and braces) and a good bowel and bladder program.

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