Spina Bifida

Tests for spina bifida done before birth

During your second trimester, you can have a blood test called the Reference maternal serum triple or quadruple screen to see whether you have a higher-than-normal chance of having a baby with birth defects. This test is used to screen a fetus for certain abnormalities, including Reference neural tube defects Opens New Window. The most common type of neural tube defect is spina bifida. The triple or quadruple screen test does not pose any risk to the fetus.

Opens New Window Pregnancy: Should I Have the Maternal Serum Triple or Quadruple Test? Opens New Window

If the triple or quadruple screen test shows that you have elevated levels of alpha-fetoprotein (AFP), a neural tube defect in the fetus, such as spina bifida, may be suspected. In this case, the following tests usually are done:

• High-resolution Reference fetal ultrasound Opens New Window. This test can help a doctor identify severe cases of spina bifida in a fetus, such as Reference myelomeningocele Opens New Window Reference Opens New Window, in which tissues and nerves are exposed and protrude from the spinal cord. Fetal ultrasound does not always detect abnormalities related to spina bifida, especially in mild cases.
• Reference Amniocentesis. This test usually is done to confirm elevated AFP levels identified by the triple screen test. It also is used to measure levels of acetylcholinesterase (ACH), an enzyme that is found in fetuses that have neural tube defects. You may have amniocentesis without first having an ultrasound or even when an ultrasound appears normal.

Severe spina bifida is strongly suspected when amniocentesis shows high levels of AFP and ACH and when fetal ultrasound results show severe spinal abnormalities.

An early diagnosis of severe spina bifida allows you to make an informed decision about your pregnancy. If you decide to carry the fetus to term, knowing about the defect can help you and your family prepare for your baby's special needs.

Testing for spina bifida after birth

Children who have mild spina bifida may have no physical symptoms. It is often not found until later in life, when the person has a back Reference X-ray Opens New Window for other reasons. It usually does not cause any problems.

Severe spina bifida is usually obvious at birth, because the baby has a noticeable swelling on the back. Many babies with severe spina bifida, especially those with myelomeningocele, have enlarged heads caused by an excess of spinal fluid in the head (Reference hydrocephalus Opens New Window).

After birth, tests to evaluate the extent of the spinal defect may include:

• Reference MRI, which gives a detailed picture of the brain, spinal cord, and related nerves.
• Reference CT scan, in which an X-ray machine rotates around the body to produce a three-dimensional view. This allows a doctor to see deformities or swelling in the brain and spinal cord.

Spina bifida often results in severe curvature of the spine—Reference scoliosis Opens New Window, kyphosis (hunchback), or both. Periodic physical exams of the Reference spine Opens New Window Reference Opens New Window usually are recommended.

Babies with severe spina bifida often have problems related to nerve damage of the spinal cord. This nearly always affects the Reference urinary system Opens New Window Reference Opens New Window. Evaluation to determine the extent of this damage may include a Reference renal ultrasound and Reference cystourethrogram.

Nerve damage may also affect the limbs, especially the legs. During your child's physical exams, the doctor will look for limb deformities, such as Reference clubfoot Opens New Window Reference Opens New Window. The doctor will also observe your child's arm and leg movements.

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.