One of the difficulties in obtaining an answer to this important question is that it is difficult to obtain information (data) from a large enough study population to be able to come to a firm conclusion. Most studies have involved a small number of subjects or persons in a special situation, thus raising questions about being able to relate the data to the general population. Dr. Judith K. Grether and her colleagues address this issue. They were able to study the hospital and medical records of a large number of very premature, low birth weight infants who by age 2 demonstrated spastic Cerebral Palsy; they compared them to similar low birth weight and premature infants who did not demonstrate Cerebral Palsy by age 2. The study included patients from hospitals in the San Francisco Bay area of California.

This study population was chosen from (a) 1978 first born children, (b) who had gestational age less than 32 weeks and birth weights less than 1999 g. (4.4 lbs.) and (c) who were exposed to intrauterine infection. 170 children with spastic CP and 270 without neurological damage (controls) were selected as study subjects. Among children with CP, 54% had spastic diplegia (both lower limbs), 26% has spastic quadriplegia (both upper and lower limbs), 17% had spastic hemiplegia (one side of the body), and 3% were unclassified. Mild CP was present in 32%, moderate CP in 36%, severe CP in 30%, and unknown in 2%.