Cerebral palsy or physical disability more common in firstborn child?

Is cerebral palsy and physical disabilities more common in firstborns than in later borns? I heard that it is true. In my personal experience, I find it is true too. People I know with cerebral palsy and people who are on wheelchairs because of birth defects are all firstborns. Why? And also cerebral palsy and physical disabilities are caused by the mother having certain blood disorders and nervous system problems.

Not exactly true. I am wondering why you have this question - maybe faced with this syndrome or are concerned about your first born or someone else?

Regardless, cerebral palsy can occur with any child and not only during pregnancy. Cerebral (meaning brain) palsy (meaning weakness or paralsis) happens from an injury to or abnormal development of the brain. This can come from infection or injury. Physical disabillities can also happen to anyone at anytime. I am not aware of these pertaining specifically to first-born children. Some physical diabilities can be genetic but not cerebral palsy. Blood disorders will not cause either CP or physical diability and neither will a nervous system problem. However, you or whoever is the reason for this question will get a full exam by the dr before, during and after pregnancy to spot anything unusual. If you know that you have certain disorders or genetic predisposition to certain illnesses or disabilities, talk with your OB before or during pregnancy to best determine ways to reduce the baby's exposure to risks.

This is only true for some disabilities. Cerebral Palsy is caused by not getting enough oxygen to the brain during birthing. If the mother has a particularly hard time delivering, the chances of cerebral palsy are greatly elevated....usually the first kid is the hardest to deliver. However, Downs Syndrome is more common to later born children, purely because of the age of the mother when she gets pregnant.