Summary

The study covers over 200 000 pregnancies and gives a unique opportunity to gain knowledge about factors that increase the risk of cerebral palsy. 

Approximately two per 1000 babies born develop the disease. Even though it is the most frequent cause of physical handicap in childhood, the incidence is so rare that it is necessary to collect data from both Norway and Denmark to obtain sufficient material to study possible risk factors. It is hoped that research findings from the study can help to identify measures to prevent CP.

Purpose

• To describe the incidence, progression and consequence of the disease and mortality among children with CP.
• To identify possible causes and risk factors for CP.

Data and method

More than 90 000 pregnant women were recruited in the period 1999-2008, with over 100 000 pregnancies. BSMB in Denmark started to recruit pregnant women in 1996 and had achieved their goal of 100 000 pregnancies.

Data collection in both countries began early in pregnancy and the children have been followed from birth and through childhood. The same types of information about the participants are collected, via questionnaires in Norway, and telephone interviews and questionnaires in Denmark. Blood samples were also taken from the mothers during pregnancy and from the umbilical cord just after birth.

In MoBa, data about disease, diet, environmental contaminants and socioeconomic conditions were collected from questionnaires completed by the mother during pregnancy as well as information about each child's development from questionnaires at 6 months, 18 months, 36 months and 5 years are used in the study.  These data will be stored with information about birth outcome from the Medical Birth Registry of Norway.

In order to identify all cases of CP in MoBa, data from the questionnaires from pregnancy are combined with data from the Cerebral Palsy register in Norway (CPRN), the National Patient Registry (NPR) and the social security database (FD-Trygd). In the cases where it is uncertain whether the child has CP, information from the hospital records will be collected to confirm the diagnosis. 

In Denmark, the equivalent information comes from BSMB and the Danish CP register.

• Den norske mor og barn-undersøkelsen (MoBa)
• BSMB: Bedre sundhed for mor og barn
• Cerebral pareseregisteret i Norge (CPRN) (Sykehuset i Vestfold)
• Cerebral Parese Registret i Danmark

Collaborative partners/Organisation

The study is a close collaboration with University of Bergen, Statens Serum Institutt in Denmark and the National Institute of Environmental Health Sciences (NIEHS) in USA.

It is led by a steering group that includes Camilla Stoltenberg (Director-General at Norwegian Institute of Public Health), Jørn Olsen (leader of BSMB) and Allen Wilcox (NIEHS).

A scientific committee that includes Nigel Paneth (Michigan State University), Karin B. Nelson (National Institute of Neurological Disorders and Stroke, USA) and Eve Blair (the University of Western Australia) will advise the study.

In 2012, a working group began to harmonise the Norwegian and Danish data and identify the cerebral palsy cases.  Danish and Norwegian researchers are in the group which is led by Dag Moster at the Norwegian Institute of Public Health.

Approval

The study is approved by the Regional Ethics Committee (REK).

Funding

The establishment of the study is financed by the National Institutes of Health (NIH), USA.

Results from the study

The results from the study will be published in scientific journals and presented at meetings and conferences. The results will also be communicated via the press and on this website. All participants are informed about the results in the annual newsletter from MoBa.