The Norwegian Mother and Child Cohort Study (MoBa) was planned in the 1990s partly by
researchers at the Medical Birth Registry of Norway (MBRN) 1 and partly by researchers at
the National Institute of Public Health (from 2002 comprising MBRN as well as other
institutions and renamed the Norwegian Institute of Public Health (NIPH). The study had a
long planning phase involving many scientists who contributed ideas that helped to design
questionnaires and to structure the biobank, which is described in detail elsewhere. 2�…

This is an update of the Norwegian Mother and Child Cohort Study (MoBa) cohort profile
which was published in 2006. Pregnant women attending a routine ultrasound examination
were initially invited. The first child was born in October 1999 and the last in July 2009. The
participation rate was 41%. The cohort includes more than 114 000 children, 95 000
mothers and 75 000 fathers. About 1900 pairs of twins have been born. There are
approximately 16 400 women who participate with more than one pregnancy. Blood�…