Gastroschisis and omphalocele in Finland in the 1970s: prevalence at birth and its correlates.

Information on liveborn and stillborn children with gastroschisis and omphalocele was collected from hospital and register sources in Finland from 1970 to 1979. The apparent prevalence of gastroschisis at birth increased from 0.77/10 000 births in 1970-4 to 1.42/10 000 in 1975-9. The prevalence of omphalocele (1.96/10 000) was unchanged during the decade. Even for gastroschisis the apparent increase in prevalence was noted for northern Finland only, while for southern Finland the prevalence has been stable during the 1970s, possibly suggesting diagnostic or reporting differences between various parts of the country. Some correlates of increased risk of gastroschisis included: low birth weight, low maternal age, urban residence, and maternal employment in commercial and sales work.