Background: Perinatal factors during delivery might modulate fetal immunological development and thereby be associated with the development of allergic diseases and asthma later.
Methods: Perinatal data was recorded during pregnancy and at the time of delivery in regard to 5823 children who were born in Northern Finland in 1985-1986. Data from self-administered questionnaires were available at the ages of 7 and 15-16 years and skin prick tests for four main allergens were carried out at the age of 15-16 years. Only singletons delivered by the vaginal route were analyzed.
Results: There was a higher prevalence of doctor-diagnosed asthma at any time of life among children who were delivered by vacuum extraction (RR 1.80, 95% CI 1.27-2.56; P < 0.001) in comparison with spontaneously delivered children. In particular, this risk was increased as regards late-onset asthma (RR 2.41, 95% CI 1.52-3.81; P < 0.001). Perinatal effects had less impact on the development of other asthma, atopy or hay fever.
Conclusions: The delivery by vacuum extraction had significant impact on the development of late-onset asthma compared with spontaneously delivered children.