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Pre- and perinatal risk factors for pyloric stenosis and their influence on the male predominance

Camilla Krogh1, Sanne Gørtz, Jan Wohlfahrt

  • 1Department of Epidemiology Research, Statens Serum Institut, 5 Orestads Boulevard, DK-2300 Copenhagen S, Denmark. ckr@ssi.dk

American Journal of Epidemiology
|May 4, 2012
PubMed

Insights

Pyloric stenosis, a condition affecting infants, shows a strong male predominance. This study reveals that environmental factors, such as maternal smoking and preterm birth, influence its occurrence and also reduce the male-to-female ratio.

Area of Science:

  • Pediatric Surgery
  • Epidemiology
  • Environmental Health

Background:

  • Pyloric stenosis exhibits a significant male predominance, suggesting potential contributing factors beyond genetics.
  • The role of environmental exposures in the etiology and sex ratio of pyloric stenosis remains largely unexplored.

Purpose of the Study:

  • To investigate the association between pre- and perinatal environmental exposures and the risk of pyloric stenosis.
  • To determine if these environmental factors modify the observed male predominance in pyloric stenosis.

Main Methods:

  • A nationwide cohort study of children born in Denmark between 1977 and 2008.
  • Utilized national registers for data on pre- and perinatal factors and pyloric stenosis diagnoses.
  • Employed Poisson regression models to calculate rate ratios for identified risk factors.

Main Results:

  • Pyloric stenosis was associated with male sex, diagnosis between 2-7 weeks, early study period, firstborn status, maternal smoking, preterm delivery, low birth weight for gestational age, cesarean section, and congenital malformations.
  • A reduced male predominance was observed with later age at diagnosis, early study period, absence of maternal smoking, preterm delivery, and congenital malformations.
  • The study identified 3,174 cases of pyloric stenosis among 1,925,313 children, with 2,595 males and 579 females.

Conclusions:

  • Environmental factors during and shortly after pregnancy significantly contribute to the development of pyloric stenosis.
  • These environmental exposures play a role in modulating the strong male predominance observed in this condition.
  • Findings suggest a complex interplay between genetic predisposition and environmental influences in the etiology of pyloric stenosis.

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