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Seasonal variation in fetal growth: accounting for sociodemographic, biological, and environmental exposures

Gavin Pereira1, Angus Cook, Fatima Haggar

  • 1School of Population Health, The University of Western Australia, Crawley, Sydney, New South Wales, Australia. gavin.pereira@uwa.edu.au

American Journal of Obstetrics and Gynecology
|October 11, 2011
PubMed

Insights

Seasonal variations in temperature impact fetal growth. Higher temperatures during pregnancy, particularly in the third trimester, were linked to reduced optimal birthweight and increased risk of babies being small for gestational age.

Area of Science:

  • Environmental Epidemiology
  • Perinatal Health
  • Reproductive Biology

Background:

  • Seasonal variations can influence fetal development.
  • Sociodemographic, biological, and environmental factors play a role in fetal growth.
  • Understanding these influences is crucial for public health initiatives.

Purpose of the Study:

  • To investigate seasonal variations in fetal growth.
  • To assess the impact of temperature, season, and sunlight on fetal growth.
  • To account for sociodemographic, biological, and environmental exposures.

Main Methods:

  • Utilized birth records from Perth, Western Australia (1998-2006, N=147,357).
  • Examined small for gestational age (SGA) and proportion of optimal birthweight (POBW).
  • Analyzed seasonal exposures (season, temperature, sunlight) by trimester, adjusting for risk factors.

Main Results:

  • Third-trimester summer births showed 0.18% lower POBW than winter births.
  • Increased third-trimester temperature (9.15°C IQR) correlated with a 0.14% decrease in POBW.
  • Elevated temperature throughout pregnancy (0.73°C IQR) increased odds of SGA by 1.02 (1.00-1.05).

Conclusions:

  • Elevated ambient temperatures during pregnancy are associated with reduced fetal growth.
  • This association is independent of air pollution and other identified risk factors.
  • Findings highlight the impact of environmental temperature on perinatal outcomes.
Abstract

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