THE PATTERN OF SEASONAL DISTRIBUTION OF PRETERM DELIVERY IN ARDABIL COUNTY

Some of the causes of preterm delivery almost are known but its biological
mechanisms are unknown. There is evidence that shows preterm delivery is related with different
seasons of the year. Finding environmental factors affecting biological mechanisms is important steps
to reduce preterm delivery. This study aims to determine the seasonal distribution of preterm delivery
in Ardabil County.
Material & Methods: This research has been done as a descriptive-analysis with a retrospective
approach, using hospital cases and climatic data at Sabalan hospital in Ardabil County has analysed 759
pregnant women (n= 10860) who had preterm delivery complication during the weeks 20-36 over the
time from March 2011-Feburury 2016. In this study, statistical data analysis using descriptive statistical
methods and correlation relations were carried out by SPSS software 20.
Results: There were% 6.98 preterm delivery among 10860 natural birth. Maximum preterm delivery
outbreak was in winter (% 7.95) (P<0.05) and its minimum outbreak was in summer (% 6.22) that was
variable with changing of seasons disticly.
The maximum frequency of preterm delivery was on Aban% 8.91 and minimum on Shahrivar% 4.50,
also the ratio of preterm delivery according to Seasonal Index (SI) showed that the maximum frequency
was on Tir with index of 133.44 and its minimum on Shahrivar with 58.85.
Conclusion: Preterm delivery followed seasonal pattern according to research findings in Ardabil
County