Document Type : Original Article


1 Department of Obstetrics and Gynecology, Shahid Faghihi Hospital, Shiraz, Iran

2 Department of Public Health, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Mother and Child Welfare Research Center, Faculty of Nursing and Midwifery, Hormozgan University of Medical Sciences, Bandar Abbas, Iran


BACKGROUND: Preterm birth (PTB) is one of the most important factors that increase the risk of
chronic diseases and postpartum death in infants. The aim of this study was to determine the maternal
factors that affect the birth of preterm infants in the city of Bandar Abbas.
MATERIALS AND METHODS: This is a case–control study that was performed on 400 preterm
infants. Sampling was done by a simple method, and information was gathered by interviewing the
mothers and their medical records. Data were collected by SPSS software version 16. To compare
risk factors in the two groups, conditional logistic regression was used, and P < 0.05 was considered
statistically significant.
RESULTS: Results showed that factors such as type of delivery (odds ratio [OR] = 3.584, 95%
confidence interval [CI]: 1.981–6.485), preeclampsia (OR = 2.688, 95% CI: 1.164–6.207), history
of PTB (OR = 4.171, 95% CI: 1.483–11.728), premature rupture of membranes (OR = 3.273,
95% CI: 1.745–6.137), care during prenatal (OR = 0.334, 95% CI: 0.159–0.701), placental
abruption (OR = 3.209, 95% CI: 1.209–8.519), placenta previa (OR = 9.333, 95% CI: 2.086–41.770),
and cervical insufficiency (OR = 11, 95% CI: 1.381–87.641) were independent risk factors of preterm
infant birth.
CONCLUSIONS: The PTB risk is higher for women with cervical insufficiency, history of placenta
previa, and history of preterm. Early recognition and management of these high‑risk conditions among
pregnant women may lead to a reduction in PTB rates.


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