# Maternal risk factors associated with the birth of preterm infants in the West of Iran: a matched case-control study

## TL;DR

This study identifies maternal risk factors linked to preterm births in Iran, aiming to reduce infant mortality and healthcare costs.

## Contribution

The study identifies specific maternal risk factors for preterm birth in a specific Iranian population using a matched case-control design.

## Key findings

- Maternal employment, history of abortion, pre-eclampsia, premature rupture of membranes, and placental abruption were significantly associated with preterm birth.
- Sexual activity during late pregnancy was inversely associated with preterm birth.
- Factors like mother’s age and number of prenatal cares did not significantly influence preterm birth.

## Abstract

Preterm birth is one of the global most common causes of mortality among infants, especially in developing countries. Therefore, the present study was conducted to determine the maternal risk factors related to the birth of preterm infants.

The present case-control study was conducted on 220 premature infants as the case group and 440 term infants as the control group in the hospitals of Khorram Abad, Iran, in 2023. Two groups were matched in terms of gender and date of birth. Data were gathered by the researcher using a researcher-made questionnaire, interviewing the mothers and physicians, and reviewing mothers’ medical files in maternity and postpartum wards. Data were analyzed using Stata 17 software and descriptive statistics and conditional logistic regression test at the significance level of less than 0.05.

In multivariable analysis adjusted odds ratio (AOR) was estimated, mother’s employment (AOR: 2.85; 95%CI:1.05–7.77), history of abortion (AOR: 2.04; 95%CI: 1.10–3.78), sexual activity from 32nd to 36.6th week of pregnancy (AOR: 0.33; 95%CI: 0.20–0.54), pre-eclampsia (AOR: 11.09; 95%CI: 4.5-27.39), premature rupture of membrane (AOR: 6.76; 95%CI; 3.7-12.34) and placental abruption (AOR: 16.07; 95%CI: 5.45–47.39) were significantly associated with preterm birth of infants. No significant relation was observed between mother’s age, assisted reproductive treatment, cervical insufficiency, and the number of received prenatal cares at the health centers and the birth of premature infants.

According to the results of the study, factors such as a mother’s employment, history of abortion, pre-eclampsia, premature rupture of membranes, and placental abruption can affect the birth of premature infants. Therefore, the control of maternal factors influential in the birth of premature infants, as well as care during pregnancy, can reduce the occurrence of premature births, followed by the reduction of healthcare costs and infant mortality and the improvement of the youth level of the population.

The online version contains supplementary material available at 10.1186/s12884-025-07395-5.