Vaginal bleeding during pregnancy and adverse pregnancy outcomes: a nationwide population-based retrospective cohort study in Iran.

Publisher: BioMed Central Country of Publication: England NLM ID: 100967799 Publication Model: Electronic Cited Medium: Internet ISSN: 1471-2393 (Electronic) Linking ISSN: 14712393 NLM ISO Abbreviation: BMC Pregnancy Childbirth Subsets: MEDLINE

Original Publication: London : BioMed Central, [2001-

Uterine Hemorrhage*/epidemiology ; Pregnancy Outcome*/epidemiology ; Premature Birth*/epidemiology ; Infant, Low Birth Weight* ; Stillbirth*/epidemiology; Humans ; Female ; Pregnancy ; Iran/epidemiology ; Retrospective Studies ; Adult ; Fetal Membranes, Premature Rupture/epidemiology ; Pregnancy Complications/epidemiology ; Young Adult ; Prevalence ; Infant, Newborn ; Pre-Eclampsia/epidemiology ; Diabetes, Gestational/epidemiology ; Risk Factors ; Logistic Models

Competing Interests: Declarations. Ethics approval and consent to participate: Informed consent was obtained from all participants in the study. Informed consent was obtained from their legal guardians/husbands for all the illiterate participants and participants below 16 years. Informed consent was obtained from LAR (legally authorized representative). The data of the participants were anonymously analyzed. This study was approved by the Ethics Committee of Kermanshah University of Medical Sciences (IR.KUMS.REC.1397.114). All methods were carried out by relevant guidelines and regulations. This study was conducted by the Declaration of Helsinki. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.
Background: Vaginal bleeding (VB) as a common pregnancy problem affects approximately one fourth of pregnancies and leads to abortion in 50% of cases. The occurrence of vaginal bleeding during pregnancy heightens the probability of experiencing diverse adverse pregnancy outcomes. The existing scientific research regarding the relationship between vaginal bleeding and adverse pregnancy outcomes in Iranian women is restricted and presents conflicting findings. Consequently, this research examines the association of vaginal bleeding during pregnancy and unfavorable outcomes in Iranian women.
Methods: This population based retrospective cohort study was conducted in 11 provinces of Iran. The necessary data were collected using the questionnaires and medical records from 3634 pregnant women. The association between vaginal bleeding and stillbirth, premature birth, low birth weight, premature membrane rupture of the membranes (PPROM), gestational diabetes, and pre-eclampsia was done using univariable and multivariable logistic regression.
Results: The prevalence of vaginal bleeding has a declining trend based on BMI and birth cohort of women. Multivariable logistic regression showed that the odds of low birth weight (OR = 1.52, 95%CI: 1.04-2.24), PPROM (OR = 2.12, 95%CI: 1.19-3.76), preterm birth (OR = 1.74, 95%CI: 1.19-2.56), and stillbirth (OR = 2.10, 95%CI: 1.59-2.77) are significantly higher in women who experience vaginal bleeding during pregnancy in compared to women who do not have vaginal bleeding.
Conclusions: Although a declining trend of vaginal bleeding was found, these findings indicate an increased risk of stillbirth, preterm birth, and low birth weight due to VB. Educational interventions to prevent adverse pregnancy outcomes among high-risk women are suggested.
(© 2025. The Author(s).)

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Keywords: Preterm birth; Stillbirth; Vaginal bleeding; Women

Date Created: 20250221 Date Completed: 20250222 Latest Revision: 20250224

20250225

PMC11846370

10.1186/s12884-025-07324-6

39984896