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Updated: May 25, 2026

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System
Published on: September 20, 2018
Prevalence and risk factors for third- and fourth-degree perineal lacerations during vaginal delivery: a
F Hirayama1, A Koyanagi, R Mori
1Department of Global Health Policy, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Objective:
To investigate the prevalence and risk factors of third- and fourth-degree perineal lacerations in 24, mainly developing, countries.
Design:
Analysis using cross-sectional data from the WHO Global Survey on Maternal and Perinatal Health.
Setting:
Seven African, nine Asian and eight Latin American countries.
Population:
Women at admission to hospital for delivery in 373 facilities between 2004 and 2008.
Methods:
We estimated the country-wise prevalence of third- and fourth-degree perineal lacerations, and conducted region-wise multivariate logistic regression analyses to identify its risk factors.
Main Outcome Measures:
Prevalence and risk factors of third- and fourth-degree perineal lacerations.
Results:
A total of 214,599 women who underwent vaginal delivery were analysed. The prevalence of third- and fourth-degree perineal lacerations ranged widely across countries [from 0.1% (China, Cambodia, India) to 15.0% (Philippines)] and facilities (from null to 76.3%). After the deletion of facilities reporting no third- or fourth-degree perineal lacerations, and also highly outlying facilities, the range in prevalence was 0.1% (Uganda) to 1.4% (Japan). Forceps-assisted delivery, nulliparity and high birthweight were significant risk factors in all three regions. Vacuum-assisted delivery was also a significant risk factor in Africa and Asia.
Conclusions:
Misdiagnosis of third- and fourth-degree perineal lacerations in developing countries may be common. Correct recognition and diagnosis may lead to timely treatment and fewer sequelae. Risk factors of third- and fourth-degree perineal lacerations in developing countries were similar to those previously reported from developed countries.
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