Incidence rate of and risk factors for anorectal diseases in primiparae in the first 6 weeks following delivery.

OBJECTIVES

We aimed to explore the incidence rate of and risk factors for anorectal diseases in primiparae in the first 6 weeks following delivery, and to establish a risk evaluation model for the early identification of high-risk groups and precise intervention.

METHODS

Subjects (350 in total) in this prospective observational cohort study were recruited from eligible primiparae who delivered between January 2023 and January 2025. The pregnancy data, intrapartum data and postpartum follow-up (completed at 1 week, 3 weeks and 6 weeks following delivery) data were acquired. Relevant variables were identified using univariate analysis plus Least Absolute Shrinkage and Selection Operator regression, and a machine learning Logistic regression prediction model was constructed.

RESULTS

Finally, 326 of the enrolled 350 primiparae finished the follow-up, with a completion rate of 93.14 %. The incidence rate of anorectal diseases in the first 6 weeks after delivery was 29.14 %. Prolonged second stage of labor, elevated fetal birth weights, increased pre-pregnancy body mass index (BMI), a history of gestational constipation, and epidural anesthesia served as independent risk factors (p<0.001). The area under the curve (AUC) of the prediction model was 0.928, which was well calibrated, and the mean AUC by 5-fold cross-validation was 0.865, implying good discrimination and generalization ability. The constructed nomogram realized individualized risk assessment.

CONCLUSIONS

Prolonged second stage of labor, large fetal weights, high pre-pregnancy BMI, gestational constipation, and epidural anesthesia are considered independent risk factors. The model supports screening high-risk groups and improving postpartum anorectal health management.