Familial, environmental, and pregnancy-related risk factors for anorectal malformations in Pakistani newborns: a hospital-based case-control study.

OBJECTIVE: The present study aimed to investigate the familial, environmental, and pregnancy-related factors associated with anorectal malformations (ARM) in newborns in Pakistan. METHODS: A hospital-based case–control study was conducted at a tertiary referral hospital in the Rawalpindi-Islamabad region between January and July 2025. This study assessed maternal, paternal, and environmental risk factors associated with ARM. A total of 102 children with ARM were included, along with 225 children without congenital anomalies who served as controls and were frequency matched by age group and sex. Structured interviews and medical records were used to collect data on parental characteristics, consanguinity, exposure to environmental factors, medication use, and pregnancy-related factors. Logistic regression was performed to estimate crude and adjusted odds ratios (ORs) with corresponding 95% confidence intervals (CIs). RESULTS: Consanguineous marriage was significantly more common among parents of children with ARM than among parents of controls (aOR = 2.42; 95% CI: 1.41–4.16; p = 0.001). Similarly, a positive family history of congenital anomalies was strongly associated with ARM (aOR = 4.15; 95% CI: 2.13–8.08; p < 0.001). Mothers in these cases also had a greater level of exposure to industrial cleaning agents during the periconceptional period (aOR = 2.60; 95% CI: 1.17–5.77; p = 0.019). Moreover, urogenital infection during pregnancy was more frequently reported by mothers of affected children (aOR = 3.12; 95% CI: 1.04–9.36; p = 0.041). CONCLUSIONS: These findings suggest that ARMs are associated with familial factors, particularly consanguinity and a family history of congenital anomalies, as well as maternal exposures and infections during pregnancy. These results may inform targeted genetic counseling and antenatal risk assessment strategies in high-risk populations, alongside efforts to improve preconception and antenatal care and promote awareness of potentially harmful environmental and medication exposures during early pregnancy.