Background: Sleep is essential to maternal health during pregnancy, yet nearly half of all pregnant women—49.4% in India and 45.7% globally—experience sleep disturbances. Poor sleep quality (PSQ) during the periconceptional period remains underestimated, despite emerging evidence linking it to adverse maternal and fetal outcomes, including birth defects such as neural tube defects and congenital heart diseases (CHDs).

Objective: Our study aimed to investigate the association between maternal PSQ and the risk of CHDs in offspring.

Methods: A case–control study was conducted involving 587 mothers of 1-year-old infants who underwent echocardiographic evaluation at a free-of-cost tertiary pediatric cardiac hospital in 2024. The participants included 402 CHD cases—categorized as acyanotic (n=234) and cyanotic (n=168), as well as simple (n=214) and severe (n=188) defects—and 185 controls. Maternal sleep quality during the periconceptional period was assessed using the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Data was analyzed using SPSS software.

Results: The prevalence of PSQ was markedly higher in mothers of CHD patients (77.3%) compared to controls (56.7%). Subgroup analysis revealed PSQ rates of 78.6% in acyanotic CHD, 75.5% in cyanotic CHD, 78.9% in simple CHD, and 75.5% in severe CHD. PSQ was associated with significantly increased odds of CHDs: a 2.8-fold increase for acyanotic CHD (p < 0.0001; 95% CI: 1.83-4.29), 2.4-fold for cyanotic CHD (p = 0.0002; 95% CI: 1.49-3.73), 2.9-fold for simple CHD (p < 0.0001; 95% CI: 1.85-4.44), and 2.4-fold for severe CHD (p = 0.0001; 95% CI: 1.51-3.66).

Conclusion: This is the first comprehensive Indian study to link maternal PSQ and CHDs. The findings underscore the urgent need for targeted interventions, including adequate night-time sleep, mindfulness yoga, regular physical activity, a healthy diet, psychoeducation, counseling, limited caffeine and sugar intake, therapies such as continuous positive airway pressure and cognitive behavioral therapy for insomnia, maintaining a left-side sleep posture, and the careful use of medications for mental health and sleep disorders.