Interpreting maternal and neonatal outcomes in COVID-19-affected pregnancies

Sir,

We read with interest the article by Banerjee et al¹ published in the November 2025 issue of the Indian Journal of Medical Research, examining maternal and neonatal outcomes among women affected by COVID-19 during pregnancy. The article considers a critical maternal-public health problem connected with COVID-19 in pregnancy, which remains relevant over the years, even in the post-pandemic period, as it deals with preparedness, antenatal care measures, and maternal-foetal risk stratification. The authors can be commended for tackling a problem with significant public health implications and for the inclusion of Indian evidence to a growing body of knowledge.

Nonetheless, we would like to highlight some of the methodological and interpretative aspects that should be approached carefully when interpreting the findings.

First, the observational structure of the study, although suitable, restricts causal inference. Exposure to COVID-19 seems to be described more as a binary variable than as being stratified by the level of disease severity, timing of infection during pregnancy, symptom burden, viral variant, or treatment received. These variables have been known to play an important role in maternal and perinatal outcomes, and their exclusion can cover up significant risk gradients.²

Second, the study population was facility-based and may have over-represented women with higher obstetric risk profiles. This increases the risk of selection and referral bias, that is, unfavourable results can be a manifestation of maternal comorbidities or patterns of seeking healthcare and not an independent impact of COVID-19 infection.

Third, the study employed propensity score matching, and considered a number of maternal and obstetric factors, but residual confounding cannot be excluded, especially with regard to the nutritional status, socioeconomic determinants, disease severity, and health-system factors. Furthermore, including downstream variables that could be on the causal pathway, including mode of delivery, which may be between maternal COVID-19 infection and obstetric decision-making and neonatal outcomes, could have resulted in over-adjustment, thereby affecting estimated effect sizes.³ Additionally, lack of facility-level or regional clustering adjustments across various pandemic phases could have influenced in estimating outcomes.

We also observe that some conclusions seem to suggest a direct causality between COVID-19 and poor pregnancy outcomes. Based on the study design possibilities, such as the disruption of healthcare systems, increased monitoring of infected women, or the change in obstetric decision-making under the impact of the pandemic, should have been given more attention. Additionally, the threat of heightened risk perception due to COVID-19, resulting in increased medicalization of pregnancy and the consequences thereof were not investigated by the authors.^4,5

Despite these limitations, the study provides valuable data, and it should be noted that future research that includes severity-stratified analyses, trimester-specific exposure measurement, health system-adjusted research, etc., would be helpful to determine the true effect of COVID-19 on maternal and neonatal outcomes in India.