Background: The COVID-19 pandemic has intensified economic hardships, with potential negative impacts on food insecurity and infant feeding beliefs and practices. The relationship between food insecurity and infant feeding beliefs and practices during the pandemic is not yet fully understood. Neither is how these relationships changed over the course of the waves of the pandemic. We examined these relationships in a cohort of infants born during the various waves of the COVID-19 pandemic in New York City (NYC). Methods: We conducted a cross-sectional analysis of infants enrolled from birth into the COVID-19 Mother-Baby Outcomes (COMBO) study and born March 2020 to May 2024. We measured food insecurity in the prior 30 days with a 2-item survey adapted from Hunger Vital Sign, infant feeding confidence at hospital discharge, and current infant feeding practices. Results: 40% of women in our sample had been exposed to prenatal SARS-CoV-2 infection and approximately 24% of mothers were food insecure. There was a significant association between food insecurity and prenatal SARS-CoV-2 infection, Spanish as one's preferred language, and self-identifying as Latina. In unadjusted models of the entire sample, food insecurity was associated with formula feeding (p<0.001), but this relationship was no longer significant after adjusting for covariates (p=0.059). In comparing the first and second waves of the pandemic (March 2020-December 2021 vs. January 2022-May 2024), there was no significant difference in rate of food insecurity. When comparing different waves of the pandemic, food insecurity was associated with increased likelihood of formula feeding, even after adjusting for confounders. Discussion: Food insecurity was initially associated with feeding methods, but this relationship lost significance after adjusting for confounders. However, when analyzed separately, food insecurity was significantly linked to lower odds of exclusive breastfeeding during different waves of the pandemic, suggesting the influence of external factors like policy changes and social support variations. Other factors, such as maternal BMI, ethnicity, and delivery mode, were also significantly associated with breastfeeding practices, highlighting the need for targeted interventions to support breastfeeding, especially among food-insecure mothers.

The authors have declared no competing interest.

This study was supported in part by the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant Number KL2TR001874.

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Ethics committee/IRB of Columbia University Irving Medical Center gave ethical approval for this work.

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