Background: Antenatal care (ANC) services are a prime focus of the Government of India's National Health Mission (NHM), of which a key pillar is the promotion of maternal and child health. To ensure uninterrupted service delivery at the last mile, a cadre of Frontline Health Workers (FLHWs) has been appointed and health centres established at the village level. However, the onset of the COVID-19 pandemic and the nationwide lockdown from late March to June 2020 impacted pregnant women's access to institutional antenatal care services. Methods: Using a qualitative research design, data was collected through 12 in-depth interviews (IDIs) with pregnant women and 17 IDIs with frontline health workers in the selected six districts under study. The narratives were analysed using inductive coding in Atlas.ti. Results: During the first wave of the COVID-19 pandemic, pregnant women, most of whom belonged to poor and marginalised groups, were left with limited access to health centres and FLHWs. Respondents from the study areas of rural Jharkhand, Madhya Pradesh and Uttar Pradesh extensively reported concerns stemming from the lockdown that influenced their decision to access ANC services. These included anxieties around meeting their families' daily needs due to a loss of livelihood (in particular, abject food insecurity), inability to access healthcare, and a sense of mistrust in public health systems and functionaries. All of these, coupled with the real threat to health posed by COVID-19, disrupted their plans for pregnancy and delivery, further compounding the risk to their health and wellbeing. Conclusion: This study identified several social, behavioural and structural facets of the communities that contributed to the confusion, anxiety and helplessness experienced during the COVID-19 first wave by both groups, viz. pregnant women and FLHWs. In planning and implementing initiatives to ensure the delivery and uptake of ANC services in this and similar contexts during times of crisis, these facets must be considered.