Aim: We aim to compare the past trajectory of immunization services and different types of follow-ups with their current states during the COVID-19 pandemic. Methods: This cross-sectional study was conducted in a district of Istanbul in February 2020, and included 138 Family Medicine Units. Services were compared monthly between 2019 and 2020, based on the antenatal, postpartum, infant, child follow-ups, and vaccine doses provided by the units. To examine the impact of the pandemic, the April-December periods of both years were also compared. Results: It was found that follow-ups and immunizations were continued without any decline despite an increase in delayed vaccines. When the monthly mean number of delayed vaccines were compared, the mean number of delayed vaccines was significantly higher in April-May-June 2020 than in the same months of the previous year. Conclusion: Performance scores of different services do not differ according to the descriptive characteristics of physicians. Although physicians are successful in services such as follow-ups, delayed vaccines are prevalent among them as well. While services that can be carried out remotely seem to be continued, services that require face-to-face contact are interrupted. Interventions should be done to ensure the sustainability of indispensable services even during extraordinary times. Keywords:.