Assessments are usually carried out between 9 & 11 months by a public health nurse.
Thousands of babies in Kildare and West Wicklow have not had key developmental checks on time.
Public health nurse visits and screening checks have been curtailed and delayed as a result of the pandemic.
It has now emerged that 3,235 babies in the county, and in western Wicklow, have no had the developmental assessment which takes place between 9 and 11 months.
These assessments check motor skills, eyesight, hearing, speech development and social and emotional behaviour.
Kildare Senator, Fianna Fáil's Fiona O'Loughlin, speaking in the Oireachtas on the matter, says "We all talk about how important early intervention is and this is the time when many of these issues can be picked up. This is adding to the stress of first-time parents and there is an absolute necessity for a plan to be put in place. I call on the HSE to urgently roll out a catch-up programme for Kildare and west Wicklow. I have no doubt it is the same around the country."