37% of children aged under four in Merthyr Tydfil were on Flying Start health visitor caseloads (the highest in Wales), compared to 16% in Monmouthshire (the lowest in Wales).
Roedd 37% o blant o dan 4 oed ym Merthyr Tudful ar lwyth achosion ymwelwyr iechyd Dechrau’n Deg (yr uchaf yng Nghymru), o gymharu ag 16% yn Sir Fynwy (yr isaf yng Nghymru).