The percentage of babies with low gestational age and the percentage of babies with low birthweight has remained broadly similar across each age group over the last 10 years.
Mae canran y babanod â hyd beichiogrwydd isel a chanran y babanod â phwysau geni isel wedi parhau'n weddol debyg ar draws pob grŵp oedran dros y 10 mlynedd diwethaf.