A cohort of 159 mothers were recruited post-partum and followed for seven months to examine the relationship between mothers’ health post-partum and their patterns of seeking vaccination for their infants. Vaccination records for infants were obtained from a state-wide database. Only 44% of the mothers had maintained all age-appropriate vaccinations for their infant up to six months of age. Mothers who had two or more older children were four times more likely to have an infant who was not age-appropriately vaccinated at six months. Women experiencing mental health problems including anxiety and depression, seven months following the birth, were between three to five times more likely to have started the vaccination schedule late or not at all. The findings have implications for midwives and for nurses practising in maternal and child health, paediatrics and public health environments. Strategies focusing on enhancing mothers’ psychosocial well-being postnatally through improved service delivery should improve their patterns of seeking vaccination for their infants.