To report rates of Medicare Benefits Schedule (MBS) mental health item use among a sample of women who gave birth in NSW (2009‐2015) and examine if the SAFE START policy increased use of these items among perinatal women. Data was drawn from women participating in the Australian Longitudinal Study on Women's Health 1973‐1978 cohort, linked to data from the NSW Perinatal Data Collection and MBS. Use of Medicare‐subsidised mental health items increased 2.7‐fold among perinatal women (n=1,453) between 2009 and 2015 (4.1% versus 11.0% respectively), compared to a 1.3‐fold increase among non‐perinatal women (n=1,800, 6.3% versus 8.4% respectively). However, the increased use of MBS mental health items among perinatal women was not observed to be impacted by the SAFE START policy, after accounting for time trends. There was a substantial increase in the use of MBS mental health items among women in NSW between 2009 and 2015, with a more pronounced increase among women who had given birth compared to those who had not. This study provides important information about changes in mental health service use during a time of significant investment in perinatal mental health, and demonstrates the value of longitudinal survey data linked with administrative health data to evaluate the impact of health policy.