THRIVE is a five year trial  that will rigorously evaluate whether women who are identified as having additional health and social care needs during pregnancy benefit from receiving parenting support programs in addition to their routine maternity care. In particular, THRIVE will assess whether mothers who receive either Enhanced Triple-P for Baby or Mellow Bumps during pregnancy show one, improved mental well-being and two, more positive, interactive and attuned mother-child relationships with their child when their infants are 6- and 18-months old compared to those that receive routine maternity care alone. Additionally, THRIVE will assess whether children whose mothers received Enhanced Triple-P for Baby or Mellow Bumps show reduced incidence of child maltreatment and improved language development and socio-emotional wellbeing at 6-, 18- and 30-months. Full details of THRIVE and the research questions that will be addressed can be found in the THRIVE research protocol in Appendix B. This dataset is anonymised.