The thesis investigated the role of maternal mental health, maternal attachment and hormones in the development of maternal-fetal attachment during pregnancy. The study found that oxytocin and cortisol were associated with maternal-fetal attachment throughout pregnancy. The study also found that maternal mental health, particularly anxiety, stress and depression during the prenatal period impacted on the development of maternal-fetal attachment across pregnancy. The findings have clinical and research implications with regard to early intervention for attachment and maternal well-being.