Background: There exists little evidence that routine assessment of current or past mental health in the perinatal period positively impacts on rates of referral for emotional health issues. This study aimed to evaluate the impact of this early intervention approach on reported referrals for emotional health issues during pregnancy and the first postpartum year. Method: A subsample of women (N = 1,804) drawn from the Australian Longitudinal Study on Women's Health participated in the study. Results: Multivariate analyses showed that predictors of being given a referral for emotional health issues during pregnancy and the postnatal period, respectively, included assessment of past mental health (Adjusted Odds Ratio [AOR] = 4.40, p < 0.001, and AOR = 5.69, p < 0.001), assessment of current mental health (AOR = 2.47, p < 0.001, and AOR = 2.72, p < 0.001), and reported experience of significant emotional distress (AOR = 2.58, p < 0.001, and AOR = 2.83, p < 0.001). The odds of receiving a referral were up to 16 times greater for women who were asked about both their past and current mental health than for women who did not receive any form of mental health assessment. Conclusions: This study highlights that enquiry into risk factors such as past history (in addition to current mental health) enhances initiation of referrals. Importantly, results suggest that enquiry about current mental health is associated with appropriate rates of referral rather than a nonspecific inflation of referrals. In line with Australia's Clinical Practice Guidelines for Perinatal Mental Health, the value of a comprehensive approach to mental health assessment to aid decision making around referral for further assessment or care is particularly evident.