Globally, the impact of COVID-19 on mental health has been significant. Pregnant women are known to be a vulnerable population in relation to mental health. In Australia, there was an unprecedented demand during the pandemic for mental health services, including services for pregnant women. Maternal mental health has unique and enduring features that can significantly shape a child’s overall development and poor maternal mental health can have considerable social and economic costs. This cross-sectional study evaluated symptoms of antenatal depression and COVID-19-related distress in a sample of two hundred and sixty-nine pregnant women residing in Australia aged between 20 and 43 (M = 31.79, SD = 4.58), as part of a larger study. Social media advertising was used to recruit participants between September 2020 and November 2021. Prevalence rates for antenatal depression were found to be higher in this study (16.4%) compared with previous Australian prevalence rates (7%). COVID-19 distress in relation to having a baby during a COVID-19 outbreak significantly predicted symptoms of antenatal depression, B = 1.46, p < 0.001. Results from this study suggest that mothers and families may have increased mental health vulnerabilities as a consequence of the pandemic for some time yet.