Background Antenatal women experience a higher level of mood symptoms, which have negative effects on mothers’ mental and physical health and their newborns. The relation of maternal moods including depression and anxiety and other maternal factors in pregnancy and neonate outcomes are well-studied with inconsistent findings. Although antenatal women experience a higher level of mood instability (MI), the association between antenatal MI and neonatal outcomes has not been investigated. We aimed to address this gap and to contribute to the pregnancy-neonate outcomes literature by examining the relationship between antenatal mood symptoms and other maternal factors and neonatal outcomes.Methods A prospective cohort of women (n = 555) participated in this study at early pregnancy (T1, 17.4 ± 4.9 weeks) and late pregnancy (T2, 30.6 ± 2.7 weeks). The Edinburgh Postnatal Depression Scale (EPDS) was used to assess antenatal depressive symptoms, the EPDS anxiety subscale was utilized to measure anxiety symptoms, and mood instability was measured using a visual analogue scale. These mood states together with stress, social support, as well as healthy and unhealthy behaviours were also examined in relation to neonatal outcomes using chi-square tests and logistic regression models. Results Depression and MI were unrelated to adverse neonatal outcomes and anxiety was related to Apgar score with marginal statistical significance. Higher stress, lack of partner support, smoking, and primiparous status were associated with some adverse outcomes.Conclusions The current study identified no associations between antenatal mood symptoms and neonatal outcomes. Our findings further support and extend previous evidence on smoking abstinence or cessation, and the provision of resources for stress management and social support that could help prevent or alleviate adverse neonatal outcomes.