To investigate the influence of partners on alcohol consumption in pregnant women within the context of other factors. A Dutch nationwide online cross-sectional study among 158 pregnant women and their partners was conducted. To identify correlates of prenatal alcohol use, including perceived and reported partner norm (i.e. partner's belief regarding acceptability of prenatal alcohol use), partner modeling (i.e. partner's alcohol use during the woman's pregnancy) and partner support (i.e. partner's help in abstaining from alcohol during pregnancy), independent sample T-tests and Chi square tests were conducted. Correlation analyses tested the relationship between perceived and reported partner influence. Multivariate logistic hierarchical regression analyses tested the independent impact of partner's perceived and reported influence next to other correlates from the I-Change Model. Pregnant women who consumed alcohol perceived a weaker partner norm (p <0.001) and less partner modeling (p <0.05), with the partner reporting a weaker norm (p <0.001), more drinking days per week (p <0.05) and weaker support (p <0.05). Perceived and reported partner norm, modeling and support were positively related (respectively p <0.01, p <0.01 and p <0.05). The multivariate analyses demonstrated that pregnant women with a higher education who perceived lower severity of harm due to prenatal alcohol use and a weaker partner norm were more likely to use alcohol (R-2 = 0.42). This study demonstrated that perceived partner norm was the most critical of the constructs of perceived and reported partner influences in explaining prenatal alcohol use.