Objective To investigate the extent to which Danish women attending antenatal care plan their pregnancies and to determine the association between pregnancy planning and the intake of folic acid, alcohol consumption and smoking habits prior to conception and before the 16th week of gestation. Methods A cross-sectional survey of 258 women. Main outcome measures: intake of folic acid, alcohol consumption and smoking. Pregnancy planning was assessed by the London Measure of Unplanned Pregnancy (LMUP) and the five graded Swedish Pregnancy Planning Scale. Results Most (77%) of the participants reported that their pregnancies were very or fairly well planned. Higher median LMUP scores were observed in women taking folic acid (p < 0.001), in those consuming less alcohol, and in women who stopped smoking prior to pregnancy (p = 0.043). However, 43% of the respondents with a high degree of pregnancy planning and 98% of those with a low degree of planning had not taken folic acid prior to pregnancy. Binge drinking during early pregnancy was reported by 20% of women with a high degree of planned pregnancy and 31% of those with a low degree (p = 0.1). Conclusion Pregnancy planning was associated with a healthier lifestyle but still many women could improve their lifestyle in connection to pregnancy. Their level of alcohol consumption is higher than that recommended for best pregnancy outcome.