To investigate the issues that confront women when addressing overweight and obesity before conception.

Questionnaire-based study of 412 unselected women in early pregnancy.

255 women who attended a public, antenatal “first visit” clinic at a major urban obstetric hospital in Brisbane and 157 women who presented to a private obstetrician in Brisbane for a routine ultrasound scan during a 6-week period in 2006 were surveyed.

Preconception health activities, prepregnancy body mass index (BMI), self-reported weight category, attempts to lose weight before pregnancy, and weight loss advice received before pregnancy.

Folic acid supplementation was reported by 56% of participants, and 53% attended a preconception health check. Of women who provided details of height and prepregnancy weight, 30% were overweight or obese before pregnancy. However, 23 of 65 women with a BMI in the overweight range categorised themselves as normal weight (36%), and only 8 of 50 women with a BMI in the obese range categorised themselves as obese (16%). As BMI increased, more women reported trying to lose weight (P < 0.001) and reported receiving advice regarding weight loss (P < 0.001). Prepregnancy weight loss was reported by 52 of 115 overweight and obese women (45%).

Potential barriers to addressing overweight and obesity before pregnancy include poor uptake of routine prepregnancy health activities, inaccurate self-categorisation of weight, unsuccessful weight loss attempts and inadequate advice regarding prepregnancy weight loss.