Background
Maternal obesity and excessive gestational weight gain (GWG) are prevalent in Australia and associated with an increased risk of birth complications, gestational diabetes and caesarean delivery.

Aim
To assess the effect of a pilot dietetic intervention in supporting the achievement of appropriate GWG.

Materials and methods
Pregnant women with a pre‐pregnancy body mass index (BMI) ≥ 35 kg/m2 (n = 174, mean BMI 40.6 ± 4.3 kg/m2) were referred for individual assessment and dietary counselling conducted by a dietitian with subsequent reviews. Education was based on the Australian Guide to Healthy Eating (AGTHE), encouraged nutritional adequacy and promoted GWG in line with current Institute of Medicine (IOM) guidelines.

Results
The intervention was associated with a significant reduction (P = 0.00) in gestational weight gain (3.57 ± 5.37 kg) when compared to previous pregnancies (14.31 ± 11.23 kg). Women who attended three or more appointments gained significantly less weight compared with those who attended the initial assessment only (P < 0.05). Rates of caesarean delivery and macrosomia were lower among participants compared to obese populations in comparable studies. Conclusions Dietetic intervention in obese pregnant women can assist in achieving and limiting gestational weight gain to within current IOM guidelines and reduced rates of gestational diabetes and caesarean section.