Gestational weight gain in a multi-ethnic sample of pregnant women from Counties Manukau Health, Auckland, New Zealand.

Aim: High and low gestational weight gain (GWG) adversely affects perinatal outcomes, and impacts long-term maternal and child health. Our aim is to report i) GWG categories by 2009 Institute of Medicine guidelines in the multi-ethnic population in Counties Manukau Health, ii) demographic factors and iii) adverse perinatal outcomes associated with high and low GWG.

Method: Women with singleton pregnancy and weight recorded at ≤20 weeks and again in the third trimester comprised the study population. GWG categories (weight gain per week) were defined as low, normal or high. Maternal characteristics and pregnancy outcomes were compared between GWG categories.

Results: Study population comprised 604 women: 39.7% Pacific, 19.9% Māori, 21.5% European. 70.5% were overweight or obese, and 65.1% lived in the highest deprivation decile areas. 70.7% had high, 16.1% had normal and 13.2% had low GWG. Pacific [OR 3.58 (95% CI 1.82, 7.03)] had increased odds of high GWG and Para 2/3+ had reduced odds of high GWG [OR 0.50 (95% CI 0.26, 0.99), OR 0.36 (95% CI 0.17, 0.74) respectively]. Low GWG was associated with increased SGA [ OR 2.48 (95% CI 1.11, 6.44)] and with GDM [OR 2.74 (95%CI 1.06, 8.79)]. We demonstrated a linear association between GWG and birthweight with 126g (95% CI: 90g, 162g) increase per 250g increase in weekly GWG.

Conclusion: The majority of participants had high GWG, which is clinically relevant as this was associated with increased infant weight, with potential to perpetuate intergenerational obesity. The association between low GWG and GDM may reflect care in the GDM clinic.