This prospective cohort study is nested within the LIMIT
randomised trial, evaluating the effect of an antenatal dietary
and lifestyle intervention for women who are overweight or
obese [31]. The methodology of the LIMIT randomised trial has
been described in detail previously [31]. The LIMIT trial
recruited women with a live singleton pregnancy and a BMI
of 25 kg/m2 between 10 and 20 weeks’ gestation, at the time
of their first antenatal appointment. All women provided
written informed consent to participate. Eligible, consenting
women were randomised using a central telephone randomisation
service, and a randomisation schedule prepared by
non-clinical research staff with balanced variable blocks.
Women were randomised to the Dietary and Lifestyle Advice
Group or the Standard Care Group. Women in the latter group
continued to receive their pregnancy care according to local
hospital guidelines and comprise the cohort for this current
analysis. Women who are overweight or obese receiving
antenatal care according to local hospital guidelines are not
routinely provided with lifestyle and behavioural advice.
Women were recruited from public maternity hospitals across
the South Australian metropolitan area (specifically, Women’s
and Children’s Hospital, Lyell McEwin Hospital, and Flinders
Medical Centre). Ethics approval was obtained from all sites.
At the time of trial entry, all women had their height and
weight measured, and BMI calculated. Women were then
categorised according to their BMI as either overweight (BMI
25.0–29.9 kg/m2
) or obese (BMI 30.0 kg/m2
), with obesity
further classified into subclass 1 (BMI 30.0–34.9 kg/m2
), subclass
2 (BMI 35.0–39.9 kg/m2
), and subclass 3 (BMI 40.0 kg/m2
),
utilising World Health Organisation criteria [3