Introduction
Depression and anxiety are the most common mental health conditions
during pregnancy, with approximately 12% and 13% of women experiencing
them, respectively.1 Antenatal depression and anxiety
are associated with increased risk of post-partum depression, and poor
cognitive and emotional development in the child.2South Asian (Indian, Pakistani and Bangladeshi) women are more
susceptible to depression and anxiety compared to White
women.3
There is evidence of a significant association between mental health
conditions during pregnancy and maternal obesity. A meta-analysis
published in 2014 found odds of antenatal depression and anxiety
increased by 43% and 30%, respectively, in women with obesity compared
to women of recommended BMI.4 The included studies
were predominately from high-income countries (53 out of 62 studies), of
which two focused on ethnic-minorities (African American and
Hispanic);5,6 none focused on South Asian women. A
systematic review7 investigating the effects of
maternal anthropometrics on pregnancy outcomes in South Asians did not
identify any studies on mental health conditions, further highlighting
the lack of published data in this field.
In addition to the increased risk of mental health conditions among
South Asian women, they also carry an increased risk of maternal
obesity. In the UK, half of pregnant women enter pregnancy with a BMI in
the overweight or obese range.8 Evidence suggests that
South Asian women have the highest odds of first trimester obesity
compared to White British women,9 and an increased
risk of obesity-related complications, e.g. Gestational Diabetes
Mellitus (GDM)7 during pregnancy at a lower BMI than
White British women. The World Health Organisation (WHO) reflects this
in their BMI criteria, where the categories for overweight and obesity
are lower in South Asian groups (23-27.49 kg/m2 and ≥
27.5 kg/m2 respectively)7 compared
with the general population criteria (25-29.9 kg/m2and ≥30 kg/m2).10 The National
Institute of Health and Care Excellence (NICE) guidelines have
recommended the use of these lower WHO thresholds to identify and treat
South Asian individuals with obesity-related
illnesses;11 however, this is not reflected in
pregnancy guidelines.
Given the increased risk for both obesity and mental health conditions
in South Asian women, the aim of this study was to address the current
research gap by investigating the association between antenatal
depression and anxiety and early pregnancy BMI within and between South
Asian and White British women, using data from the Born in Bradford
(BiB) cohort.