This trial will assess the impact of a culturally tailored, personalized nutrition intervention on glycemic response to an oral glucose load (as measured by the area-under-the curve glucose) in high-risk pregnancies of South Asian women. The intervention targets two at-risk individuals: mother and infant, "breaking the cycle" of maternal gestational dysglycemia, excess infant adiposity and insulin resistance, and CVD in both mother and baby. The findings of this study will be important in guiding future evidence-based recommendations and public health policies to manage gestational glycemia in pregnant women at risk of GDM.

The DESI-GDM study is a randomized study to assess the impact of a culturally tailored, personalized nutrition intervention on glycemic response to an oral glucose load in high-risk pregnancies of South Asian women. Eligible South Asian pregnant women will be randomized to intervention or control.

South Asians (SA), people whose ancestors are from India, Pakistan, Bangladesh, or Sri Lanka, are the largest non-white ethnic group in Canada, and are at high risk of type 2 diabetes mellitus (T2DM) and early cardiovascular disease (CVD). SA women have at least double the risk of gestational diabetes (GDM) of white European women, and risk factors for future T2DM in the offspring including higher birthweight, more adipose tissue, and reduced insulin sensitivity, are more common in SA infants of mothers with GDM than infants born to mothers without GDM.

Building on our findings from the South Asian prospective birth cohort (START), which identified diet as a key modifiable risk factor for GDM, we have developed a dietary intervention. The women we spoke with expressed a desire to learn more about healthy eating to prevent diabetes during pregnancy and were keen to use mobile health technology.

The objectives of this trial among pregnant women of South Asian descent are to:

1. Evaluate the effectiveness of a culturally-tailored personalized nutrition intervention delivered by a trained health coach to improve blood sugar levels in South Asian women to a greater extant than usual dietary advice.
2. Evaluate the effectiveness of a culturally-tailored personalized nutrition intervention delivered by a trained health coach to pregnant South Asian women in the reduction of the incidence of gestational diabetes mellitus to a greater extent than usual dietary advice.

The findings of this study will be important in guiding future evidence-based recommendations and public health policies to manage gestational glycemia in pregnant women at risk of GDM.

Inclusion Criteria:

• pregnant

• South Asian ancestry

• gestational week 12-18

• singleton pregnancy

• at least 2 of the following:

  1. age > 29
  2. low diet quality (assessed with a short diet questionnaire)
  3. family history of type 2 diabetes in first-degree relative
  4. gestational diabetes during a previous pregnancy
  5. pre-pregnancy body-mass-index ≥23.17

Exclusion Criteria:

• type 1 or type 2 diabetes
• high blood pressure (>140 mm Hg systolic or >90 mm Hg diastolic)
• poor understanding of English
• unwillingness to modify diet
• at high risk of adverse pregnancy outcomes other than gestational diabetes (e.g. twins or higher-order multiples, use of fertility treatment(s), pre-existing hypertension, history of placenta previa or pre-term birth)
• enrollment in another study
• does not have a smartphone
• not willing to walk
• excessive nausea and/or vomiting

Request for data will be assessed on a case by case basis.

Those assessing the primary and secondary clinical outcomes are masked to treatment assignment.