Lifestyle Intervention and Prevention of Gestational Diabetes Mellitus

A Randomized Controlled Trial Examining the Effectiveness of a Lifestyle Intervention in Reducing Gestational Diabetes Mellitus in High Risk Chinese Pregnant Women in Hong Kong

The number of women with gestational diabetes mellitus (GDM) had been increasing. Maternal GDM has a great impact on both the health of the mothers and the offspring. Antenatal lifestyle interventions, in particular dietary intervention appear to be feasible to improve maternal GDM and weight gain. To the best of our knowledge, there has been no such trial examining the feasibility of a lifestyle intervention in pregnant women in Hong Kong. Therefore, we plan to conduct a randomized controlled trial comparing a lifestyle modification program (LMP) in early pregnancy and the usual antenatal care in high risk Chinese pregnant women in Hong Kong. Intervention group subjects (n=110) will participate in a dietitian-led LMP including dietary and exercise component from the first antenatal (AN) booking to 24 weeks gestation. 110 women in the control group will receive routine hospital antenatal care. The primary endpoint will be the prevalence of GDM measured using a 75 g oral glucose tolerance test at 24-28 weeks gestation. The secondary endpoints will be the proportion of infant born with large for gestational age (>=95th percentile of the customized birth weight) and macrosomia (>=4 kg at birth). The intervention group involves dietary and exercise advice and monitoring. No drug or invasive procedure is involved. The control group will receive routine antenatal care and will be provided with an educational pamphlet on diet and exercise during pregnancy.

On top of the usual care, subjects in the intervention will receive a lifestyle intervention that will be delivered by experienced registered dietitian and exercise specialist. There will be 5 face-to-face dietitian consultations, 2 telephone dietitian consultations and at least one face-to-face exercise specialist consultation. The exercise consultation will be normally scheduled on the same day of the face-to-face dietitian consultation.

Women will have their first AN booking visit generally on or before 12 week gestation. For women who are primigravida, their AN visit appointments will be set at every 6 weeks before 24 weeks, every 4 weeks between 24-28 weeks, and every 2 weeks after 28 weeks. For women who are multigravida, the corresponding schedules will be set at every 6 weeks before 24 weeks, every 4 weeks between 24-36 weeks, and every 2 weeks after 36 weeks. Body weight of the pregnant woman will be monitored by nurses and basic nutrition advice will be briefly given by nurses in case she is slightly overweight. They will be provided with an educational pamphlet on diet and exercise during pregnancy. They will also be offered optional antenatal classes which subjected to quotas availability.

On top of the usual care, subjects in the intervention will receive a lifestyle intervention that will be delivered by experienced registered dietitian and exercise specialist. There will be 5 face-to-face dietitian consultations, 2 telephone dietitian consultations and at least one face-to-face exercise specialist consultation. The exercise consultation will be normally scheduled on the same day of the face-to-face dietitian consultation.

Inclusion Criteria: Chinese origin Reside normally in Hong Kong Singleton pregnancy Gestational age <= 12 weeks at the time of recruitment Could speak and understand Chinese Fulfill at least one of the following criteria for high risk of GDM at the time of recruitment based on the update hospital protocol implemented since 1st May 2014 Maternal age >= 35 years old at expected date of confinement. Prior history of GDM or birth of child >= 4 kg Pre-pregnant BMI or BMI at 1st trimester >= 25 kg/m2 Family history of diabetes at 1st degree relatives Willing to give informed written consent and follow the study procedures Exclusion Criteria: Concurrent participation in any clinical trial or study With renal, liver or thyroid dysfunction, cognitive impairment, or any other indication of a major medical or psychological illness, as judged by the investigators as ineligible to participate the study Multiple pregnancies Pre-existing DM With physical restriction that prevents from exercising Substance abuse

Chan RS, Tam WH, Ho IC, Kwan MW, Li LS, Sea MM, Woo J. Randomized trial examining effectiveness of lifestyle intervention in reducing gestational diabetes in high risk Chinese pregnant women in Hong Kong. Sci Rep. 2018 Sep 14;8(1):13849. doi: 10.1038/s41598-018-32285-6.