The effects and experience of antenatal human milk expression among Hong Kong Chinese women with gestational diabetes

Abstract

The rising incidence of Gestational Diabetes Mellitus (GDM) poses a global public health challenge, as it is associated with obstetric complications and adverse maternal and infant outcomes. The Chinese population experiences a particularly high incidence of GDM, contributing to breastfeeding challenges and an increased risk of type 2 diabetes for both mothers and children. In Hong Kong, exclusive breastfeeding rates remain low compared to global standards. The Baby-Friendly Hospital Initiative promotes breastfeeding in line with international guidelines, offering significant benefits for women with GDM. To support these efforts, the Gestational Diabetes and Antenatal Milk Expression (GAME) program was developed as a behavioural intervention to promote exclusive breastfeeding. This study evaluated the acceptability, feasibility, and effectiveness of antenatal milk expression (AME) as a breastfeeding intervention. It also explored the perceptions and experiences of Hong Kong Chinese women with GDM. A two-phase mixed-methods design was employed. Phase one involved a pilot Randomized Controlled Trial (RCT) conducted between August and December 2021 at two regional birthing hospitals. Twenty women with GDM planning to breastfeed healthy term singleton infants were randomly assigned to either the intervention group (AME education plus standard care) or the control group (standard care only) at 37 weeks of gestation. Outcomes, including exclusive breastfeeding rates, breastfeeding self-efficacy, and postpartum depressive symptoms, were assessed using intention-to-treat analysis. Quantitative data were analysed using Generalized Linear Mixed Models, and qualitative data underwent reflexive thematic analysis. The feasibility study demonstrated successful recruitment with 77% (n=20) agreeing to participate in the study. High intervention compliance was found with 90% of participants practising AME after education. Five qualitative interviews revealed positive experiences with the intervention. In the second phase, conducted between January 2022 and December 2023, a larger mixed-methods study was undertaken. Women were invited to participate during antenatal visits. A total of 246 participants were randomly assigned to intervention and control groups, with 215 completing the follow-up. At 4 weeks postpartum, exclusive breastfeeding rates were significantly higher in the intervention group compared to the control group (adjusted difference = 0.17, 95% CI: 0.04 to 0.31, p = 0.014). At 8 weeks postpartum, the intervention group reported significantly lower depressive symptoms (adjusted difference = 1.41, 95% CI: 0.41 to 2.40, p = 0.006). Subgroup analyses indicated greater reductions in depressive symptoms among multiparous women and those undergoing elective caesarean sections. Nineteen semi-structured interviews identified four themes: 1) Challenges and strategies in AME practice, 2) Support and confidence building, 3) Breast preparation and facilitating breastfeeding, and 4) Health beliefs and program advocacy. Participants reported positive experiences and perceptions, recommending the program to other women. This study highlights the potential of integrating AME into breastfeeding interventions for women with GDM. The GAME program was desirable, improved exclusive breastfeeding rates, enhanced breastfeeding self-efficacy, and reduced postpartum depressive symptoms. Scaling up this intervention in Hong Kong could empower midwives to strengthen breastfeeding support for Chinese women with GDM in Hong Kong. Further research is warranted to confirm its long-term efficacy and applicability in other populations.