COVID-19 mRNA vaccine-mediated antibodies in human breast milk and their association with breast milk microbiota composition.

Newborns can acquire immunological protection to SARS-CoV-2 through vaccine-conferred antibodies in human breast milk. However, there are some concerns around lactating mothers with regards to potential short- and long-term adverse events and vaccine-induced changes to their breast milk microbiome composition, which helps shape the early-life microbiome. Thus, we sought to explore if SARS-CoV-2 mRNA vaccine could change breast milk microbiota and how the changes impact the levels of antibodies in breast milk. We recruited 49 lactating mothers from Hong Kong who received two doses of BNT162b2 vaccine between June 2021 and August 2021. Breast milk samples were self-collected by participants pre-vaccination, one week post-first dose, one week post-second dose, and one month post-second dose. The levels of SARS-CoV-2 spike-specific IgA and IgG in breast milk peaked at one week post-second dose. Subsequently, the levels of both antibodies rapidly waned in breast milk, with IgA levels returning to baseline levels one month post-second dose. The richness and composition of human breast milk microbiota changed dynamically throughout the vaccination regimen, but the abundances of beneficial microbes such as Bifidobacterium species did not significantly change after vaccination. Additionally, we found that baseline breast milk bacterial composition can predict spike-specific IgA levels at one week post-second dose (Area Under Curve: 0.72, 95% confidence interval: 0.58-0.85). Taken together, our results identified specific breast milk microbiota markers associated with high levels of IgA in the breast milk following BNT162b2 vaccine. Furthermore, in lactating mothers, BNT162b2 vaccines did not significantly reduce probiotic species in breast milk.

Feasibility and effectiveness of WhatsApp online group on breastfeeding by peer counsellors: a single-blinded, open-label pilot randomized controlled study.

INTRODUCTION: With mobile technologies becoming more advanced and accessible, mobile health (mHealth) has been incorporated in delivering timely and convenient breastfeeding support. However, its feasibility and potential efficacy remain to be examined. Therefore, the primary objective of this study is to assess the feasibility and acceptability of an online instant messaging peer support group for breastfeeding. The secondary objective is to evaluate the effect of the intervention on breastfeeding outcomes. METHODS: A pilot randomized controlled trial was conducted. A total of 33 primiparous women were recruited in the antenatal clinic at a public hospital in Hong Kong between March and April 2021. They were randomized to receive either standard care (n = 18) or standard care and receive peer-group support in an online instant messaging app (n = 15). Participants received telephone follow-up for up to six months postpartum or until they stopped breastfeeding. After completing the study, six participants in the intervention group were interviewed to understand their perceptions of the intervention. RESULTS: This pilot study shows that online messaging peer support group is feasible and acceptable to women. In total, 54.4% of the eligible women agreed to participate, and 97.0% completed the follow-up. Participants perceived that providing peer support through instant messaging app is appropriate. It serves as a channel for the participants to ask questions and obtain information. Furthermore, meetings of the peer supporters and group members can be held to enhance the effectiveness of the intervention. In addition, no significant differences were found in any and exclusive breastfeeding rates, breastfeeding attitude, and breastfeeding self-efficacy between the two groups. CONCLUSIONS: This study shows that online messaging peer support group is feasible and acceptable. A full-scale study should be conducted to understand the effect of the online instant messaging peer support group on breastfeeding outcomes. TRIAL REGISTRATION: The study protocol is registered on Clinicaltrial.gov (NCT04826796) on 1 April 2021.

Validating the use of the revised childbirth experience questionnaire in Hong Kong.

OBJECTIVE: To evaluate the psychometric properties of the traditional Chinese version of the Childbirth Experience Questionnaire (CEQ 2.0) and assess the childbirth experiences of Chinese women. METHODS: A cross-sectional survey was conducted in Hong Kong from July 2020 to February 2021. In total, 975 mothers, who could read traditional Chinese and gave birth in 2020 or 2021, were included in the analysis. Data were fitted into the model proposed by the original developers using the confirmatory factor analysis. The data were then randomly split into training and validation sets for exploratory and confirmatory factor analyses. Childbirth experiences were assessed. Factor structure, internal construct validity, internal consistency, and known-group validity were assessed. RESULTS: The originally proposed CEQ2.0 model showed a poor fit. An exploratory factor analysis identified a revised four-factor model (CEQ2.0-R) on a randomly split sample, which showed a satisfactory fit (CFI=0.912; TLI=0.884; SRMR=.053; RMSEA=0.072) on the other split sample. The revised scale comprised 13 items and four domains: (1)"Own capacity" (6 items), (2) "General support" (3 items), (3) "Perceived safety" (2 items), and (4) "Professional support" (2 items). CEQ2.0-R showed high internal construct validity and reliability. It can differentiate between participants with different characteristics, including parity, oxytocin augmentation, and companionship during labour. The childbirth experiences of the participants were merely positive, and participants reported that more support from midwives is needed. CONCLUSIONS: CEQ2.0-R can adequately describe the childbirth experiences of women in Hong Kong. The questionnaire is easy to be administer and can be used to assess several domains of the childbirth experiences. It may be useful to evaluate the aspects of support needed during childbirth.

Exposure to baby-friendly hospital practices and mothers' achievement of their planned duration of breastfeeding.

BACKGROUND: Both breastfeeding intentions and exposure to baby-friendly hospital practices were found to be associated with a longer duration of breastfeeding. This study aims to examine the effect of exposure to baby-friendly hospital practices on mothers' achievement of their planned duration of breastfeeding. METHODS: A total of 1011 mother-newborn pairs from the postnatal units of four public hospitals in Hong Kong were recruited. Sociodemographic data and breastfeeding intention data were collected via self-report questionnaires during the postnatal hospitalization and exposure to Baby-Friendly hospital practices were assessed through hospital records and maternal self-report. Breastfeeding status after hospital discharge was assessed through telephone follow-up for up to 12 months postnatal, or until participants were no longer breastfeeding. RESULTS: Only 55% (n = 552) of study participants achieved their intended duration of breastfeeding. Participants with higher socioeconomic status, previous breastfeeding experience, and those who had lived in Hong Kong for less than 5 years, were more likely to achieve their planned duration of breastfeeding. Among baby-friendly hospital practices, feeding only breast milk during the hospitalization and providing information about breastfeeding support on discharge were associated with participants' achieving their individual breastfeeding intentions. After adjustment, when compared with women who experienced onebaby-friendly practice, participants who experienced six baby-friendly hospital practices were significantly more likely to achieve their planned duration of breastfeeding (adjusted odds ratio = 8.45, 95% confidence interval 3.03-23.6). CONCLUSIONS: Nearly half of participants did not achieve their planned breastfeeding duration. Exposure to baby-friendly hospital practices, especially in-hospital exclusive breastfeeding and providing breastfeeding support information upon hospital discharge may help more mothers to achieve their individual breastfeeding goals.