Background: SARS-CoV-2 specific antibodies exist in human milk expressed by lactating parents after vaccination. In the existing research, the effects of vaccine types on human milk are inconsistent.
Research aim: This study aims to perform a systematic review and meta-analysis of the existing observational studies to compare the positive rates of SARS-CoV-2 specific antibodies in human milk according to mRNA and adenovector-based vaccination.
Methods: PubMed, Web of Science, Elsevier Science Direct and Cochrane Library databases were systematically searched for relevant articles published from December 30, 2019 to February 15, 2023. Observational studies were considered eligible provided they reported data on SARS-CoV-2 specific antibodies in human milk. The risk of bias in non-randomized studies of interventions (ROBINS-I) tool, the Newcastle-Ottawa Scale (NOS), and the Agency for Healthcare Research and Quality (AHRQ) were used to assess risk of bias. Seven studies, including 511 lactating participants, were included in this review and meta-analysis.
Results: The positive rate of SARS-CoV-2 IgA is higher in mRNA vaccine groups than in adenovector-based vaccine groups (OR = 4.80, 95% CI [3.04, 7.58], p < 0.001). The positive rate of SARS-CoV-2 IgG was higher in mRNA vaccines than in adenovector-based vaccines.
Conclusions: Compared to adenovector-based vaccines, mRNA vaccines present a higher positivity rate of IgA and IgG in human milk after vaccination. In other words, mRNA vaccinations may offer breastfed children a higher level of protection than adenovector-based vaccinations. Further high-quality data is still required to substantiate these findings.
Background: German-speaking mothers have breastfeeding rates below the international breastfeeding recommendations. Previous research has found that breastfeeding self-efficacy is an important and modifiable predictor of breastfeeding outcomes, thus improving breastfeeding rates. The Breastfeeding Self-Efficacy Scale-Short Form (BSES-SF) is used in many countries to assess maternal breastfeeding self-efficacy. This instrument has not been available in German.
Research aims: To translate the BSES-SF into German and assess its psychometric properties among breastfeeding mothers up to 12 weeks postpartum.
Methods: This cross-sectional study was conducted online with 355 breastfeeding mothers recruited from breastfeeding groups through Facebook. The BSES-SF was translated into German using forward and back-translation. To test reliability, item-total characteristics, including Cronbach's alpha, were examined. We used principal component analysis, as well as known-groups comparisons for evaluating construct validity, and examined the relationship between breastfeeding self-efficacy and demographic variables.
Results: The mean age of participants was 32.4 years (SD = 4.32). The Cronbach's alpha coefficient was .88 and corrected item-total correlations ranged between .37 and .73. Principal components analysis yielded one component with factor loadings >.40 and an eigenvalue of 5.62, which explained 40% of the total variance. In addition, known group comparisons provided further evidence for construct validity. There was no significant difference in BSES-SF scores in terms of demographic and obstetrics characteristics.
Conclusion: Our results provide evidence that the German version of the BSES-SF is a reliable and valid tool for measuring breastfeeding self-efficacy among mothers in German-speaking countries.
Pediatricians need to be knowledgeable to adequately carry out their role in the support of breastfeeding, so assessing their knowledge of breastfeeding is vitally important. There are not English language validated questionnaires for pediatricians in the literature; however, in Spanish and Portuguese, there is the Breastfeeding Knowledge Survey (ECoLa, derived from Encuesta de Conocimientos en Lactancia). Our goal is to translate the ECoLa into English. The original survey consisted of true/false questions, including one with an image of a breastfeeding baby, multiple-choice questions featuring clinical cases, and two open-ended short questions. We used a translation approach that incorporated both forward and backward translations and a multidisciplinary committee to evaluate the translation process. During translation, four Spanish versions and seven English versions were considered prior to consensus approval of the final survey. The intraclass correlation coefficient between the English questionnaire and the original Spanish version was 0.85 (95% CI [0.60, 0.95]). A sample of 51 participants completed the survey, resulting in a Cronbach's alpha of 0.78 for the English version (95% CI [0.70, 0.86]). The Breastfeeding Knowledge Survey is now accessible under a Creative Commons license, permitting its free re-use.