Reproducibility of Bioelectrical Impedance Analysis in Pregnancy and the Association of Body Composition with the Risk of Gestational Diabetes: A Substudy of MUMS Cohort

Introduction. Bioelectrical impedance analysis (BIA) is a rapid and noninvasive method of body composition analysis; however, reproducibility between BIA instruments in pregnancy is uncertain. Adverse maternal body composition has been linked to pregnancy complications including gestational diabetes mellitus (GDM). This study aimed to evaluate the reproducibility of three BIA instruments in pregnancy and analyse the relationship between the body composition and the GDM risk. Methods. A prospective cohort (n = 117) of women with singleton pregnancies participating in the Microbiome Understanding in Maternity Study (MUMS) at St. George Hospital, Sydney, Australia. Anthropometric measurements and BIA body composition were measured at ≤13 weeks (T1), 20–24 weeks (T2), and 32–36 weeks (T3) of gestation. Body fat percentage (BFP), total body water (TBW), and impedance were estimated by three BIA instruments: Bodystat 1500, RJL Quantum III, and Tanita BC-587. GDM status was recorded after 75 g oral glucose tolerance test was performed at 28 weeks or earlier. Agreement between BIA instruments was assessed using Bland–Altman analysis. Logistic regression modelling explored associations of BFP with GDM. Results. Method comparison reproducibility between Bodystat and RJL was stronger than between Bodystat and Tanita for both BFP and TBW% at all three time points. RJL overestimated BFP on average by 3.3% (p<0.001), with limits of agreement within ±5% for all trimesters. Average BFP was not significantly different between Tanita and Bodystat although limits of agreement exceeded ±5%. GDM diagnosis was independently associated with increased BFP in T1 (adjusted OR 1.117 per 1% increase; 95% CI 1.020–1.224; p=0.017) and in T2 (adjusted OR 1.113 per 1% increase; 95% CI 1.010–1.226; p=0.031) and with Asian ethnicity in all models (OR 7.4–8.1). Conclusion. Reproducibility amongst instruments was moderate; therefore, interchangeability between instruments, particularly for research purposes, cannot be assumed. In this cohort, GDM risk was modestly associated with increasing BFP and strongly associated with Asian ethnicity

What women want if they were to have another baby: the Australian Birth Experience Study (BESt) cross-sectional national survey

Objectives To explore if Australian women would do anything differently if they were to have another baby.Design and setting The Birth Experience Study (BESt) online survey explored pregnancy, birth and postnatal experiences for women who had given birth during 2016–2021 in Australia.Participants In 2021, 8804 women responded to the BESt survey and 6101 responses to the open text responses to the survey question ‘Would you do anything different if you were to have another baby?’ were analysed using inductive content analysis.Results A total of 6101 women provided comments in response to the open text question, resulting in 10 089 items of coding. Six categories were found: ‘Next time I'll be ready’ (3958, 39.2%) described how women reflected on their previous experience, feeling the need to better advocate for themselves in the future to receive the care or experience they wanted; ‘I want a specific birth experience’ (2872, 28.5%) and ‘I want a specific model of care’ (1796, 17.8%) highlighted the types of birth and health provider women would choose for their next pregnancy. ‘I want better access’ (294, 2.9%) identified financial and/or geographical constraints women experience trying to make choices for birth. Two categories included comments from women who said ‘I don’t want to change anything’ (1027, 10.2%) and ‘I don’t want another pregnancy’ (142, 1.4%). Most women birthed in hospital (82.9%) and had a vaginal birth (59.2%) and 26.7% had a caesarean.Conclusion Over 85% of comments left by women in Australia were related to making different decisions regarding their next birth choices. Most concerningly women often blamed themselves for not being more informed. Women realised the benefits of continuity of care with a midwife. Many women also desired a vaginal birth as well as better access to birthing at home

Relationship between Diet Quality and Maternal Stool Microbiota in the MUMS Australian Pregnancy Cohort

Dietary intake during pregnancy may influence the antenatal microbiome, which is proposed to impact maternal and infant health during the pregnancy and beyond. The aim of this sub-study was to examine associations between dietary intake and microbiota diversity during pregnancy using whole metagenomic sequencing and examine associations in low-risk versus high-risk pregnancies, as well as complicated versus uncomplicated pregnancies. Pregnancy data were analysed from women participating in the MUMS cohort study in Sydney, Australia (women followed from trimester 1 of pregnancy to 1-year postpartum), who had dietary intake data at either trimester 1 or 3, assessed using the Australian Eating Survey, and a matched stool sample (n = 86). Correlations of microbial alpha diversity with dietary intake data were determined using the repeated-measures correlation, rmcorr, in R. In the combined cohort, no associations were found between diet quality or diet composition and microbial alpha diversity or beta diversity. However, trends in our analysis suggested that dietary intake of specific macro- and micronutrients may influence microbial diversity differently, depending on particular pregnancy conditions. Our findings suggest that dietary intake during pregnancy may have a variable influence on the maternal microbiota, unique to the individual maternal pregnancy phenotype. More research is needed to disentangle these associations

Differences in the Active Endometrial Microbiota across Body Weight and Cancer in Humans and Mice

Obesity is a risk factor for endometrial cancer. The aim of this study was to determine whether actively replicating microbiota in the endometrium differ between obese vs. lean and cancer vs. benign states. We performed 16S rRNA amplicon sequencing on endometrial tissues from lean and obese women with and without endometrial cancer, and lean and obese mice. Results displayed human endometrial microbiota clustered into three community types (R = 0.363, p = 0.001). Lactobacillus was dominant in community type 1 (C1) while community type 2 (C2) had high levels of Proteobacteria and more cancer samples when compared to C1 (p = 0.007) and C3 (p = 0.0002). A significant increase in the prevalence of the C2 community type was observed across body mass index and cancer (&chi;2 = 14.24, p = 0.0002). The relative abundance of Lactobacillus was lower in cancer samples (p = 0.0043), and an OTU with 100% similarity to Lactobacillus iners was enriched in control samples (p = 0.0029). Mouse endometrial microbiota also clustered into three community types (R = 0.419, p = 0.001) which were not influenced by obesity. In conclusion, obesity and cancer are associated with community type prevalence in the human endometrium, and Lactobacillus abundance is associated with normal uterine histologies in humans and mice