Queensland Family Cohort: a study protocol

Maternal physical activity and sitting time and its association with placental morphology and blood flow during gestation: Findings from the Queensland Family Cohort study

OBJECTIVES

Antenatal exercise is associated with placental morphological alterations, however research in this area is limited. Given the emphasis on the beneficial effects of antenatal exercise, it is important to understand its effect on placental function and the relationship to foetal development. The aim of this study was to investigate the association between physical activity, sitting time, and placental outcomes measured during gestation.

DESIGN

Prospective cohort study.

METHODS

Pregnant women in the Queensland Family Cohort study self-reported physical activity at 24 and 36 weeks of gestation (n = 203) and were categorised into physical activity volume groups of nil-low (0-<500 metabolic equivalent of task·minutes/week), moderate (500-<1000 metabolic equivalent of task·minutes/week), or high-volume activity (≥1000 metabolic equivalent of task·minutes/week). Participants reported average daily sitting time, whereby excessive sitting time was considered as ≥8h/day. Placental stiffness, thickness, and uteroplacental blood flow resistance were measured by ultrasound imaging at each timepoint.

RESULTS

Physical activity volume was not associated with changes to placental morphometrics or uteroplacental blood flow resistance at 24 or 36 weeks of gestation. Excessive sitting time at 36 weeks was associated with greater placental stiffness (p = 0.046), and a lower umbilical artery pulsatility index (p = 0.001).

CONCLUSIONS

Placental tissue stiffness and umbilical artery resistance were altered in late gestation with higher maternal sitting time but not with physical activity volume. Overall, excessive sitting time may be a risk for suboptimal placental function and could be an important focus for antenatal care.

Delivery mode is a larger determinant of infant gut microbiome composition at 6 weeks than exposure to peripartum antibiotics

Background. Previous research has shown that delivery mode can shape infant gut microbiome composition. However, mothers delivering by caesarean section routinely receive prophylactic antibiotics prior to delivery, resulting in antibiotic exposure to the infant via the placenta. Previously, only a small number of studies have examined the effect of delivery mode versus antibiotic exposure on the infant gut microbiome with mixed findings.Objective. We aimed to determine the effect of delivery mode compared to antibiotic use during labour and delivery on the infant and maternal gut microbiome at 6 weeks post-partum.Methodology. Twenty-five mother-infant dyads were selected from the longitudinal Queensland Family Cohort Study. The selected dyads comprised nine vaginally delivered infants without antibiotics, seven vaginally delivered infants exposed to antibiotics and nine infants born by caesarean section with routine maternal prophylactic antibiotics. Shotgun-metagenomic sequencing of DNA from stool samples collected at 6 weeks post-partum from mother and infant was used to assess microbiome composition.Results. Caesarean section infants exhibited decreases in Bacteroidetes (ANCOM-BC q<0.0001, MaAsLin 2 q=0.041), changes to several functional pathways and altered beta diversity (R 2=0.056, P=0.029), while minimal differences due to antibiotic exposure were detected. For mothers, caesarean delivery (P=0.0007) and antibiotic use (P=0.016) decreased the evenness of the gut microbiome at 6 weeks post-partum without changing beta diversity. Several taxa in the maternal microbiome were altered in association with antibiotic use, with few differentially abundant taxa associated with delivery mode.Conclusion. For infants, delivery mode appears to have a larger effect on gut microbiome composition at 6 weeks post-partum than intrapartum antibiotic exposure. For mothers, both delivery mode and intrapartum antibiotic use have a small effect on gut microbiome composition at 6 weeks post-partum.

Dietary supplements, guideline alignment and biochemical nutrient status in pregnancy: Findings from the Queensland Family Cohort pilot study

In high-income nations, multiple micronutrient (MMN) supplementation during pregnancy is a common practice. We aimed to describe maternal characteristics associated with supplement use and daily dose of supplemental nutrients consumed in pregnancy, and whether guideline alignment and nutrient status are related to supplement use. The Queensland Family Cohort is a prospective, Australian observational longitudinal study. Maternal characteristics, nutrient intake from food and supplements, and biochemical nutrient status were assessed in the second trimester (n = 127). Supplement use was reported by 89% of participants, of whom 91% reported taking an MMN supplement. Participants who received private obstetric care, had private health insurance and had greater alignment to meat/vegetarian alternatives recommendations were more likely to report MMN supplement use. Private obstetric care and general practitioner shared care were associated with higher daily dose of supplemental nutrients consumed compared with midwifery group practice. There was high reliance on supplements to meet nutrient reference values for folate, iodine and iron, but only plasma folate concentrations were higher in MMN supplement versus nonsupplement users. Exceeding the upper level of intake for folic acid and iron was more likely among combined MMN and individual supplement/s users, and associated with higher plasma concentrations of the respective nutrients. Given the low alignment with food group recommendations and potential risks associated with high MMN supplement use, whole food diets should be emphasized. This study confirms the need to define effective strategies for optimizing nutrient intake in pregnancy, especially among those most vulnerable where MMN supplement use may be appropriate.

"It's research, our input can grow": identifying health research priorities with Aboriginal and Torres Strait Islander communities-study protocol

BACKGROUND

In Australia, Aboriginal and Torres Strait Islander (Indigenous) families have strong, cohesive, and nurturing cultural practices that contribute to effective family functioning and child rearing. These practices can lead to positive effects on children and communities, and include kinship relations, traditional knowledge systems, collective community focus, respect for Elders contributions, and spirituality. However, poor health and wellbeing outcomes exist across the lifespan for Indigenous Australians. Health programs, services and research that support Indigenous women, babies and their families are a critical investment to improve birthing and health outcomes and impact the life trajectories of Indigenous Australians.

AIM

The Indigenous Health Research Priorities study aims to identify the research priorities for families during the perinatal and early childhood period through a co-designed and collaborative process. This has been led by communities to determine the priorities identified with and for local Indigenous families in Queensland. This paper aims to report on engagement and involvement with Indigenous communities to identity health research priorities for families and presents preliminary findings of the research process including participants' demographic information and feedback on the yarning sessions, as part of the study protocol.

METHODS

The study protocol showcases the Participatory Action Research approach, yarning sessions with clients and staff of three community-controlled health services to date, and Delphi workshop methods to prioritise the health issues identified during the yarns with corresponding communities. The study will undertake qualitative data collection and analysis to identify and report on community and health service research priorities for Indigenous families in Queensland. A short survey was conducted to collect participants' demographic information. A feedback form with five open-ended questions was also administered to collect data on participants' views and satisfaction with the research process.

PRELIMINARY RESULTS

This protocol paper reports on the participant demographic information and feedback on the research process and reactions to participating in the yarning sessions. There have been 12 yarning sessions in Far North Queensland to date. The qualitative analysis of these will be reported on in future, with South East Queensland and further sites to follow. Feedback from 61 community members and health professionals has highlighted they valued sharing stories, being heard, and feeling hopeful. Preliminary findings will be reported.

DISCUSSION

Identification of health research priorities will allow each organisation and region of Queensland to develop research initiatives and the translational outcomes that are a focus for their community members.

Newcastle 1000 (NEW1000) Study: an Australian population-based prospective pregnancy cohort study design and protocol

INTRODUCTION

Multiple cohort studies have been established to investigate the impact of early life factors on development and health outcomes. In Australia the majority of these studies were established more than 20 years ago and, although longitudinal in nature, are inherently susceptible to socioeconomic, environmental and cultural influences which change over time. Additionally, rapid leaps in technology have increased our understanding of the complex role of gene-environment interactions in life course health, highlighting the need for new cohort studies with repeated biological sampling and in-depth phenotype data across the first 1000 days of life from conception.

METHODS AND ANALYSIS

The Newcastle 1000 (NEW1000) Study, based in the regional city of Newcastle, New South Wales, was developed after an extensive consultation process involving 3 years of discussion with key stakeholders and healthcare consumer organisations and seven healthcare consumer workshops. This prospective population-based pregnancy cohort study will recruit 500 families per year for 5 years, providing detailed, longitudinal, multisystem phenotyping, repeated ultrasound measures and serial sample collection to investigate healthcare consumer identified health outcomes of priority. Stage 1 will involve recruitment of pregnant participants and their partners at 14 weeks gestation, with dense phenotype data and biological samples collected at 14, 20, 28 and 36 weeks gestation and serial ultrasound measures at 20, 28, 36 and 40 weeks, with postpartum follow-up at 6 weeks and 6 months. Biological samples will be used for biomarker discovery and sequencing of the genome, transcriptome, epigenome, microbiome and metabolome.

ETHICS AND DISSEMINATION

Ethics approval was obtained from Hunter New England Local Health District Ethics Committee (2020/ETH02881). Outcomes will be published in peer-reviewed journals, disseminated to participants through the NEW1000 website, presented at scientific conferences, and written reports to local, state and national government bodies and key stakeholders in the healthcare system to inform policy and evidence-based practice.

Cohort profile: the BABY1000 pilot prospective longitudinal birth cohort study based in Sydney, Australia

PURPOSE

The health of parents prior to conception, a woman's health during pregnancy and the infant's environment across their first months and years collectively have profound effects on the child's health across the lifespan. Since there are very few cohort studies in early pregnancy, gaps remain in our understanding of the mechanisms underpinning these relationships, and how health may be optimised. 'BABY1000', a pilot prospective longitudinal birth cohort study, aims to (1) identify factors before and during pregnancy and early life that impact longer-term health and (2) assess the feasibility and acceptability of study design to inform future research.

PARTICIPANTS

Participants were based in Sydney, Australia. Women were recruited at preconception or 12 weeks' gestation, and data were collected from them throughout pregnancy and postpartum, their children until the age of 2 years, and dietary information from a partner (if able) at the last study visit. The pilot aimed to recruit 250 women. However, recruitment ceased earlier than planned secondary to limitations from the COVID-19 pandemic and the final number of subjects was 225.

FINDINGS TO DATE

Biosamples, clinical measurements and sociodemographic/psychosocial measures were collected using validated tools and questionnaires. Data analysis and 24-month follow-up assessments for children are ongoing. Key early findings presented include participant demographics and dietary adequacy during pregnancy. The COVID-19 pandemic and associated public health and research restrictions affected recruitment of participants, follow-up assessments and data completeness.

FUTURE PLANS

The BABY1000 study will provide further insight into the developmental origins of health and disease and inform design and implementation of future cohort and intervention studies in the field. Since the BABY1000 pilot was conducted across the COVID-19 pandemic, it also provides unique insight into the early impacts of the pandemic on families, which may have effects on health across the lifespan.

Insufficient Evidence of a Breastmilk Microbiota at Six-Weeks Postpartum: A Pilot Study

Breastmilk is thought to influence the infant gut by supplying prebiotics in the form of human milk oligosaccharides and potentially seeding the gut with breastmilk microbes. However, the presence of a breastmilk microbiota and origins of these microbes are still debated. As a pilot study, we assessed the microbes present in expressed breastmilk at six-weeks postpartum using shotgun metagenomic sequencing in a heterogenous cohort of women who delivered by vaginal (n = 8) and caesarean delivery (n = 8). In addition, we estimated the microbial load of breastmilk at six-weeks post-partum with quantitative PCR targeting the 16S rRNA gene. Breastmilk at six-weeks postpartum had a low microbial mass, comparable with PCR no-template and extraction controls. Microbes identified through metagenomic sequencing were largely consistent with skin and oral microbes, with four samples returning no identifiable bacterial sequences. Our results do not provide convincing evidence for the existence of a breastmilk microbiota at six-weeks postpartum. It is more likely that microbes present in breastmilk are sourced by ejection from the infant's mouth and from surrounding skin, as well as contamination during sampling and processing.

Shear wave velocity measurement of the placenta is not limited by placental location

INTRODUCTION

Ultrasound elastography shows diagnostic promise via the non-invasive determination of placental elastic properties. A limitation is a potential for inadequate measurements from posterior placentae. This study aimed to analyse placental position's influence on measures of shear wave elastography (SWV).

METHODS

SWV elastography measurements were obtained via ultrasound at 24, 28 and 36 weeks gestation from 238 pregnancies. . The placental position was labelled as either anterior, posterior or fundal/lateral. Average SWV measurements (m/s) and the corresponding standard deviations (SD) were used for data analysis.

RESULTS

There was a statistically significant difference between SWV recorded from anterior (1.33 ± 0.19)m/s and posterior (1.39 ± 0.18)m/s placentae (p < 0.001). However, the average sampling depth between these groups was significantly different (3.98 cm vs. 5.38 cm, p < 0.001). There was no statistically significant difference between SWV when measurements were compared at similar depths, regardless of placental location. The addition of placental position to a previously developed mixed-effects model confirmed placental position did not result in improved SWV measurements. In this model, sampling depth remained the best predictor for SWV.

CONCLUSIONS

This study showed that placental position does not influence the accuracy or reliability of SWV.

The social predictors of paternal antenatal mental health and their associations with maternal mental health in the Queensland Family Cohort prospective study

Antenatal depression (AND) affects 1 in 10 fathers, potentially negatively impacting maternal mental health and well-being during and after the transition to parenthood. However, few studies have assessed the social predictors of paternal AND or their possible associations with maternal mental health. We analysed data from 180 couples participating in the Queensland Family Cohort longitudinal study. Both parents completed surveys measuring mental health, relationship quality, social support, and sleep quality at 24 weeks of pregnancy. Mothers also completed the same surveys 6 weeks' postpartum. Antenatal depression, stress, and anxiety were highest among fathers reporting lower social support and higher sleep impairment. Maternal AND, stress, and anxiety were higher among mothers reporting higher physical pain and poor sleep quality. Postnatally, mothers reporting lower social support also reported higher depression, anxiety, stress, and psycho-social well-being. While there were no significant associations between AND among fathers and maternal antenatal or postnatal depression, an exploratory analysis revealed that mothers whose partners reported lower antenatal social support also reported lower postnatal social support and higher postnatal depression. Our findings highlight the importance of including data among fathers to achieve a whole family approach to well-being during the transition to parenthood.

Associations between COVID-19 lockdown and post-lockdown on the mental health of pregnant women, postpartum women and their partners from the Queensland family cohort prospective study

Background

There are very few developed countries where physical isolation and low community transmission has been reported for COVID-19 but this has been the experience of Australia. The impact of physical isolation combined with low disease transmission on the mental health of pregnant women is currently unknown and there have been no studies examining the psychological experience for partners of pregnant women during lockdown. The aim of the current study was to examine the impact of the first COVID-19 lockdown in March 2020 and post lockdown from August 2020 on the mental health of pregnant women or postpartum women and their partners.

Methods

Pregnant women and their partners were prospectively recruited to the study before 24 weeks gestation and completed various questionnaires related to mental health and general wellbeing at 24 weeks gestation and then again at 6 weeks postpartum. The Depression, Anxiety and Stress Scale (DASS-21) and the Edinburgh Postnatal Depression Scale (EPDS) were used as outcome measures for the assessment of mental health in women and DASS-21 was administered to their partners. This analysis encompasses 3 time points where families were recruited; before the pandemic (Aug 2018-Feb 2020), during lockdown (Mar-Aug 2020) and after the first lockdown was over (Sept-Dec 2020).

Results

There was no significant effect of COVID-19 lockdown and post lockdown on depression or postnatal depression in women when compared to a pre-COVID-19 subgroup. The odds of pregnant women or postpartum women experiencing severe anxiety was more than halved in women during lockdown relative to women in the pre-COVID-19 period (OR = 0.47; 95%CI: 0.27–0.81; P = 0.006). Following lockdown severe anxiety was comparable to the pre-COVID-19 women. Lockdown did not have any substantial effects on stress scores for pregnant and postpartum women. However, a substantial decrease of over 70% in the odds of severe stress was observed post-lockdown relative to pre-COVID-19 levels. Partner’s depression, anxiety and stress did not change significantly with lockdown or post lockdown.

Conclusion

A reproductive age population appear to be able to manage the impact of lockdown and the pandemic with some benefits related to reduced anxiety.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04795-9.

Changes in placental elastography in the third trimester - Analysis using a linear mixed effect model

INTRODUCTION

Research into the role of ultrasound elastography to assess compromised placental tissue is ongoing. There is particular interest in evaluating its potential in the investigation of changes associated with uteroplacental dysfunction. To date, there is limited data on how different maternal and fetal considerations, such as advancing gestational age, amniotic fluid Index (AFI) and maternal body mass index (BMI) may influence shear wave velocity (SWV) measurements. This study aimed to evaluate longitudinal changes in SWV throughout gestation and model these changes with other developing fetal and maternal physiological and biological characteristics.

METHODS

The study utilised 238 singleton pregnancies and collected longitudinal data at repeated intervals in the 3rd trimester representing 629 individual data points. Linear mixed model regression analysis was used to identify significant predictors for SWV.

RESULTS

From a total of ten variables selected for modelling, only gestational age, AFI, BMI, and sample depth were found to be significant predictors of placental SWV, and gestational age and AFI were found to have only a minimal impact on SWV.

DISCUSSION

Sophisticated statistical modelling demonstrates that many of the expected maternal and fetal changes in the 3rd trimester have no or minimal impact on placental SWV. Understanding which factors influence placental SWV is essential to ascertain the technique's utility in managing pregnancies complicated by placental dysfunction in the future.