Associations between endometriosis and adverse pregnancy and perinatal outcomes: a population-based cohort study.

PURPOSE: To examine the association between endometriosis and adverse pregnancy and perinatal outcomes (preeclampsia, placenta previa, and preterm birth). METHODS: A population-based retrospective cohort study was conducted among 468,778 eligible women who contributed 912,747 singleton livebirths between 1980 and 2015 in Western Australia (WA). We used probabilistically linked perinatal and hospital separation data from the WA data linkage system's Midwives Notification System and Hospital Morbidity Data Collection databases. We used a doubly robust estimator by combining the inverse probability weighting with the outcome regression model to estimate adjusted risk ratios (RR) and 95% confidence intervals (CIs). RESULTS: There were 19,476 singleton livebirths among 8874 women diagnosed with endometriosis. Using a doubly robust estimator, we found pregnancies in women with endometriosis to be associated with an increased risk of preeclampsia with RR of 1.18, 95% CI 1.11-1.26, placenta previa (RR 1.59, 95% CI 1.42-1.79) and preterm birth (RR 1.45, 95% CI 1.37-1.54). The observed association persisted after stratified by the use of Medically Assisted Reproduction, with a slightly elevated risk among pregnancies conceived spontaneously. CONCLUSIONS: In this large population-based cohort, endometriosis is associated with an increased risk of preeclampsia, placenta previa, and preterm birth, independent of the use of Medically Assisted Reproduction. This may help to enhance future obstetric care among this population.

Probiotic supplementation in neonates and long-term gut colonisation: A systematic review of randomised controlled trials.

BACKGROUND: Probiotic supplementation in the neonatal period results in improved gut colonisation with probiotic bacteria in the short term. There is limited information on the long-term sustainability of this colonisation. AIMS: To evaluate whether oral probiotic supplementation in the neonatal period results in sustained gut colonisation with probiotic bacteria at or beyond 6 months after its cessation. METHODS: A systematic review of neonatal probiotic randomised controlled trials (RCTs) that reported on the stool microbiota during post-discharge follow-up was carried out using guidelines of the Cochrane neonatal group. RESULTS: Four RCTs (n = 605 infants) were included in the review. The studies were heterogeneous in case selection, choice of probiotics, duration of supplementation, timing and the method of stool microbial analysis. Three RCTs (n = 471) showed the presence of intestinal probiotic bacteria at 6-12 months. The overall certainty of evidence was very low in view of small sample size, heterogeneity and identification only to the genus/species level. CONCLUSION: Low certainty of evidence suggests that probiotic supplementation in the neonatal period may result in sustained gut colonisation 6-12 months post-cessation, but not at 24 months. Adequately powered, well-designed RCTs with strain-specific assays are needed in this area.

Association between interpregnancy interval and hypertensive disorders of pregnancy: Effect modification by maternal age.

BACKGROUND: Short and long interpregnancy intervals (IPI) are associated with increased risk of hypertensive disorders of pregnancy, yet whether this association is modified by maternal age remains unclear. OBJECTIVES: To examine if the association between IPI and hypertensive disorders of pregnancy varies by maternal age at birth prior to IPI. METHODS: We conducted a population-based cohort study of all mothers who had their first two (n = 169 896) consecutive births in Western Australia (WA) between 1980 and 2015. We estimated the risk of preeclampsia and gestational hypertension for 6 to 60 months of IPI according to maternal age at birth prior to IPI (<20 years, 20-24, 25-29, 30-34 and ≥35 years). We modelled IPI using restricted cubic splines and reported adjusted relative risk (RRs) with 95% CI at 6, 12, 24, 36, 48 and 60 months, with 18 months as reference. RESULTS: The risk of preeclampsia was increased at longer IPIs (60 months) compared to 18 months for mothers 35 years or older (RR 2.19, 95% confidence interval (CI) 1.14, 4.18) and to a lesser extent for mothers 30- to 34 years old (RR 1.43, 95% CI 1.10, 1.84). Compared to 18 months, the risk of preeclampsia was lower at 12 months of IPI for mothers younger than 20 years (RR 0.74, 95% CI 0.57, 0.96), but not for mothers 35 years or older (RR 0.62, 95% CI 0.36, 1.07). There was insufficient evidence for increased risk of hypertensive disorders of pregnancy at shorter IPIs of <18 months for mothers of all ages. CONCLUSIONS: Our findings challenge the "one size fits all" recommendation for an optimal IPI, and a more tailored approach to family planning counselling may be required to improve health.

Interpregnancy interval and hypertensive disorders of pregnancy: A population-based cohort study.

BACKGROUND: Despite extensive research on risk factors and mechanisms, the extent to which interpregnancy interval (IPI) affects hypertensive disorders of pregnancy in high-income countries remains unclear. OBJECTIVES: To examine the association between IPI and hypertensive disorders of pregnancy in a high-income country setting using both within-mother and between-mother comparisons. METHODS: A retrospective population-based cohort study was conducted among 103 909 women who delivered three or more consecutive singleton births (n = 358 046) between 1980 and 2015 in Western Australia. We used conditional Poisson regression with robust variance, matching intervals of the same mother and adjusted for factors that vary within-mother across pregnancies, to investigate the association between IPI categories (reference 18-23 months), and the risk of hypertensive disorders of pregnancy. For comparison with previous studies, we also applied unmatched Poisson regression (between-mother analysis). RESULTS: The incidence of preeclampsia and gestational hypertension during the study period was 4%, and 2%, respectively. For the between-mother comparison, mothers with intervals of 6-11 months had lower risk of preeclampsia with adjusted relative risk (RR) 0.92 (95% confidence interval [CI] 0.85, 0.98) compared to reference category of 18-23 months. With the within-mother matched design, we estimated a larger effect of long IPI on risk of preeclampsia (RR 1.29, 95% CI 1.18, 1.42 for 60-119 months; and RR 1.30, 95% CI 1.10, 1.53 for intervals ≥120 months) compared to 18-23 months. Short IPIs were not associated with hypertensive disorders of pregnancy. CONCLUSIONS: In our cohort, longer IPIs were associated with increased risk of preeclampsia. However, there was insufficient evidence to suggest that short IPIs (<6 months) increase the risks of hypertensive disorders of pregnancy.

Influence of preterm birth on the association between gestational diabetes mellitus and childhood developmental vulnerability: a causal mediation analysis.

BACKGROUND: Epidemiological studies examining the direct and indirect effects of gestational diabetes mellitus (GDM) on offspring early childhood developmental vulnerability are lacking. Therefore, the aims of this study were to estimate the direct and indirect effects of GDM (through preterm birth) on early childhood developmental vulnerability. METHODS: We conducted a retrospective population-based cohort study on the association between gestational diabetes mellitus and early childhood developmental vulnerability in children born in Western Australia (WA) using maternal, infant and birth records from the Midwives Notification, Hospitalizations, Developmental Anomalies, and the Australian Early Development Census (AEDC) databases. We used two aggregated outcome measures: developmentally vulnerable on at least one AEDC domain (DV1) and developmentally vulnerable on at least two AEDC domains (DV2). Causal mediation analysis was applied to estimate the natural direct (NDE), indirect (NIE), and total (TE) effects as relative risks (RR). RESULTS: In the whole cohort (n = 64,356), approximately 22% were classified as DV1 and 11% as DV2 on AEDC domains. Estimates of the natural direct effect suggested that children exposed to GDM were more likely to be classified as DV1 (RR = 1.20, 95% CI: 1.10-1.31) and DV2 (RR = 1.34, 95% CI: 1.19-1.50) after adjusting for potential confounders. About 6% and 4% of the effect of GDM on early childhood developmental vulnerability was mediated by preterm birth for DV1 and DV2, respectively. CONCLUSION: Children exposed to gestational diabetes mellitus were more likely to be developmentally vulnerable in one or more AEDC domains. The biological mechanism for these associations is not well explained by mediation through preterm birth.

The impact of armed conflicts on HIV treatment outcomes in Sub-Saharan Africa: a systematic review and meta-analysis.

BACKGROUND: Despite the fact that Sub-Saharan Africa bears a disproportionate burden of armed conflicts and HIV infection, there has been inadequate synthesis of the impact of armed conflict on HIV treatment outcomes. We summarized the available evidence on the impact of armed conflicts on HIV treatment outcomes in Sub-Saharan Africa from 2002 to 2022. METHODS: We searched four databases; MEDLINE, PubMed, CINHAL, and Scopus. We also explored grey literature sources and reviewed the bibliographies of all articles to identify any additional relevant studies. We included quantitative studies published in English from January 1, 2002 to December 30, 2022 that reported on HIV treatment outcomes for patients receiving antiretroviral therapy (ART) in conflict and post-conflict areas, IDP centers, or refugee camps, and reported on their treatment outcomes from sub-Saharan Africa. Studies published in languages other than English, reporting on non-ART patients and reporting on current or former military populations were excluded. We used EndNote X9 and Covidence to remove duplicates, extracted data using JBI-MAStARI, assessed risk of bias using AHRQ criteria, reported results using PRISMA checklist, and determined Statistical heterogeneity using Cochran Q test and Higgins I2, R- and RevMan-5 software were used for meta-analysis. RESULTS: The review included 16 studies with participant numbers ranging from 102 to 2572. Lost To Follow-Up (LTFU) percentages varied between 5.4% and 43.5%, virologic non-suppression rates ranged from 25 to 33%, adherence rates were over 88%, and mortality rates were between 4.2% and 13%. A pooled meta-analysis of virologic non-suppression rates from active conflict settings revealed a non-suppression rate of 30% (0.30 (0.26-0.33), I2 = 0.00%, p = 0.000). In contrast, a pooled meta-analysis of predictors of loss to follow-up (LTFU) from post-conflict settings identified a higher odds ratio for females compared to males (1.51 (1.05, 2.17), I2 = 0%, p = 0.03). CONCLUSION: The review highlights a lack of research on the relationship between armed conflicts and HIV care outcomes in SSA. The available documents lack quality of designs and data sources, and the depth and diversity of subjects covered.

Probiotic Supplementation in the Neonatal Age Group and the Risk of Hospitalisation in the First Two Years: A Data Linkage Study from Western Australia.

BACKGROUND: Probiotic supplementation in preterm neonates is standard practice in many centres across the globe. The impact of probiotic supplementation in the neonatal age group on the risk of hospitalisation in infancy has not been reported previously. METHODS: Infants born < 32 + 6 weeks of gestation in Western Australia were eligible for inclusion. We conducted a retrospective cohort study comparing data from before probiotic supplementation (Epoch 1: 1 December 2008-30 November 2010, n = 1238) versus after (Epoch 2: 1 June 2012-30 May 2014, n = 1422) on the risks of respiratory- and gastrointestinal infection-related hospitalisation. A subgroup analysis of infants born < 28 weeks of gestation was analysed separately for similar outcomes. RESULTS: Compared to Epoch 1, an 8% reduction in incidence of hospitalisation up to 2 years after birth was observed in Epoch 2 (adjusted incidence rate ratio (IRR) of 0.92; 95% confidence interval (CI); 0.87-0.98), adjusted for gestational age, smoking, socioeconomic status, and maternal age. The rate of hospitalisation for infants born < 28 weeks of gestation was comparable in epochs 1 and 2. CONCLUSION: Infants exposed to probiotic supplementation in the neonatal period experience a reduced risk of hospitalisation in the first two years after discharge from the neonatal unit.

The effects of pre-eclampsia on social and emotional developmental vulnerability in children at age five in Western Australia: A population data linkage study.

BACKGROUND: It is important to explore factors that may hinder early childhood development in AEDC Emotional Maturity and Social Competence domains as these underpin the foundation for health, well-being, and productivity over the life course. No previous study has examined whether, or to what extent, preeclampsia increases the risk of developmental vulnerability in social and emotional domains in early childhood. METHODS: We conducted a retrospective population-based cohort study on the association between preeclampsia and childhood developmental vulnerability in emotional maturity and social competence domains in children born in Western Australia in 2009, 2012 and 2015. We obtained records of births, developmental anomalies, midwives notifications and hospitalisations. These data were linked to the Australian Early Development Census (AEDC), from which developmental vulnerability in emotional maturity and social competence domains at a median age of 5 years was ascertained. Causal relative risks (RR) were estimated with doubly robust estimation. RESULTS: A total of 64,391 mother-offspring pairs were included in the final analysis. For the whole cohort, approximately 25 % and 23 % of children were classified as developmentally vulnerable or at-risk on AEDC emotional maturity and social competence domains, respectively. Approximately 2.8 % of children were exposed in utero to preeclampsia. Children exposed to preeclampsia were more likely to be classified as developmentally vulnerable or at-risk on the emotional maturity (RR = 1.19, 95%CI:1.11-1.28) and social competence domains (RR = 1.22, 95 % CI:1.13-1.31). CONCLUSION: Children exposed to pre-eclampsia in utero were more likely to be developmentally vulnerable in emotional maturity and social competence domains in this cohort. Our findings provide new insights into the harmful effect of preeclampsia on childhood developmental vulnerability.

Diabetic and hypertensive disorders following early pregnancy loss: a systematic review and meta-analysis.

Background: Spontaneous and induced abortions are common outcomes of pregnancy. There is inconsistent evidence of an association between early pregnancy loss and subsequent diabetic and hypertensive disorders in women. This systematic review and meta-analysis evaluated evidence on the risk of the subsequent development of pregnancy and non-pregnancy related diabetic and hypertensive disorders in women who experienced an early pregnancy loss. Methods: Systematic searches were conducted in seven electronic databases (CINAHL Plus, Ovid/EMBASE, Ovid/MEDLINE, ProQuest, PubMed, Scopus, and Web of Science) from inception to 22nd December 2023. Studies were included if they reported an exposure of spontaneous abortion (SAB), induced abortion (IA) or recurrent pregnancy loss (RPL) with an outcome of gestational diabetes mellitus, pre-eclampsia, gestational hypertension, and non-pregnancy related diabetic and hypertensive disorders. Risk of bias was assessed using Risk of Bias Instrument for Non-Randomized Studies of Exposures (ROBINS-E). Random effects meta-analysis was used to pool odds of developing diabetic and hypertensive disorders following an early pregnancy loss. This study is registered with PROSPERO (CRD42022327689). Findings: Of 20,176 records, 60 unique articles were identified for full-text review and 52 met the inclusion criteria, representing a total population of 4,132,895 women from 22 countries. Thirty-five studies were suitable for meta-analysis, resulting in a pooled odds ratio (OR) of 1.44 (95% confidence interval (CI) 1.23-1.68) for gestational diabetes mellitus following a prior SAB and a pooled OR of 1.06 (95% CI 0.90-1.26) for pre-eclampsia following a prior SAB. RPL increased the odds of developing pre-eclampsia (OR 1.37 95% CI 1.05-1.79). There was no association between IA and diabetic and hypertensive disorders. Interpretation: A prior SAB was associated with increased odds of gestational diabetes mellitus, but not pre-eclampsia. However, women who experienced RPL had an increased risk of subsequent pre-eclampsia. Future research is required to establish evidence for an association between early pregnancy loss with non-pregnancy related diabetic and hypertensive disorders. Funding: National Health and Medical Research Council.

The effect of maternal prenatal tobacco smoking on offspring academic achievement: A systematic review and meta-analysis.

BACKGROUND: Previous epidemiological studies examining the prospective association between maternal prenatal tobacco smoking and offspring academic achievement have reported conflicting results. Therefore, this systematic review and meta-analysis was conducted to examine the magnitude and consistency of association reported by those studies. METHODS: This systematic review and meta-analysis was guided by the PRISMA protocol. Relevant epidemiological studies on the topic were extracted from four main databases (PubMed/Medline, Embase, PsycINFO, and Scopus). The Newcastle-Ottawa Scale (NOS) was used to appraise the methodological quality of the included studies. We conducted a narrative assessment of the studies that did not report effect estimates. Inverse variance-weighted random effect meta-analysis was used to combine studies reporting effect sizes to estimate pooled adjusted odds ratio with 95% confidence intervals (95% CI). The review was prospectively registered in PROSPERO (CRD42022350901). RESULTS: Nineteen observational studies, published between 1973 and 2021 with a total of 1.25 million study participants were included in the final review. Of these, fifteen studies (79 %) reported reduced academic achievement in offspring exposed to maternal prenatal tobacco smoking. The eight primary studies (sample size = 723,877) included in the meta-analysis together suggested a 49 % higher risk of reduced academic achievement in offspring exposed to maternal prenatal tobacco smoking when compared to non-exposed offspring (Pooled odds ratio = 1.49, 95 % CI:1.17-1.91). CONCLUSION: Our review found a positive association between maternal prenatal tobacco smoking and offspring reduced academic achievement. However, variation in the adjustment of potential confounders and significant heterogeneity across included studies limited more conclusive inference. Mechanistic studies to identify causal pathways and specific academic impacts are needed to inform targeted developmental programs to assist child learning and academic performance.

Average treatment effect of maternal prenatal tobacco smoking on offspring developmental vulnerability in early childhood.

BACKGROUND: Early childhood developmental vulnerability has been closely related to the predictors of relatively good health, social and educational outcomes later in adulthood. However, the impacts of prenatal tobacco exposure on childhood developmental vulnerability have been rarely examined. Further, a few of the studies that have investigated maternal prenatal tobacco smoking and child developmental vulnerability have reported mixed results and there are currently no published estimates derived from causal epidemiological methods. METHODS: We conducted a retrospective population-based cohort study on the association between maternal prenatal tobacco smoking and developmental vulnerability in children born in Western Australia (WA). De-identified individual-level maternal, infant and birth records were obtained from the Midwives Notification System (MNS), a statutory record of all births in WA. WA register for Developmental Anomalies (WARDA) were also obtained from the WA Data Linkage. Records on early childhood developmental vulnerability at the median age of 5 years were obtained from the Australian Early Development Census (AEDC). We used a doubly robust estimator to estimate the causal effects. RESULTS: Complete data were available for 64,558 mothers-children's pairs. Approximately 16% of children were exposed to maternal prenatal tobacco smoking. Children exposed to maternal prenatal tobacco smoking were more likely to be classified as developmentally vulnerable/at-risk on the physical health and wellbeing (RR = 1.40, 95%CI:1.36-1.45), social competence (RR = 1.42, 95%CI: 1.38-1.47), emotional maturity (RR = 1.34, 95%CI:1.30-1.39), language and cognitive skills (RR = 1.50, 95%CI:1.45-1.54), and communication skills and general knowledge (RR = 1.37, 95%CI:1.33-1.42) domains. CONCLUSION: Maternal prenatal exposure to tobacco may influence early childhood developmental vulnerability. Early intervention to quit tobacco smoking before becoming pregnant could potentially reduce later childhood developmental vulnerability on multiple domains.

Factors Predicting Secondary Respiratory Morbidity Following Early-Life Respiratory Syncytial Virus Infections: Population-Based Cohort Study.

Background: The association between early-life respiratory syncytial virus (RSV) infections and later respiratory morbidity is well established. However, there is limited evidence on factors that influence this risk. We examined sociodemographic and perinatal factors associated with later childhood respiratory morbidity requiring secondary care following exposure to a laboratory-confirmed RSV episode in the first 2 years. Methods: We used a probabilistically linked whole-of-population-based birth cohort including 252 287 children born in Western Australia between 2000 and 2009 with follow-up to the end of 2012. Cox proportional hazards models estimated adjusted hazard ratios (aHRs) of the association of various risk factors with the first respiratory episode for asthma, wheezing, and unspecified acute lower respiratory infection beyond the age of 2 years. Results: The analytic cohort included 4151 children with a confirmed RSV test before age 2 years. The incidence of subsequent respiratory morbidity following early-life RSV infection decreased with child age at outcome (highest incidence in 2-<4-year-olds: 41.8 per 1000 child-years; 95% CI, 37.5-46.6), increased with age at RSV infection (6-<12-month-olds: 23.6/1000 child-years; 95% CI, 19.9-27.8; 12-<24-month-olds: 22.4/1000 child-years; 95% CI, 18.2-22.7) and decreasing gestational age (50.8/1000 child-years; 95% CI, 33.5-77.2 for children born extremely preterm, <28 weeks gestation). Risk factors included age at first RSV episode (6-<12 months: aHR, 1.42; 95% CI, 1.06-1.90), extreme prematurity (<28 weeks: aHR, 2.22; 95% CI, 1.40-3.53), maternal history of asthma (aHR, 1.33; 95% CI, 1.04-1.70), and low socioeconomic index (aHR, 1.76; 95% CI, 1.03-3.00). Conclusions: Our results suggest that in addition to preterm and young infants, children aged 12-<24 months could also be potential target groups for RSV prevention to reduce the burden of later respiratory morbidities associated with RSV.

Determining the true incidence of seasonal respiratory syncytial virus-confirmed hospitalizations in preterm and term infants in Western Australia.

Respiratory syncytial virus contributes to significant global infant morbidity and mortality. We applied a previously developed statistical prediction model incorporating pre-pandemic RSV testing data and hospital admission data to estimate infant RSV-hospitalizations by birth month and prematurity, focused on infants aged <1 year. The overall predicted RSV-hospitalization incidence rates in infants <6 months were 32.7/1,000 child-years (95 % CI: 31.8, 33.5) and 3.1/1,000 child-years (95 % CI: 3.0, 3.1) in infants aged 6-<12 months. Predicted RSV-hospitalization rates for infants aged <6 months were highest for infants born in April/May. Predicted rates for preterm infants born 29-32 weeks gestation were highest in March-May, whereas infants born >33 weeks had peak RSV-hospitalization rates from May-June, similar to late preterm or term births. RSV-hospitalization rates in the pre-pandemic era were highly seasonal, and seasonality varied with degree of prematurity. Accurate estimates of RSV-hospitalization in high-risk sub-groups are essential to understand preventable burden of RSV especially given the current prevention landscape.

Achieving reductions in the unmet need for contraception with postpartum family planning counselling in Ethiopia, 2019-2020: a national longitudinal study.

BACKGROUND: An unmet need for contraception is associated with unintended pregnancy and adverse maternal and childhood outcomes. Family planning counselling is linked with reduced unmet need for contraception. However, evidence is lacking in Ethiopia on the impact of integrated family planning counselling on the unmet need for contraception. This study aimed to examine the association between family planning counselling and the unmet need for contraception in Ethiopia. METHODS: We used community-based prospective cohort study data from a nationally representative survey conducted by Performance Monitoring for Action Ethiopia between 2019 and 2020. Women who had received three maternal and child health (MCH) services (n = 769) - antenatal care (ANC), facility delivery and child immunisation - were included in this study. The primary exposure variable was family planning counselling provided during the different MCH services. A weighted modified Poisson regression model was used to estimate the adjusted relative risk (aRR) of the unmet need for contraception. RESULTS: The prevalence of family planning counselling during ANC, prior to discharge, and child immunisation was 22%, 28%, and 28%, respectively. Approximately one-third (34%) of the women had an unmet need for contraception. Family planning counselling prior to discharge from the facility was associated with reductions in the unmet need for contraception (aRR 0.88; 95% CI 0.67, 1.16). The risk of unmet need for contraception was 31% (aRR 0.69; 95% CI 0.48, 0.98) less likely among women who had received family planning counselling during child immunisation services. However, family planning counselling during ANC was associated with an increased unmet need for contraception (aRR 1.24; 95% CI 0.93, 1.64). CONCLUSION: Strongest evidence was observed for moderate associations between reductions in the unmet need for contraception and family planning counselling during the provision of child immunisation services in Ethiopia.

The influence of birth outcomes and pregnancy complications on interpregnancy interval: a quantile regression analysis.

PURPOSE: To ascertain whether adverse pregnancy outcomes at first pregnancy influence subsequent interpregnancy intervals (IPIs) and whether the size of this effect varies with IPI distribution METHODS: We included 251,892 mothers who gave birth to their first two singletons in Western Australia, from 1980 to 2015. Using quantile regression, we investigated whether gestational diabetes, hypertension, or preeclampsia in the first pregnancy influenced IPI to subsequent pregnancy and whether effects were consistent across the IPI distribution. We considered intervals at the 25th centile of the distribution as 'short' and the 75th centile as 'long'. RESULTS: The average IPI was 26.6 mo. It was 0.56 mo (95% CI: 0.25-0.88 mo) and 1.12 mo (95% CI: 0.56 - 1.68 mo) longer after preeclampsia, and gestational hypertension respectively. There was insufficient evidence to suggest that the association between previous pregnancy complications and IPI differed by the extent of the interval. However, associations with marital status, race/ethnicity and stillbirth contributed to either shortening or prolonging IPIs differently across the distribution of IPI. CONCLUSION: Mothers with preeclampsia and gestational hypertension had slightly longer subsequent IPIs than mothers whose pregnancies were not complicated by these conditions. However, the extent of the delay was small (<2 mo).

Bias in the association between advanced maternal age and stillbirth using left truncated data.

Restriction to analysis of births that survive past a specified gestational age (typically 20 weeks gestation) leads to biased exposure-outcome associations. This bias occurs when the cause of restriction (early pregnancy loss) is influenced by both the exposure and unmeasured factors that also affect the outcome. The aim of this study is to estimate the magnitude of bias resulting from left truncated data in the association between advanced maternal age and stillbirth. We simulated data for the causal pathway under a collider-stratification mechanism. Simulation parameters were based on an observed birth cohort from Western Australia and a range of plausible values for the prevalence of early pregnancy loss, unmeasured factor U and the odds ratios for the selection effects. Selection effects included the effects of maternal age on early pregnancy loss, U on early pregnancy loss, and U on stillbirth. We compared the simulation scenarios to the observed birth cohort that was truncated to pregnancies that survived beyond 20 gestational weeks. We found evidence of marginal downward bias, which was most prominent for women aged 40 + years. Overall, we conclude that the magnitude of bias due to left truncation is minimal in the association between advanced maternal age and stillbirth.

The role of family planning counselling during maternal and child health services in postpartum modern contraceptive uptake in Ethiopia: A national longitudinal study.

Family planning counselling can help improve the postpartum modern contraceptive uptake. However, studies in Ethiopia indicate inconsistent effects of integrated family planning counselling on postpartum modern contraceptive uptake. This study aimed to determine the extent of family planning counselling and its role in improving postpartum contraceptive uptake among women in Ethiopia. We used the Performance Monitoring for Action (PMA) Ethiopia panel survey data, a community-based prospective cohort study. Randomly selected pregnant women were recruited at the baseline interview and followed by six weeks and six months postpartum. A weighted generalised linear model fitted with a Poisson distribution and a log link function was used to estimate the adjusted relative risk (aRR) and 95% Confidence Interval (CI) of modern contraceptive uptake. The coverages of family planning counselling provision during ANC, prior to discharge and child immunisation were 20%, 27% and 23%, respectively. The modern contraceptive uptakes by six weeks and six months postpartum were 18% and 36%, respectively. Family planning counselling prior to discharge from the facility was associated with increased modern contraceptive uptake by six weeks (aRR 1.25; 95% CI 0.94, 1.65) and six months postpartum periods (aRR 1.07; 95% CI 0.90, 1.27). Moreover, women who received family planning counselling during child immunisation were 35% more likely to use modern contraceptives by six months postpartum (aRR 1.35;95% CI 1.12, 1.62). However, counselling during ANC visits was not associated with modern contraceptive uptake by either six weeks or six months postpartum. A significant proportion of women had missed the opportunity, and the postpartum modern contraceptive uptake was low. Despite these, family planning counselling prior to discharge from the facility and during child immunisation improved the postpartum modern contraceptive uptake. However, our finding revealed insufficient evidence that family planning counselling during ANC is associated with postpartum modern contraceptive uptake.

Developing a prediction model to estimate the true burden of respiratory syncytial virus (RSV) in hospitalised children in Western Australia.

Respiratory syncytial virus (RSV) is a leading cause of childhood morbidity, however there is no systematic testing in children hospitalised with respiratory symptoms. Therefore, current RSV incidence likely underestimates the true burden. We used probabilistically linked perinatal, hospital, and laboratory records of 321,825 children born in Western Australia (WA), 2000-2012. We generated a predictive model for RSV positivity in hospitalised children aged < 5 years. We applied the model to all hospitalisations in our population-based cohort to determine the true RSV incidence, and under-ascertainment fraction. The model's predictive performance was determined using cross-validated area under the receiver operating characteristic (AUROC) curve. From 321,825 hospitalisations, 37,784 were tested for RSV (22.8% positive). Predictors of RSV positivity included younger admission age, male sex, non-Aboriginal ethnicity, a diagnosis of bronchiolitis and longer hospital stay. Our model showed good predictive accuracy (AUROC: 0.87). The respective sensitivity, specificity, positive predictive value and negative predictive values were 58.4%, 92.2%, 68.6% and 88.3%. The predicted incidence rates of hospitalised RSV for children aged < 3 months was 43.7/1000 child-years (95% CI 42.1-45.4) compared with 31.7/1000 child-years (95% CI 30.3-33.1) from laboratory-confirmed RSV admissions. Findings from our study suggest that the true burden of RSV may be 30-57% higher than current estimates.

Interbirth interval and maternal anaemia in 21 sub-Saharan African countries: A fractional-polynomial analysis.

BACKGROUND: Maternal anaemia is a global public health problem contributing to adverse maternal and perinatal outcomes. In addition to other risk factors, interbirth interval has been identified as a potentially modifiable risk factor of maternal anaemia. However, the current evidence for the association between interbirth interval and maternal anaemia remains inconclusive. Hence, this study examined the association between the interbirth interval and maternal anaemia in sub-Saharan Africa. METHODS: We conducted a multinational cross-sectional study of interbirth interval (time between two singleton live births) and maternal anaemia (haemoglobin levels < 12 g/dl for non-pregnant women, < 11 g/dl for pregnant women) for 21 sub-Saharan African countries using the most recent nationally representative Demographic and Health Surveys, 2010-2017. A weighted multivariable fractional polynomial function was used to estimate the non-linear relationship between interbirth interval and maternal anaemia, considering interbirth interval as a continuous variable and adjusting for potential confounders. Analyses were stratified by reproductive classification (non-pregnant and pregnant women). RESULTS: There were 81,693 women included in the study (89.2% non-pregnant, 10.8% pregnant). Of all women, 32.2% were in their postpartum period. Overall, 36.9% of women had anaemia (36.0% of non-pregnant and 44.3% of pregnant women). Of the participants, 15% had a short interbirth interval (<24 months), and 16% had a long interbirth interval (≥ 60 months). We found that both short and longer interbirth intervals were associated with an increased risk of maternal anaemia in a dose-response fashion. Relatively a lower risk of maternal anaemia was observed between 24 and 40 months of interbirth intervals. CONCLUSIONS: Our findings suggest that both short and longer interbirth intervals were associated with an increased risk of maternal anaemia in sub-Saharan Africa.

Diabetic and Hypertensive Disorders Following Miscarriage: A Protocol for Systematic Review and Meta-Analysis.

(1) Background: Miscarriages occur in approximately 15-25% of all pregnancies. There is limited evidence suggesting an association between history of miscarriage and the development of diabetic and hypertensive disorders in women. This systematic review aims to collate the existing literature and provide up to date epidemiological evidence on the topic. (2) Methods: We will search CINAHL Plus, Ovid/EMBASE, Ovid/MEDLINE, ProQuest, PubMed, Scopus, Web of Science, and Google Scholar, using a combination of medical subject headings, keywords, and search terms, for relevant articles related to the association between miscarriage and the risk of diabetic and hypertensive disorders. Cross-sectional, case-control, nested case-control, case-cohort, and cohort studies published from inception to April 2022 will be included in the search strategy. Three reviewers will independently screen studies and the risk of bias will be assessed using the Joanna Briggs Institute Critical Appraisal tool. Where the data permit, a meta-analysis will be conducted. (3) Results: The results of this systematic review will be submitted to a peer-reviewed journal for publication. (4) Conclusions: The findings of this systematic review will instigate efforts to manage and prevent reproductive, cardiovascular, and metabolic health consequences associated with miscarriages.