RESUMEN
The anthropogenic climate change may impact pregnancy outcomes. Rather than ambient temperature, we aimed to use a composite bioclimatic metric (Universal Thermal Climate Index, UTCI) to identify critical susceptible windows for the associations between bioclimatic exposure and hypertensive disorders of pregnancy (HDPs) risk. Daily UTCI exposure from 12 weeks of preconception through pregnancy was linked to 415,091 singleton pregnancies between 1st January 2000 and 31st December 2015 in Western Australia. Adjusted weekly-specific and cumulative odds ratios (ORs) and 95% confidence intervals (CIs) of gestational hypertension and preeclampsia were estimated with distributed lag non-linear and standard non-linear logistic regressions. Exposures from early pregnancy to week 30 were associated with greater odds of HDPs with critical susceptible windows, particularly elevated at the 1st (10.2 °C) and 99th (26.0 °C) exposure centiles as compared to the median (14.2 °C). The most elevated ORs were 1.07 (95% CI 1.06, 1.08) in weeks 8-18 for gestational hypertension and 1.10 (95% CI 1.08, 1.11) in weeks 11-16 for preeclampsia for the 99th exposure centile. Cumulative exposures associated with HDPs with relatively higher but less precise ORs. The effects of high exposure to HDPs indicated sociodemographic inequalities. The identified critical periods and subpopulations could benefit from climate-related interventions.
RESUMEN
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.