Assessment of evidence on reported non-genetic risk factors of congenital heart defects: the updated umbrella review

BACKGROUND

Congenital heart defect (CHD) is the leading cause of birth defects globally, which results in a great disease burden. It is still imperative to detect the risk factors of CHD. This umbrella review aimed to comprehensively summarize the evidence and grade the evidence of the associations between non-genetic risk factors and CHD.

METHODS

Databases including Medline, Embase, Web of Science, Cochrane Library, and four Chinese databases were searched from inception to 18 Jan 2022. The reference lists of systematic reviews (SR) and meta-analyses (MA) were screened, which aimed to explore the non-genetic risk factors of CHD. Subsequently, titles and abstracts of identified records and full texts of selected SR/MA were screened by two independent reviewers based on predefined eligibility criteria. A priori developed extraction form was used to abstract relative data following the PRISMA 2020 and MOOSE guidelines. The risk of bias was assessed with the AMSTAR2 instrument. Data were synthesized using fixed-effects and random-effects meta-analyses, respectively. Finally, the evidence on the association of non-genetic risk factors and CHD was graded using Ioannidis's five-class evidence grade.

RESULTS

A total of 56 SRs, encompassing 369 MAs, were identified. The risk factors included relative factors on air pollution, reproductive-related factors, parental age and BMI, parental life habits, working and dwelling environment, maternal drug exposure, and maternal disease. Based on AMSTAR2 criteria, only 16% (9/56) of SRs were classified as "Moderate". One hundred and two traceable positive association MAs involving 949 component individual studies were included in further analysis and grading of evidence. Family genetic history, number of abortions, maternal obesity, especially moderate or severe obesity, decoration materials, harmful chemicals, noise during pregnancy, folic acid supplementation, SSRIs, SNRIs, any antidepressants in the first trimester, maternal DM (including both PGDM and GDM), and gestational hypertension were convincing and highly suggestive factors for CHD. After sensitivity analyses based on cohort studies, some grades of evidence changed.

CONCLUSION

The present umbrella review will provide evidence-based information for women of childbearing age before or during pregnancy to prevent CHD. In addition, sensitivity analysis based on cohort studies showed the changed evidence levels. Therefore, future SR/MA should concern the sensitivity analysis based on prospective birth cohort studies and case-control studies.

Learning from the report of the independent medicines and medical devices safety review: "first do no harm"

This is a review of the learning points from the Independent Medicines and Medical Devices Safety Review,¹ chaired by Baroness Julia Cumberlege CBE DL. This system-wide review was initiated by the then Secretary of State for Health and Social Care, following patient-led campaigns. It looked at how the "healthcare system reacted as a whole, and how that response can be made more robust, speedy and appropriate".We aim to highlight the learning points for doctors in Obstetrics and Gynaecology as these are relevant to our current practice and future changes in our healthcare system. These are: Aims of the review: why it was initiated and how it was conductedOverarching themes and missed opportunities to prevent avoidable harmThree clinical scenarios: their histories, issues and adverse events associated with their use and the current response in Scotland The hormone pregnancy test - PrimodosThe anti-epileptic drug - sodium valproateSurgical mesh for prolapse & incontinenceThe recommendations made by the review and implementation guidanceResponses to the review, such as apologies issued by BSUG²/BAUS³/RCOG,⁴ and compensations schemes such as the Scottish scheme as recommended by the review.

The rates of major malformations after gestational exposure to isotretinoin: a systematic review and meta-analysis

Objective

Isotretinoin is among the most notorious human teratogens, documented originally as causing up to 30% of malformations. This systematic review and meta-analysis aimed to evaluate the rates of major malformation (MM) among isotretinoin-exposed pregnant women over the years through a systematic review and meta-analysis.

Methods

Eligible studies were searched and identified using various databases. Single-arm meta-analysis and meta-analysis of odd ratios among controlled studies were performed using Review Manager version 5.3.

Results

Ten eligible studies that combined 2,783 isotretinoin-exposed women were included in our study. The rate of MM weighted for the sample size was 15%. Three studies that included an unexposed comparison group were eligible for the meta-analysis. The pooled odds ratio of MM for isotretinoin-exposed women was 3.76. After 2006, the pooled odds ratio of MM for isotretinoin exposure was significantly lower at 1.04.

Conclusion

The current rate of MM in isotretinoin-exposed women was substantially lower after 2006.

Environmental Risk Factors and Congenital Heart Disease: An Umbrella Review of 165 Systematic Reviews and Meta-Analyses With More Than 120 Million Participants

Background: The etiology of congenital heart disease (CHD) has been extensively studied in the past decades. Therefore, it is critical to clarify clear hierarchies of evidence between types of environmental factors and CHD. Methods: Electronic searches in PubMed, Embase, Web of Science, Cochrane database were conducted from inception to April 20, 2020 for meta-analyses investigating the aforementioned topic. Results: Overall, 41 studies including a total of 165 meta-analyses of different environmental factors and CHD were examined, covering a wide range of risk factors. The summary random effects estimates were significant at P < 0.05 in 63 meta-analyses (38%), and 15 associations (9%) were significant at P < 10^-6. Of these meta-analyses, eventually one risk factor (severe obesity; relative risk: 1.38, 95% confidence interval: 1.30-1.47) had significant summary associations at P < 10^-6, included more than 1,000 cases, had 95% prediction intervals excluding the null value, and were not suggestive of large heterogeneity (I ² < 50%), small-study effects (P-value for Egger's test > 0.10), or excess significance (P > 0.10). Eight associations (5%) (including maternal lithium exposure, maternal obesity, maternal alcohol consumption, and maternal fever) had results that were significant at P < 10^-6, included more than 1,000 cases, and had 95% prediction intervals excluding the null value (highly suggestive). Conclusion: This umbrella review shows that many environmental factors have substantial evidence in relation to the risk of developing CHD. More and better-designed studies are needed to establish robust evidence between environmental factors and CHD. Systematic Review Registration: [PROSPERO], identifier [CRD42020193381].

Early pregnancy maternal progesterone administration alters pituitary and testis function and steroid profile in male fetuses

Maternal exposure to increased steroid hormones, including estrogens, androgens or glucocorticoids during pregnancy results in chronic conditions in offspring that manifest in adulthood. Little is known about effects of progesterone administration in early pregnancy on fetal development. We hypothesised that maternal early pregnancy progesterone supplementation would increase fetal progesterone, affect progesterone target tissues in the developing fetal reproductive system and be metabolised to other bioactive steroids in the fetus. We investigated the effects of progesterone treatment during early pregnancy on maternal and fetal plasma progesterone concentrations, transcript abundance in the fetal pituitary and testes and circulating steroids, at day 75 gestation, using a clinically realistic ovine model. Endogenous progesterone concentrations were lower in male than female fetuses. Maternal progesterone administration increased male, but not female, fetal progesterone concentrations, also increasing circulating 11-dehydrocorticosterone in male fetuses. Maternal progesterone administration altered fetal pituitary and testicular function in ovine male fetuses. This suggests that there may be fetal sex specific effects of the use of progesterone in early pregnancy, and highlights that progesterone supplementation should be used only when there is clear evidence of efficacy and for as limited time as necessary.