The Use of the Target Trial Approach in Perinatal Pharmacoepidemiology: A Scoping Review Protocol.

Background: Pregnant and postpartum women have been historically excluded from clinical trials, with data on the safety of drugs relying on observational research. Methodological concerns regarding the timing and dosing of medications, data sources, study designs, and methods used for estimating associations are still problematic in observational studies. Answering causal questions is even more complex. Despite the increased interest in emulating target trials using observational data, little is known about this approach in perinatal pharmacoepidemiology. Objective: This scoping review protocol aims to describe the methodology for assessing the available literature concerning emulating target trials for studying outcomes in women exposed to medications in the preconception, perinatal, or postpartum periods. Methods and Analysis: We will follow the methods detailed in the Joanna Briggs Institute reviewer's manual. We will adopt the six-stage framework recommended by Arksey and O'Malley and Levac and others. Web scraping techniques will be used for identifying relevant studies. Two authors will select articles based on the title and abstract, with discrepancies resolved by consensus, by a third reviewer. Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews flow diagram will be presented to reflect the search process. We will use existing statements to identify quality gaps in the current literature. Variables related to the content for perinatal pharmacoepidemiologic research will be included. The Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) will guide the assessment of the target trial emulation (i.e., treatment strategies compared, assignment procedures, follow-up period, outcome, and causal contrasts). Discussion: Data regarding the safety of drugs taken, prior to and during pregnancy and while lactating are lacking and it is necessary to understand how we can answer these questions using rigorous methods in observational research. Through this scoping review, we intend to understand to what extent the target trial approach is being used in perinatal pharmacoepidemiology and provide recommendations to improve its use in this field. Ethics and Dissemination: Secondary data from published scientific articles will be used, not requiring approval by the Research Ethics Committee with human beings. Findings will be submitted to a peer-reviewed journal.

Levothyroxine and the risk of adverse pregnancy outcomes in women with subclinical hypothyroidism: a systematic review and meta-analysis.

BACKGROUND: Levothyroxine replacement therapy may decrease the risk of adverse pregnancy outcomes among women with subclinical hypothyroidism (SCH). The aim of this study is to conduct a systematic review and meta-analysis to examine the risk of adverse pregnancy, perinatal, and early childhood outcomes among women with SCH treated with levothyroxine. METHODS: A systematic literature search was conducted using Ovid-Medline, Ovid-EMBASE, Pubmed (non-Medline), Ebsco-CINAHL Plus with full text and Cochrane Library databases. Randomized controlled studies (RCTs) and observational studies examining the association between treatment of SCH during pregnancy and our outcomes of interest were included. Studies that compared levothyroxine treatment versus no treatment were eligible for inclusion. Data from included studies were extracted and quality assessment was performed by two independent reviewers. RESULTS: Seven RCTs and six observational studies met our inclusion criteria. A total of 7342 individuals were included in these studies. RCTs demonstrated several sources of bias, with lack of blinding of the participants or research personnel; only one study was fully blinded. In the observational studies, there was moderate to serious risk of bias due to lack of adjustment for certain confounding variables, participant selection, and selective reporting of results. Pooled analyses showed decreased risk of pregnancy loss (RR: 0.79; 95% CI: 0.67 to 0.93) and neonatal death (RR: 0.35; 95% CI: 0.17 to 0.72) associated with levothyroxine treatment during pregnancy among women with SCH. There were no associations between levothyroxine treatment and outcomes during labour and delivery, or cognitive status in children at 3 or 5 years of age. CONCLUSION: Treatment of SCH with levothyroxine during pregnancy is associated with decreased risks of pregnancy loss and neonatal death. Given the paucity of available data and heterogeneity of included studies, additional studies are needed to address the benefits of levothyroxine use among pregnant women with SCH.

Hypertensive Disorders of Pregnancy and Medication Use in the 2015 Pelotas (Brazil) Birth Cohort Study.

Hypertensive disorders of pregnancy account for approximately 22% of all maternal deaths in Latin America and the Caribbean. Pharmacotherapies play an important role in preventing and reducing the occurrence of adverse outcomes. However, the patterns of medications used for treating women with hypertensive disorders of pregnancy (HDP) living in this country is unclear. A population-based birth cohort study including 4262 women was conducted to describe the pattern of use of cardiovascular agents and acetylsalicylic acid between women with and without HDP in the 2015 Pelotas (Brazil) Birth Cohort. The prevalence of maternal and perinatal outcomes in this population was also assessed. HDP were classified according to Ministry of Health recommendations. Medications were defined using the Anatomical Therapeutic Chemical Classification System and the substance name. In this cohort, 1336 (31.3%) of women had HDP. Gestational hypertension was present in 636 (47.6%) women, 409 (30.6%) had chronic hypertension, 191 (14.3%) pre-eclampsia, and 89 (6.7%) pre-eclampsia superimposed on chronic hypertension. Approximately 70% of women with HDP reported not using any cardiovascular medications. Methyldopa in monotherapy was the most frequent treatment (16%), regardless of the type of HDP. Omega-3 was the medication most frequently reported by women without HDP. Preterm delivery, caesarean section, low birth weight, and neonatal intensive care admissions were more prevalent in women with HDP. Patterns of use of methyldopa were in-line with the Brazilian guidelines as the first-line therapy for HDP. However, the large number of women with HDP not using medications to manage HDP requires further investigation.