ArticlePaediatric and perinatal epidemiology2026
Medication Exposure Definitions in Perinatal Pharmacoepidemiology: Implications for Pregnancy Studies.
Article in Paediatric and perinatal epidemiology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
3 citing papers in PubMed.
- Metformin Use Before Assisted Reproductive Technology and Pregnancy Outcomes in Women With Polycystic Ovary Syndrome: A Nationwide Cohort Study.Clinical pharmacology and therapeutics · 2026Article
- Exposure Definitions in Perinatal Pharmacoepidemiology: One Size Does Not Fit All.Paediatric and perinatal epidemiology · 2026Article
- Medication Exposure Definitions in Perinatal Pharmacoepidemiology: Implications for Pregnancy Studies.Paediatric and perinatal epidemiology · 2026Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundExposure definitions in real-world pregnancy studies vary across studies, data sources, treatments and outcomes, yet their impact on prevalence estimates remains unexamined.
objectivesTo identify the most used exposure definitions during the 1st trimester and evaluate their impact on prevalence estimates:
methodsWe reviewed 400 randomly selected articles on medication use during pregnancy to identify exposure definitions. Using Danish health registers (1997-2024) and the Québec Pregnancy Cohort (1998-2015), we analysed chronic, as-needed, and acute medication use. Prevalence (per 1000) was calculated per definition, including: (1) ≥ 1 or (2) ≥ 2 filled prescriptions during 1st trimester; filled ≥ 1 prescription anytime between the 1st trimester or (3) 30 days, (4) 60 days, (5) 90 days, (6) 6 months before conception; filled a prescription during 1st trimester or before conception, (7) assuming 1 daily defined dose per day or (8) prescribed days overlapping 1st trimester. Trends across cohorts and medications were compared.
resultsWe analysed 1,524,075 pregnancies in Denmark and 229,000 in Québec, Canada. The most common exposure definitions identified from the literature were Definition 1 (83%), followed by Definition 3 (13%). Prevalence varied across definitions, with differential impacts depending on medication and type of use. Definition 6 (1st trimester or within the 6 months before conception) yielded the highest prevalence; Definition 2 (≥ 2 fills in 1st trimester) the lowest. Broader time-windows of exposure increased prevalence, with variation by medication. The prevalence of medication use, whether chronic or acute, showed less variation across definitions than that of as-needed medication.
conclusionsMedication exposure prevalence varied by definition and medication. Using ≥ 1 filled prescriptions in the 1st trimester yielded prevalence estimates comparable to those from more complex definitions, supporting its use as a pragmatic standard. Sensitivity analyses and transparent reporting of exposure definition are essential to ensure replicability and critical appraisal.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.