Evidence map›Paper›PMID 30894356›Full record

ArticleBMJ (Clinical research ed.)2019

Role of maternal age and pregnancy history in risk of miscarriage: prospective register based study.

Maria C Magnus, Allen J Wilcox, Nils-Halvdan Morken, Clarice R Weinberg, Siri E Håberg

Open access · hybridAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in BMJ (Clinical research ed.), 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 308 papers, 12 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
308citing papers in PubMed, 12 pooled it
61.9field-weighted citation impact, top 1% of its field
1 · What the graph read from it

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

308 citing papers in PubMed, 12 syntheses or guidelines pooled it, 681 citations in OpenAlex.

  1. Pooled it
  2. Clinical practice guideline "preconception care".Archives of gynecology and obstetrics · 2026
    Guideline
  3. Pooled it
  4. Pooled it
  5. Pooled it
  6. Pooled it
  7. Pooled it
  8. Pooled it
  9. Pooled it
  10. Pooled it
  11. Pooled it
  12. Pooled it
  13. Trial
  14. Trial
  15. Trial
  16. Trial
  17. Trial
  18. Trial
  19. Article
  20. Article

248 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 2 institutions in 3 countries.

Maria C MagnusCentre for Fertility and Health, Norwegian Institute of Public Health, PO Box 222 Skøyen, N-0213 Oslo, Norway.ORCID 0000-0002-0568-3774
Allen J WilcoxCentre for Fertility and Health, Norwegian Institute of Public Health, PO Box 222 Skøyen, N-0213 Oslo, Norway.
Nils-Halvdan MorkenCentre for Fertility and Health, Norwegian Institute of Public Health, PO Box 222 Skøyen, N-0213 Oslo, Norway.
Clarice R WeinbergBiostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, Durham, NC, USA.
Siri E HåbergCentre for Fertility and Health, Norwegian Institute of Public Health, PO Box 222 Skøyen, N-0213 Oslo, Norway.
Norwegian Institute of Public Health · NONational Institute of Environmental Health Sciences · US

Funding

Statistical Methods In Epidemiology--generalZIAES040006 · NIEHS · NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES · PI WEINBERG, CLARICE · 2009 to 2025
$4.5M
Medical Research Council MC_UU_00011/6Medical Research Council MR/M009351/1
6 · The paper itself

Abstract

objectivesTo estimate the burden of miscarriage in the Norwegian population and to evaluate the associations with maternal age and pregnancy history.

designProspective register based study.

settingMedical Birth Register of Norway, the Norwegian Patient Register, and the induced abortion register.

participantsAll Norwegian women that were pregnant between 2009-13.

main outcome measureRisk of miscarriage according to the woman's age and pregnancy history estimated by logistic regression.

resultsThere were 421 201 pregnancies during the study period. The risk of miscarriage was lowest in women aged 25-29 (10%), and rose rapidly after age 30, reaching 53% in women aged 45 and over. There was a strong recurrence risk of miscarriage, with age adjusted odds ratios of 1.54 (95% confidence interval 1.48 to 1.60) after one miscarriage, 2.21 (2.03 to 2.41) after two, and 3.97 (3.29 to 4.78) after three consecutive miscarriages. The risk of miscarriage was modestly increased if the previous birth ended in a preterm delivery (adjusted odds ratio 1.22, 95% confidence interval 1.12 to 1.29), stillbirth (1.30, 1.11 to 1.53), caesarean section (1.16, 1.12 to 1.21), or if the woman had gestational diabetes in the previous pregnancy (1.19, 1.05 to 1.36). The risk of miscarriage was slightly higher in women who themselves had been small for gestational age (1.08, 1.04 to 1.13).

conclusionsThe risk of miscarriage varies greatly with maternal age, shows a strong pattern of recurrence, and is also increased after some adverse pregnancy outcomes. Miscarriage and other pregnancy complications might share underlying causes, which could be biological conditions or unmeasured common risk factors.

Indexed as

Maternal AgeAbortion, HabitualAbortion, SpontaneousAdultAge FactorsFemaleHumansMiddle AgedNorwayPregnancyPregnancy OutcomePremature BirthProspective StudiesRecurrenceRegistriesReproductive History

Identifiers

PMID30894356
PMCPMC6425455
OpenAlexW2923117777

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.