Evidence map›Paper›PMID 40916351›Full record

Trial reportDiabetes/metabolism research and reviews2025

The Effect of Metformin on Insulin Requirement, Glycaemic Control and Weight Gain in Type 1 Diabetes During Pregnancy-a Randomised, Placebo-Controlled Multicentre Study.

Elina Juuma, Kati Tihtonen, Saara E Metso, Päivi M Hannula, Mika Helminen, Kristiina Tertti, Heidi Immonen, Leena Georgiadis, Kirsi Väyrynen, Petteri Ahtiainen and 4 more

Registry-linked trialAbstract readRandomized Controlled TrialMulticenter Study
PubMed Full text at PMC Publisher
In one paragraph

Trial report in Diabetes/metabolism research and reviews, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It reports registered trial NCT03765359. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
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.

NCT03765359 phase4completed

Metformin Use to Improve Pregnancy Outcome in Women With Type 1 Diabetes. A Randomized Double-blind Placebo-controlled Multicenter Study.

Ran2019Enrolled101Registered outcomes35Posted comparisons0ConditionsDiabetic Pregnancy, Insulin Resistance, Type1diabetesArmsmetforminhydrochloride, Placebo Oral Tablet
Open the trial in the graph
3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Trial
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

14 authors.

Elina JuumaFaculty of Medicine and Health Technology, Tampere University, Tampere, Finland.ORCID 0000-0001-6978-2600
Kati TihtonenFaculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
Saara E MetsoFaculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
Päivi M HannulaFaculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
Mika HelminenTays Research Services, Tampere University Hospital, Wellbeing Services County of Pirkanmaa, Tampere, Finland.
Kristiina TerttiFaculty of Medicine, University of Turku, Turku, Finland.
Heidi ImmonenFaculty of Medicine, University of Turku, Turku, Finland.
Leena GeorgiadisDepartment of Obstetrics and Gynecology, Helsinki University Hospital, Helsinki, Finland.
Kirsi VäyrynenDepartment of Obstetrics and Gynecology, Wellbeing Services County of Central Finland, Jyväskylä, Finland.
Petteri AhtiainenDepartment of Internal Medicine, Wellbeing Services County of Central Finland, Jyväskylä, Finland.
Hilkka NikkinenResearch Unit of Clinical Medicine, Medical Research Center, University of Oulu, Oulu, Finland.
Minna KoivikkoResearch Unit of Clinical Medicine, Medical Research Center, University of Oulu, Oulu, Finland.
Hannele LaivuoriDepartment of Obstetrics and Gynecology, Wellbeing Services County of Pirkanmaa, Tampere University Hospital, Tampere, Finland.
Jukka UotilaFaculty of Medicine and Health Technology, Tampere University, Tampere, Finland.

Funding

Diabetes Research FoundationFinnish Medical FoundationHilja and Onni Tuovinen FoundationInstrumentarium Science FoundationJalmari and Rauha Ahokas FoundationMaud Kuistila Memorial FoundationOrion Research FoundationState research funding, Wellbeing Services County of North SavoState research funding, Wellbeing Services County of PirkanmaaTampere University Hospital Support Foundation
6 · The paper itself

Abstract

aimOur aim was to ascertain whether metformin can reduce insulin requirement without compromising glycaemic control during pregnancy in women with type 1 diabetes.

methodsA total of 126 pregnant women with type 1 diabetes were recruited for a randomised, double-blind, placebo-controlled multicentre study. The primary outcome was total insulin change, defined as the difference between baseline and third trimester maximum insulin dose (IU).

resultsFifty women in the placebo group and 51 women in the metformin group completed the study. A predetermined sample size of 200 participants was not achieved. There was no significant difference in the primary outcome, that is, in the change of total insulin requirement (33 vs. 27 IU, p = 0.193). However, the metformin group showed a significantly lower increase in the prandial insulin change, with 24 versus 14 IU (p = 0.014) and 0.3 versus 0.2 IU/kg (p = 0.048). In the exploratory subgroup analysis, metformin attenuated prandial insulin increase in women with high BMI (> 25 kg/m

conclusionsMetformin was not shown to affect total insulin change but reduced the prandial insulin change and improved weight gain control especially in insulin-resistant subgroups. These findings warrant further studies on metformin as an adjunctive medicine.

trial registrationClinicalTrials.gov: NCT03765359.

Indexed as

Diabetes Mellitus, Type 1Glycemic ControlHypoglycemic AgentsInsulinMetforminPregnancy in DiabeticsWeight GainAdultBiomarkersBlood GlucoseDouble-Blind MethodFemaleFollow-Up StudiesGlycated HemoglobinHumansPregnancyBiomarkersBlood GlucoseGlycated Hemoglobinhemoglobin A1c protein, humanHypoglycemic AgentsInsulinMetformindiabetes type 1insulin resistancemetforminplacebopregnancy

Identifiers

PMID40916351
PMCPMC12415408

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
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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 Socratic graph.