Nav: Home

Higher iron levels are associated with an increased risk of gestational diabetes in pregnant women, raising questions about iron supplementation recommendations

November 10, 2016

New research published in Diabetologia (the journal of the European Association for the Study of Diabetes [EASD]) shows that high levels of iron biomarkers in the body are associated with an increased risk of gestational diabetes (GDM) in pregnant women, raising questions about routine recommendations on iron supplementation in pregnancy. The study is by Dr Cuilin Zhang and Dr Shristi Rawal, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), US National Institutes of Health (NIH), Bethesda, MD, USA and colleagues.

Iron is regarded as a double-edged sword in living systems, as both iron deficiency andexcess can be harmful. Pregnant women are particularly vulnerable to iron deficiency and related adverse pregnancy outcomes. While a few guidelines, including those from the American Congress of Obstetricians and Gynecologists, recommend screening and treatment only as necessary for iron deficiency, several other groups such as the World Health Organization (WHO) and the Centers for Disease Control and Prevention recommend routine iron supplementation among pregnant women. Emerging evidence has pointed to a possible link between higher iron stores and abnormal blood sugar control (including type 2 diabetes) in non-pregnant individuals.

In this new research, the authors did a case-control study of 107 GDM cases and 214 controls (matched on age, race/ethnicity, and gestational week of blood collection) within the prospective, multiracial NICHD Fetal Growth Studies-Singleton Cohort (2009-2013). The authors looked at several biomarkers of iron status, including plasma hepcidin, ferritin, and soluble transferrin receptor (sTfR), and these data were used to calculate the sTfR:ferritin ratio, which captures both cellular iron need and availability of body iron stores. These markers were longitudinally measured or calculated four times during pregnancy, twice before GDM diagnosis (gestational weeks 10-14 and 15-26), and twice afterwards (gestational weeks 23-31 and 33-39). GDM diagnosis was ascertained from medical records based on oral glucose tolerance test results. Statistical modelling was then used to calculate the odds ratio of GDM with iron status, accounting for factors such as demographics, pre-pregnancy body mass index (BMI), and other major risk factors.

The authors found that for both hepcidin and ferritin, in the second trimester of pregnancy, those in the top 25% of levels of these markers had around a 2.5 times increased subsequent risk of developing GDM compared with those in the bottom 25%. Similar findings were observed for ferritin levels in the first trimester.

Describing the findings as biologically plausible, the authors offer various potential explanations. Iron may play a role in the development of GDM through several potential mechanisms. As a strong pro-oxidant, free iron can promote several cellular reactions that generate reactive oxygen species and increase the level of oxidative stress. Oxidative stress induced from excess iron accumulation can cause damage to and death of pancreatic beta cells which produce insulin, and consequently, contribute to impaired insulin synthesis and secretion. In the liver, high iron stores may induce insulin resistance via impaired insulin signalling as well as by limiting the capacity of the liver to extract insulin.

The authors conclude: "In summary, findings from this longitudinal and prospective study among multiracial, relatively healthy pregnant women without major pre-pregnancy chronic diseases, suggest that higher maternal iron stores may play a role in the development of GDM starting as early as the first trimester. These findings are of clinical and public health importance as they extend the observation of an association between high body iron stores and elevated risk of glucose intolerance among non-pregnant individuals to pregnancy, and raise potential concerns about the recommendation of routine iron supplementation among pregnant women who already have sufficient iron."
-end-


Diabetologia

Related Diabetes Articles:

Tele-diabetes to manage new-onset diabetes during COVID-19 pandemic
Two new case studies highlight the use of tele-diabetes to manage new-onset type 1 diabetes in an adult and an infant during the COVID-19 pandemic.
Genetic profile may predict type 2 diabetes risk among women with gestational diabetes
Women who go on to develop type 2 diabetes after having gestational, or pregnancy-related, diabetes are more likely to have particular genetic profiles, suggests an analysis by researchers at the National Institutes of Health and other institutions.
Maternal gestational diabetes linked to diabetes in children
Children and youth of mothers who had gestational diabetes during pregnancy are at increased risk of diabetes themselves, according to new research published in CMAJ (Canadian Medical Association Journal).
Two diabetes medications don't slow progression of type 2 diabetes in youth
In youth with impaired glucose tolerance or recent-onset type 2 diabetes, neither initial treatment with long-acting insulin followed by the drug metformin, nor metformin alone preserved the body's ability to make insulin, according to results published online June 25 in Diabetes Care.
People with diabetes visit the dentist less frequently despite link between diabetes, oral health
Adults with diabetes are less likely to visit the dentist than people with prediabetes or without diabetes, finds a new study led by researchers at NYU Rory Meyers College of Nursing and East Carolina University's Brody School of Medicine.
Diabetes, but not diabetes drug, linked to poor pregnancy outcomes
New research indicates that pregnant women with pre-gestational diabetes who take metformin are at a higher risk for adverse pregnancy outcomes -- such as major birth defects and pregnancy loss -- than the general population, but their increased risk is not due to metformin but diabetes.
New oral diabetes drug shows promise in phase 3 trial for patients with type 1 diabetes
A University of Colorado Anschutz Medical Campus study finds sotagliflozin helps control glucose and reduces the need for insulin in patients with type 1 diabetes.
Can continuous glucose monitoring improve diabetes control in patients with type 1 diabetes who inject insulin
Two studies in the Jan. 24/31 issue of JAMA find that use of a sensor implanted under the skin that continuously monitors glucose levels resulted in improved levels in patients with type 1 diabetes who inject insulin multiple times a day, compared to conventional treatment.
Complications of type 2 diabetes affect quality of life, care can lead to diabetes burnout
T2D Lifestyle, a national survey by Health Union of more than 400 individuals experiencing type 2 diabetes (T2D), reveals that patients not only struggle with commonly understood complications, but also numerous lesser known ones that people do not associate with diabetes.
A better way to predict diabetes
An international team of researchers has discovered a simple, accurate new way to predict which women with gestational diabetes will develop type 2 diabetes after delivery.
More Diabetes News and Diabetes Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.