***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE Higher heme iron intake is associated with increased  type 2 diabetes risk .  However , no previous study has evaluated gestational diabetes mellitus ( GDM ) risk in relation to heme iron intake during pregnancy . We investigated associations of maternal preconceptional and early pregnancy heme and nonheme iron intake with subsequent GDM risk . RESEARCH DESIGN AND METHODS We conducted a prospect i ve cohort study of 3,158 pregnant women . A food frequency question naire was used to assess maternal diet . Multivariable generalized linear regression models were used to derive estimates of relative risks ( RRs ) and 95 % CIs . RESULTS Approximately 5.0 % of the cohort developed GDM ( n = 158 ) . Heme iron intake was positively and significantly associated with GDM risk ( Ptrend = 0.04 ) . After adjusting for confounders , women reporting the highest heme iron intake levels ( ≥1.52 vs. < 0.48 mg per day ) experienced a 3.31-fold – increased GDM risk ( 95 % CI 1.02–10.72 ) . In fully adjusted models , we noted that a 1-mg per day increase in heme iron was associated with a 51 % increased GDM risk ( RR 1.51 [ 95 % CI 0.99–2.36 ] ) . Nonheme iron was inversely , though not statistically significantly , associated with GDM risk , and the corresponding RRs were 1.00 , 0.83 , 0.62 , and 0.61 across quartiles of nonheme iron intake ( Ptrend = 0.08 ) . CONCLUSIONS High levels of dietary heme iron intake during the preconceptional and early pregnancy period may be associated with increased GDM risk . Associations of GDM risk  with dietary nonheme iron intake are less clear . Confirmation of these findings by future studies is warranted OBJECTIVE It is important to identify modifiable factors that may lower gestational diabetes mellitus ( GDM ) risk .  Dietary iron is of particular interest given that iron is a strong prooxidant , and high body iron levels can damage pancreatic β-cell function and impair glucose metabolism . The current study is to determine if prepregnancy dietary and supplemental iron intakes are associated with the risk of GDM . RESEARCH DESIGN AND METHODS A prospect i ve study was conducted among 13,475 women who reported a singleton pregnancy between 1991 and 2001 in the Nurses ’ Health Study II . A total of 867 incident GDM cases were reported . Pooled logistic regression was used to estimate the relative risk ( RR ) of GDM by quintiles of iron intake controlling for dietary and nondietary risk factors . RESULTS  Dietary heme iron intake was positively and significantly associated with GDM risk . After adjusting for age , BMI , and other risk factors , RRs ( 95 % CIs ) across increasing quintiles of heme iron were 1.0 ( reference ) , 1.11 ( 0.87–1.43 ) , 1.31 ( 1.03–1.68 ) , 1.51 ( 1.17–1.93 ) , and 1.58 ( 1.21–2.08 ) , respectively ( P for linear trend 0.0001 ) . The multivariate adjusted RR for GDM associated with every 0.5-mg per day of increase in intake was 1.22 ( 1.10–1.36 ) . No significant associations were observed between total dietary , nonheme , or supplemental iron intake and GDM risk . CONCLUSIONS These findings suggest that higher prepregnancy intake of dietary heme iron is associated with an increased GDM risk AIM To examine the prediction of gestational diabetes in obese women using routine clinical measures and measurement of biomarkers related to insulin resistance in the early second trimester . METHODS A total of 117 obese pregnant women participating in a pilot trial of a complex intervention of dietary advice and physical activity  were studied . Blood sample s were obtained at recruitment ( 15⁺⁰-17⁺⁶ weeks ' gestation ) and demographic , clinical history and anthropometric measures recorded . The biomarkers analysed were plasma lipids ( HDL cholesterol , LDL cholesterol , triglycerides ) , high-sensitivity C-reactive protein , alanine transaminase , aspartate transaminase , ferritin , fructosamine , insulin , adiponectin , tissue plasminogen activator , interleukin-6 , visfatin and leptin . Univariate and logistic regression analyses were performed to determine independent predictors and area under the receiver-operating curve was calculated for the model . RESULTS Of the 106 participants included in the analysis , 29 ( 27.4 % ) developed gestational diabetes . Participants with gestational diabetes were older ( P = 0.002 ) , more often of parity ≥ 2 , had higher systolic ( P = 0.02 ) and diastolic blood pressure ( P = 0.02 ) and were more likely to be black ( P = 0.009 ) . Amongst the blood biomarkers measured , plasma adiponectin alone remained independently associated with gestational diabetes in adjusted models ( P = 0.002 ) . The area under the receiver-operating curve for clinical factors alone ( 0.760 ) increased significantly ( area under the curve 0.834 , chi-square statistic ( 1 ) = 4.00 , P = 0.046 ) with the addition of adiponectin . CONCLUSIONS A combination of routinely measured clinical factors and adiponectin measured in the early second trimester in obese women may provide a useful approach to the prediction of gestational diabetes . Validation in a large prospect i ve study is required to determine the usefulness of this algorithm in clinical practice Aims /hypothesisThe aim of this study was to prospect ively examine whether dietary patterns are related to risk of gestational diabetes mellitus ( GDM ) .  Methods This prospect i ve cohort study included 13,110 women who were free of cardiovascular disease , cancer , type 2 diabetes and history of GDM . Subjects completed a vali date d semi-quantitative food frequency question naire in 1991 , and reported at least one singleton pregnancy between 1992 and 1998 in the Nurses ’ Health Study II . Two major dietary patterns ( i.e. ‘ prudent ’ and ‘ Western ’ ) were identified through factor analysis . The prudent pattern was characterised by a high intake of fruit , green leafy vegetables , poultry and fish , whereas the Western pattern was characterised by high intake of red meat , processed meat , refined grain products , sweets , French fries and pizza . Results We documented 758 incident cases of GDM . After adjustment for age , parity , pre-pregnancy BMI and other covariates , the relative risk ( RR ) of GDM , comparing the highest with the lowest quintile of the Western pattern scores , was 1.63 ( 95 % CI 1.20–2.21 ; ptrend=0.001 ) , whereas the RR comparing the lowest with the highest quintile of the prudent pattern scores was 1.39 ( 95 % CI 1.08–1.80 ; ptrend=0.018 ) . The RR for each increment of one serving/day was 1.61 ( 95 % CI 1.25–2.07 ) for red meat and 1.64 ( 95 % CI 1.13–2.38 ) for processed meat . Conclusions /interpretationThese findings suggest that pre-pregnancy dietary patterns may affect women ’s risk of developing GDM . A diet high in red and processed meat was associated with a significantly elevated risk Objective To investigate the possible association between total daily iron intake during pregnancy , haemoglobin in early pregnancy and the risk of gestational diabetes mellitus ( GDM ) in women at increased risk of GDM . Design A prospect i ve cohort study ( based on a cluster-r and omised controlled trial , where the intervention and the usual care groups were combined ) . Setting Primary healthcare maternity clinics in 14 municipalities in south-western Finl and . Participants 399 Pregnant women who were at increased risk of GDM participated in a GDM prevention trial and were followed throughout pregnancy . Main outcome measurements The main outcome was GDM diagnosed with oral glucose tolerance test at 26–28 weeks ’ gestation or based on a diagnosis recorded in the Finnish Medical Birth registry . Data on  iron intake was collected using a 181-item food frequency question naire and separate questions for supplement use at 26–28 weeks ’ gestation . Results  GDM was diagnosed in 72 women ( 18.1 % ) in the study population . The OR for total iron intake as a continuous variable was 1.006 ( 95 % CI 1.000 to 1.011 ; p=0.038 ) after adjustment for body mass index , age , diabetes in first-degree or second-degree relatives , GDM or macrosomia in earlier pregnancy , total energy intake , dietary fibre , saturated fatty acids and total gestational weight gain . Women in the highest fifth of total daily iron intake had an adjusted OR of 1.66 ( 95 % CI 0.84 to 3.30 ; p=0.15 ) for GDM . After excluding participants with low haemoglobin levels ( ≤120 g/l ) already in early pregnancy the adjusted OR was 2.35 ( 95 % CI 1.13 to 4.92 ; p=0.023 ) . Conclusions Our results suggest that high iron intake during pregnancy increases the risk of GDM especially in women who are not anaemic in early pregnancy and who are at increased risk of GDM . These findings suggest that routine iron supplementation should be reconsidered in this risk group of women OBJECTIVE — We examined the influence of a moderately elevated serum ferritin level at entry to care on the risk of gestational diabetes mellitus ( GDM ) and a possible mechanism ( increased iron stores versus inflammation ) . RESEARCH DESIGN AND METHODS — In a prospect i ve observational study with 1,456 healthy pregnant women in Camden , New Jersey , serum ferritin and anthropometric measurements were determined .  Serum C-reactive protein ( CRP ) concentration was measured in a nested case-control study of 172 subjects . RESULTS — Women who developed GDM had a higher concentration of serum ferritin than women who did not develop GDM ( P < 0.001 ) . Elevated serum ferritin level ( highest quintile ) was significantly and positively correlated with prepregnant BMI and skinfold measurements . Women in the highest quintile of serum ferritin had a twofold increased risk of developing GDM adjusted for several known risk factors ( adjusted odds ratio , 2.02 [ 95 % CI 1.04–3.92 ] , P < 0.05 ) . Similar results were obtained with a nested case-control study , in which women in the highest tertile of serum ferritin ( 2.35 [ 1.06–5.22 ] , P < 0.05 ) or CRP ( 2.67 [ 1.16–6.17 ] , P < 0.001 ) had a greater than twofold increased risk of GDM . However , these effects were modified and became nonstatistically significant after additional adjustment for prepregnant BMI . CONCLUSIONS — Elevated serum ferritin concentrations early in gestation are associated with an increased risk of GDM . The association , at least in part , is mediated by the maternal fat mass and obesity . These data suggest a possible link between elevated serum ferritin and low- grade inflammation OBJECTIVE To determine if the reported features of decreased iron store in the infant of diabetic mother are related to underlying maternal iron deficiency , a prospect i ve case-control study was performed on a group of low-risk antenatal patients without preexisting anemia or thalassemia trait and before the diagnosis of gestational diabetes mellitus ( GDM ) in the last trimester . RESEARCH DESIGN AND METHODS At the time of routine screening for anemia and GDM at 28–30 weeks of gestation , an additional blood sample was collected for the assay of serum ferritin , iron , and total iron binding capacity ( TIBC ) .  Patients with elevated r and om sugar underwent a 75-g oral glucose tolerance test ( OGTT ) , interpreted by the World Health Organization criteria . For each person diagnosed with GDM , a control subject matched in maternal age and parity was identified , and their iron status and hematological indexes were compared . RESULTS There were 60 patients with gestational impaired glucose tolerance ( GIGT ) , and none had frank GDM . There was no difference in the hematological indexes or serum iron and TIBC values , but serum ferritin level was significantly increased in the GIGT group , when compared with control subjects . CONCLUSIONS The findings indicate that there was no evidence of preexisting iron deficiency in the third trimester before the diagnosis of GIGT , while serum ferritin was even increased in the GIGT patients , a phenomenon that could have reflected the glucose intolerance . Serum ferritin is probably an unreliable index for maternal iron therapy in these patients , and the role of iron therapy in GIGT patients remains to be established AIM To determine whether non-anaemic women with gestational diabetes mellitus ( GDM ) diagnosed in third trimester pregnancy have evidence 
    Output:
    
Increased dietary intake of heme iron and body iron status are positively associated with the risk of GDM development in pregnant women .