Primary prevention of gestational diabetes mellitus and large-for-gestational-age newborns by lifestyle counseling: a cluster-randomized controlled trial. Treatment of women with an abnormal glucose challenge test (but a normal oral glucose tolerance test) decreases the prevalence of macrosomia. A randomized controlled trial investigating the effects of a low-glycemic index diet on pregnancy outcomes in gestational diabetes mellitus. Feasibility of a lifestyle intervention in early pregnancy to prevent deterioration of glucose tolerance. Evaluating the therapeutic approach in pregnancies complicated by borderline glucose intolerance: a randomized clinical trial. Universal vs. risk factor-based screening for gestational diabetes mellitus: detection rates, gestation at diagnosis and outcome. Advice that includes food sources of unsaturated fat supports future risk management of gestational diabetes mellitus. Randomized trial of diet versus diet plus cardiovascular conditioning on glucose levels in gestational diabetes. Effect of a low-glycemic-index diet during pregnancy on obstetric outcomes.
Our objective was to examine whether gestational diabetes mellitus (GDM) or newborns' high birthweight can be prevented by lifestyle counseling in pregnant women at high risk of GDM.
                We conducted a cluster-randomized trial, the NELLI study, in 14 municipalities in Finland, where 2,271 women were screened by oral glucose tolerance test (OGTT) at 8-12 wk gestation. Euglycemic (n = 399) women with at least one GDM risk factor (body mass index [BMI] ≥ 25 kg/m(2), glucose intolerance or newborn's macrosomia (≥ 4,500 g) in any earlier pregnancy, family history of diabetes, age ≥ 40 y) were included. The intervention included individual intensified counseling on physical activity and diet and weight gain at five antenatal visits. Primary outcomes were incidence of GDM as assessed by OGTT (maternal outcome) and newborns' birthweight adjusted for gestational age (neonatal outcome). Secondary outcomes were maternal weight gain and the need for insulin treatment during pregnancy. Adherence to the intervention was evaluated on the basis of changes in physical activity (weekly metabolic equivalent task (MET) minutes) and diet (intake of total fat, saturated and polyunsaturated fatty acids, saccharose, and fiber). Multilevel analyses took into account cluster, maternity clinic, and nurse level influences in addition to age, education, parity, and prepregnancy BMI. 15.8% (34/216) of women in the intervention group and 12.4% (22/179) in the usual care group developed GDM (absolute effect size 1.36, 95% confidence interval [CI] 0.71-2.62, p = 0.36). Neonatal birthweight was lower in the intervention than in the usual care group (absolute effect size -133 g, 95% CI -231 to -35, p = 0.008) as was proportion of large-for-gestational-age (LGA) newborns (26/216, 12.1% versus 34/179, 19.7%, p = 0.042). Women in the intervention group increased their intake of dietary fiber (adjusted coefficient 1.83, 95% CI 0.30-3.25, p = 0.023) and polyunsaturated fatty acids (adjusted coefficient 0.37, 95% CI 0.16-0.57, p < 0.001), decreased their intake of saturated fatty acids (adjusted coefficient -0.63, 95% CI -1.12 to -0.15, p = 0.01) and intake of saccharose (adjusted coefficient -0.83, 95% CI -1.55 to -0.11, p  =  0.023), and had a tendency to a smaller decrease in MET minutes/week for at least moderate intensity activity (adjusted coefficient 91, 95% CI -37 to 219, p = 0.17) than women in the usual care group. In subgroup analysis, adherent women in the intervention group (n = 55/229) had decreased risk of GDM (27.3% versus 33.0%, p = 0.43) and LGA newborns (7.3% versus 19.5%, p = 0.03) compared to women in the usual care group.
                The intervention was effective in controlling birthweight of the newborns, but failed to have an effect on maternal GDM.
                Current Controlled Trials ISRCTN33885819. Please see later in the article for the Editors' Summary. Infant macrosomia is a serious medical concern. Pregnant women who do not meet the specific diagnosis for gestational diabetes may still have glucose-mediated macrosomia. In Santa Barbara County all pregnant women are screened for gestational diabetes at 24-28 weeks with a 50-g, 1-hr glucose challenge test (GCT). All patients who fail this test are placed on a standard euglycemic diet (40% carbohydrate, 20% protein, 40% fat) and perform home glucose monitoring of fasting and postprandial glucose levels. The objective of this study was to examine the effectiveness of this treatment program in decreasing infant macrosomia, maternal and infant morbidity, maternal complications, and operative delivery. We studied 103 women who had a positive GCT, but a negative 100-g, 3-hr oral glucose tolerance test (OGTT). The women were randomly assigned to either experimental or control groups with experimental women receiving dietary counseling and home glucose monitoring instruction (HBGM). HBGM diaries were reviewed weekly by clinic nurses. All women had hemoglobin A1c (HbA1c) tests at 28 and 32 weeks. Maternal and fetal charts were reviewed to determine delivery type and complications, indications for cesarean section (C-section), and infant gestational age, gender, Apgar scores, birth weight, morbidities, and congenital anomalies. Of the 103 women, 5 women required insulin treatment, 1 woman had an abortion, and 14 women were indeterminate regarding compliance or were control women who received diet counseling and HBGM. The results are based on 83 women--48 control and 35 experimental. There were no significant differences between the groups for age, parity, or weight at 28-30 weeks or 37 weeks to delivery, or HbA1c at 28 weeks. HbA1c was significantly higher in control women at 32 weeks. Birth weight expressed in grams or as a percentile specific for gender, ethnicity, and gestational age was significantly higher in control infants. Birth weight was significantly correlated with maternal intake weight, weight at 28-30 weeks, and weight at delivery and with HbA1c at 32 weeks' gestation. There were no significant differences between groups for maternal complications. Groups were significantly different for mode of delivery with experimental women having more induced vaginal deliveries but fewer repeat C-sections than control women. Groups were not different for primary C-sections. Women who fail the GCT, but not the OGTT and thus do not receive the diagnosis of GDM are still at risk for delivering a macrosomic infant and operative delivery. Our program of treatment for all women who fail the GCT improves outcome by reducing infant birth weight and the number of cesarean sections. The prevalence of gestational diabetes mellitus (GDM) is rising. There is little evidence to demonstrate the effectiveness of one dietary therapy over another. We aimed to investigate the effect of a low-glycemic index (LGI) versus a conventional high-fiber diet on pregnancy outcomes, neonatal anthropometry, and maternal metabolic profile in GDM.
                Ninety-nine women (age 26-42 years; mean ± SD prepregnancy BMI 24 ± 5 kg/m²) diagnosed with GDM at 20-32 weeks' gestation were randomized to follow either an LGI (n = 50; target glycemic index [GI] ~50) or a high-fiber moderate-GI diet (HF) (n = 49; target GI ~60). Dietary intake was assessed by 3-day food records. Pregnancy outcomes were collected from medical records.
                The LGI group achieved a modestly lower GI than the HF group (mean ± SEM 47 ± 1 vs. 53 ± 1; P < 0.001). At birth, there was no significant difference in birth weight (LGI 3.3 ± 0.1 kg vs. HF 3.3 ± 0.1 kg; P = 0.619), birth weight centile (LGI 52.5 ± 4.3 vs. HF 52.2 ± 4.0; P = 0.969), prevalence of macrosomia (LGI 2.1% vs. HF 6.7%; P = 0.157), insulin treatment (LGI 53% vs. HF 65%; P = 0.251), or adverse pregnancy outcomes.
                In intensively monitored women with GDM, an LGI diet and a conventional HF diet produce similar pregnancy outcomes. In conjunction with the growing prevalence of obesity and the older age of pregnant women gestational diabetes (GDM) is a major health problem.The aim of the study was to evaluate if a lifestyle intervention since early pregnancy is feasible in improving the glucose tolerance of women at a high-risk for GDM in Finland.
                A 75-g oral glucose tolerance test (OGTT) was performed in early pregnancy (n = 102). Women at high risk for GDM (n = 54) were randomized at weeks 8-12 from Apr 2005 to May 2006 to a lifestyle intervention group (n = 27) or to a close follow-up group (n = 27). An OGTT was performed again at weeks 26-28 for the lifestyle intervention and close follow-up groups.
                The values of the OGTT during the second trimester did not differ between the lifestyle intervention and close follow-up groups. In the lifestyle intervention group three women had GDM in the second trimester and respectively one woman in the close follow up group. Insulin therapy was not required in both groups. The intervention resulted in somewhat lower weight gain 11.4 ± 6.0 kg vs. 13.9 ± 5.1 kg, p = 0.062, adjusted by the prepregnancy weight.
                Early intervention with an OGTT and simple lifestyle advice is feasible. A more intensive lifestyle intervention did not offer additional benefits with respect to glucose tolerance, although it tended to ameliorate the weight gain.
                ClinicalTrials.gov: NCT01130012. Most studies relating minor gestational metabolic alterations to macrosomia refer to glucose intolerance classified on the basis of the National Diabetes Data Group or previous World Health Organization diagnostic thresholds. Our aim was to evaluate the consequences of very mild forms of gestational glucose intolerance, defined by an elevated 50-g glucose challenge test followed by a normal oral glucose tolerance test, using the more restrictive Carpenter and Coustan's criteria (Borderline Gestational Glucose Intolerance, BGGI).
                Three hundred BGGI women were randomly assigned to: Group A (standard management), Group B (dietary treatment and regular monitoring). A control group (C) was also considered. Newborns were classified as macrosomic, large (LGA), or small for gestational age (SGA).
                The three groups were similar in age, body mass index and parity. Therapy in Group B significantly improved fasting (from 4.68 +/- 0.45 to 4.28 +/- 0.45 mmol/l) and 2-h postprandial glycaemia (from 6.01 +/- 0.57 to 5.13 +/- 0.68 mmol/l). Fasting glycaemia at delivery was significantly lower in B (4.20 +/- 0.38 mmol/l) than in A (4.84 +/- 0.45 mmol/l), and was also lower than in C (4.31 +/- 0.39 mmol/l). Significantly fewer LGA babies were born to Group B (6.0%) than Group A (14.0%) and Group C (9.1%). No difference was found in the SGA rate. The neonatal Ponderal Index was higher (P = 0.030) in group A (2.73 +/- 0.35) than in C (2.64 +/- 0.30) and B (2.64 +/- 0.24).
                Even very mild alterations in glucose tolerance can result in excessive or disharmonious fetal growth, which may be prevented by simple, non-invasive therapeutic measures. Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcome. Screening for GDM is therefore recommended but the best screening method remains controversial. This prospective, randomized study compared a risk factor-based screening programme with a universally based one.
                Subjects were randomized at booking to one of two groups: the risk factor group had a 3-h 100-g oral glucose tolerance test (OGTT) at 32 weeks if any risk factor for GDM was present; the universal group had a 50-g glucose challenge test performed and if their plasma glucose at 1 h was > or = 7.8 mmol/l, a formal 3-h 100-g OGTT was then performed.
                Universal screening detected a prevalence of GDM of 2.7%, significantly more than the 1.45% detected in the risk factor screened group (P<0.03). Universal screening facilitated earlier diagnosis than risk factor screening - mean gestation 30 +/- 2.6 weeks vs. 33 +/- 3.7 weeks (P<0.05). A higher rate of spontaneous vaginal delivery at term, and lower rates of macrosomia, Caesarean section, prematurity, pre-eclampsia and admission to neonatal intensive care unit were observed in the universally screened, early diagnosis group.
                Universal screening for GDM is superior to risk factor based screening-detecting more cases, facilitating early diagnosis and is associated with improved pregnancy outcome. Abstract Women with gestational diabetes mellitus (GDM) have a greater risk of developing type 2 diabetes mellitus (DM) and heart disease than pregnant women without GDM. Advice given during the GDM pregnancy provides an opportunity to develop protective dietary patterns for the long-term management of this risk. Dietary guidelines for the prevention and management of type 2 DM support the inclusion of unsaturated fats, but food advice needs to target this outcome. The aim of this study was to compare the dietary intakes of women with GDM given general low-fat advice (control group) to women with GDM given the same advice with additional targets for food sources of unsaturated fats (intervention group). After approximately 6 weeks, the intervention group reported more ideal dietary fatty acid intakes than the control group, with polyunsaturated:saturated fat ratios of 1:1 and 0.4:1, respectively ( P < .001), assessed using repeated measures analysis of variance. These results confirm the need to include food sources of unsaturated fats in advice strategies to assure optimal protective eating habits in this at-risk group. We studied the impact of a training program on glucose tolerance in gestational diabetes mellitus. Women with gestational diabetes mellitus (N = 19) were randomized into either group I, a 6-week diet alone group (24 to 30 kcal/kg/24 hours; 20% protein, 40% carbohydrate, 40% fat), or group II, which followed the same diet plus exercise (20 minutes three times a week for 6 weeks). An arm ergometer was used to maintain heart rate in the training range. Glycemic response was monitored by glycosylated hemoglobin, a 50 gm oral glucose challenge with a fasting and 1-hour plasma glucose, and blood glucose self-monitoring, fasting and 1 hour after meals. Week 1 glycemic parameters were the same for both groups. Week 6 data (mean +/- SD) were as follows: group I glycosylated hemoglobin, 4.7% + 0.2% versus group II, 4.2% +/- 0.2%; p less than 0.001. The group I glucose challenge fasting value was 87.6 +/- 6.2 versus 70.1 +/- 6.6 mg/dl, p less than 0.001 for group II. The group I 1-hour plasma glucose challenge result was 187.5 +/- 12.9 mg/dl versus 105.9 +/- 18.9 mg/dl for group II, p less than 0.001. The glycemic levels diverged between the groups at week 4. We conclude that arm ergometer training is feasible in women with gestational diabetes mellitus and results in lower glycosylated hemoglobin, fasting, and 1-hour plasma glucose concentrations than diet alone. Arm ergometer training may provide a useful treatment option for women with gestational diabetes mellitus and may obviate insulin treatment. Pregnancy is a condition in which the glycemic index (GI) may be of particular relevance because maternal glucose is the main energy substrate for intrauterine growth.
                The aim was to compare the effects of low-GI and conventional dietary strategies on pregnancy outcomes in healthy women. Compliance and acceptability were also investigated.
                The subjects were assigned alternately to receive dietary counseling that encouraged either low-GI (LGI) carbohydrate foods or high-fiber, moderate-to-high GI (HGI) foods and were studied 5 times between <16 wk gestation and delivery. Of the 70 women who met the inclusion criteria, 62 completed the study (32 in the LGI and 30 in the HGI groups). Primary outcomes were measures of fetal size.
                The mean diet GI fell significantly in the LGI group but not in the HGI group. Compared with the LGI group, women in the HGI group gave birth to infants who were heavier (3408 +/- 78 compared with 3644 +/- 90 g; P = 0.051) and had a higher birth centile (48 +/- 5 compared with 69 +/- 5; P = 0.005), a higher ponderal index (2.62 +/- 0.04 compared with 2.74 +/- 0.04; P = 0.03), and a higher prevalence of large-for-gestational age (3.1% compared with 33.3%; P = 0.01). Women in the LGI group found the diet easier to follow.
                Because birth weight and ponderal index may predict chronic disease in later life, a low-GI diet may favorably influence long-term outcomes.
This review found interventions including providing dietary advice and blood glucose level monitoring for women with pregnancy hyperglycaemia not meeting GDM and T2DM diagnostic criteria helped reduce the number of macrosomic and LGA babies without increasing caesarean section and operative vaginal birth rates. It is important to notice that the results of this review were based on four small randomised trials with moderate to high risk of bias without follow-up outcomes for both women and their babies.