Treatment of women with an abnormal glucose challenge test (but a normal oral glucose tolerance test) decreases the prevalence of macrosomia. Management of women with one abnormal oral glucose tolerance test value reduces adverse outcome in pregnancy. Effect of a low glycaemic index diet on blood glucose in women with gestational hyperglycaemia. Evaluating the therapeutic approach in pregnancies complicated by borderline glucose intolerance: a randomized clinical trial.
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. In this study we sought to test the hypothesis that treatment of women with one abnormal oral glucose tolerance test value will result in reduction of adverse outcome. One hundred twenty-six women with one abnormal oral glucose tolerance test value and 146 women in the control group (normal oral glucose tolerance test values) participated in a prospective study during the third trimester of pregnancy. The subjects with one abnormal test result were randomized into treated (group 1) and untreated groups (group II). Group 1 subjects were treated with a strict diabetic protocol to maintain tight glycemic control by means of diet and insulin therapy. Group 2 subjects tested their capillary blood glucose for a baseline period. The study revealed that the level of glycemic control was similar before initiation of therapy (mean capillary blood glucose 118 +/- 14 vs. 119 +/- 15 mg/dl, p = NS) for groups 1 and 2, respectively. There was a significant difference in mean capillary blood glucose (95 +/- 10 vs. 119 +/- 15 mg/dl, p less than 0.0001), preprandial, and postprandial determinations between the treated and untreated groups. The overall incidence of neonatal metabolic complications (4% vs. 14%, p less than 0.05) and large infants (6% vs. 24%, p less than 0.03) was significantly lower in the treated group. Comparison between the control (normal oral glucose tolerance test) and the untreated groups showed a significantly higher incidence of large infants and metabolic complications. No difference was found between the normal and treated groups. Thus we conclude that treatment of individuals with one abnormal oral glucose tolerance test value will result in significant reduction in adverse outcome in pregnancy. The objectives of this pilot study were to determine the feasibility and effect on glycaemic control of a low-glycaemic-index (GI) diet in women with gestational diabetes or impaired glucose tolerance of pregnancy.
                participants, recruited from the Diabetes-in-Pregnancy Clinic of an inner-city teaching hospital serving a predominantly non-Caucasian population, were randomized to a low-GI (n=23) or control (n=24) diet and followed from 28 weeks gestation until delivery. Self-monitored-blood-glucose (SMBG), maternal and infant weight were collected from medical charts. Dietary intakes were assessed using diet records and questionnaires.
                diet GI on control (58, 95% CI: 56,60) was significantly higher than on low-GI (49, 95% CI: 47,51; p=0.001). Glycaemic control improved on both diets, but more postprandial glucose values were within target on low-GI (58.4% of n=1891) than control (48.7% of n=1834; p<0.001). SMBG post-breakfast was directly related to pre-pregnancy BMI in the control, but not the low-GI group (BMI*diet interaction; p=0.021). Participants accepted the study foods and were willing to consume them post-intervention.
                a low-GI diet was feasible and acceptable in this sample and facilitated control of postprandial glucose. A larger study is needed to determine the effect of a low-GI diet on maternal and infant outcomes.
                2010. Published by Elsevier Ireland Ltd. 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.
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.