Dietary therapy for gestational diabetes: how long is long enough?

OBJECTIVE: To determine the length of time required for dietary therapy alone to effect good glycemic control and whether the need for insulin treatment can be predicted at diagnosis of gestational diabetes mellitus (GDM). METHODS: Women with GDM were treated with dietary therapy for 4 weeks. Each measured her blood glucose using a memory-based reflectance glucometer, and those in poor glycemic control (mean glucose exceeding 105 mg/dL) after 4 weeks of dietary therapy were prescribed insulin. Women were stratified by fasting plasma glucose value of 3-hour glucose tolerance tests (GTTs). RESULTS: Women with fasting glucose at or below 95 mg/dL were significantly more likely to achieve good glycemic control after 2 weeks of dietary therapy than were those with values above 95 mg/dL whose control did not improve during the study. Receiver operating characteristic (ROC) analysis determined that fasting values of GTT between 91 and 95 mg/dL best predicted that insulin would be needed for good glycemic control. CONCLUSION: Women with GDM should be prescribed dietary therapy alone for at least 2 weeks before they are prescribed insulin. In those with fasting glucose above 95 mg/dL, insulin may be prescribed after 1 week of dietary therapy, or at diagnosis.

Anthropometric differences in macrosomic infants of diabetic and nondiabetic mothers.

The objective was to investigate the hypothesis that anthropometric and body composition differences exist between macrosomic infants of diabetic and nondiabetic mothers. Sixteen infants of mothers with diabetes, along with 58 control infants, were studied within 24 hours of delivery. The following measurements were obtained: birthweight, birth length and extremity length; circumferences of the head, chest, shoulders, and extremities; and triceps, subscapular, flank, and thigh skinfolds. Estimation of fat mass and calculation of percent body fat was performed according to the Dauncey method. Macrosomic infants of diabetic mothers were characterized by larger shoulder and extremity circumferences, a decreased head-to-shoulder ratio, significantly higher body fat, and thicker upper extremity skinfolds compared with nondiabetic control infants of similar birthweight and birth length. Differences in body composition and weight distribution may explain the propensity for shoulder dystocia in the diabetic population.

Perinatal outcome and the type and number of maneuvers in shoulder dystocia.

OBJECTIVES: To ascertain the type and order of maneuvers that should be used for the treatment of shoulder dystocia, and to determine its correlation with perinatal outcome. METHODS: We reviewed all consecutive cases of shoulder dystocia from January 1986 to August 1994 in our institution to obtain the type, order and number of maneuvers used for delivery. Patients were stratified by the number of maneuvers required for delivery. Outcome parameters included cord pH, Apgar score, neonatal trauma (Erb's palsy and fracture), and maternal trauma. RESULTS: The incidence of shoulder dystocia was 0.7% (39,280 total vaginal deliveries). Use of only two maneuvers, McRoberts and suprapubic pressure, resulted in resolution in 58% of cases. The addition of the Woods screw maneuver and/or delivery of the posterior arm was sufficient in all remaining cases. The rates of neonatal palsy and fracture, and maternal four-degree laceration, increased with the number of maneuvers. CONCLUSIONS: The McRoberts maneuver and suprapubic pressure should be first-line treatment for shoulder dystocia. More difficult and damaging maneuvers such as Woods screw and delivery of the posterior arm may be reserved for refractory cases. Additional maneuvers are rarely necessary for delivery. The number of maneuvers may serve as a measure of the severity of the shoulder dystocia.

Short-limb dwarfism and hypertrophic cardiomyopathy in a patient with paternal isodisomy 14: 45,XY,idic(14)(p11).

Uniparental disomy (UPD) has been shown to result in specific disorders either due to imprinting and/or homozygosity of mutant alleles. Here we present the findings in a child with paternal UPD14. Ultrasound evaluation was performed at 30 weeks of gestation because of abnormally large uterine size. Pertinent ultrasound findings included polyhydramnios, short limbs, abnormal position of hands, small thorax, and nonvisualization of the fetal stomach. Post-natally the infant was found to have a low birth weight, short birth length, contractures, short limbs, and a small thorax with upslanting ribs. Assisted ventilation and gastrostomy were required. At age 6 months, the infant required hospitalization for hypertrophic cardiomyopathy which responded to Atenolol. Initial cytogenetic studies demonstrated an apparently balanced de novo Robertsonian translocation involving chromosomes 14 and a karyotype designation of 45,XY,t(14q14q). No indication of mosaicism for trisomy 14 was observed in metaphase spreads prepared from peripheral blood lymphocytes or skin-derived fibroblasts. C-band and fluorescence in situ hybridization results demonstrated that the chromosome was dicentric. DNA analyses showed paternal uniparental isodisomy for chromosome 14. Based on the cytogenetic and DNA results a final karyotype designation of 45,XY,idic(14)(p11) was assigned to this infant with paternal isodisomy of chromosome 14.

Xrcc-1 expression during male meiosis in the mouse.

XRCC1 is involved in DNA strand-break repair, homologous recombination, and sister chromatid exchange and is expressed as a low-abundance mRNA with elevated expression in testis. The purpose of this study was to determine whether specific spermatogenic cell types have elevated Xrcc-1 expression and whether expression levels change in the testis with increased age. Northern blot analysis of mRNA prepared from testes of 15-, 25-, and 60-day-old mice revealed a single hybridizing band of 2.2 kb. Quantitative RNase protection assays revealed no changes in the level of Xrcc-1 expression in testis relative to DNA content among 6-, 12-, 18-, 24-, or 28-mo-old mice. Finally, reverse transcription coupled polymerase chain reaction amplification results demonstrated that Xrcc-1 expression is most abundant in pachytene spermatocytes and round spermatids with low expression in Sertoli cells, types A and B spermatogonia, preleptotene spermatocytes, and leptotene plus zygotene spermatocytes. The relatively abundant Xrcc-1 expression in pachytene spermatocytes and round spermatids suggests that Xrcc-1 is involved in DNA strand-break repair associated with meiotic recombination in addition to its previously implicated role in strand-break repair associated with base excision repair.

Intensified versus conventional management of gestational diabetes.

OBJECTIVE: We tested the hypothesis that intensified management of gestational diabetes mellitus on the basis of stringent glycemic control, verified glucose data, and adherence to an established criterion for insulin initiation results in near normoglycemia control and reduction of adverse outcomes. STUDY DESIGN: A prospective, population-based study compared the effect on perinatal outcome of conventional (n = 1316) and intensified (n = 1145) management. Group assignment was based on availability of memory-based reflectance meters at entry to the program. A contemporaneous randomized control group (nondiabetic, n = 4922) was selected. RESULTS: The diabetic groups were comparable in demographic characteristics and in factors associated with higher risk for adverse pregnancy outcome, such as previous macrosomia, previous gestational diabetes mellitus, and family history of diabetes. The control group was younger, less obese, and had a lower rate of previous macrosomia. The intensified management group had rates of macrosomia, cesarean section, metabolic complications, shoulder dystocia, stillbirth, neonatal intensive care unit days, and respiratory complications lower than those in the conventional management group and comparable to those of the nondiabetic controls. Other maternal complication rates, such as for preeclampsia, chronic hypertension, and infection, were similar for the three groups. Mean blood glucose levels were a good predictor of perinatal outcome. Gestational age at delivery, previous history of macrosomia, and overall mean blood glucose levels were the only significant predictors of birth weight percentile in both diabetic groups (logistic regression). CONCLUSION: The intensified management approach is significantly associated with enhanced perinatal outcome. This management strategy clarifies the relationship between glycemic control and neonatal outcome.