Evaluation of the Implementation of the 75-gram, 2-hour Glucose Tolerance Test in a Nurse-midwifery Practice

Abstract

Purpose/Aim Despite recent attempts at achieving international consensus concerning screening criteria for gestational diabetes, conflicting opinions and strategies persist. A clinical inquiry project described the implementation of the one-step, 75-gram, 2-hour glucose tolerance test (GTT) in a nurse-midwifery practice at an academic health center. Research Questions and/or Hypotheses The 4 aims of the inquiry project were to describe characteristics and outcomes of nurse-midwifery patients diagnosed with gestational diabetes using the newly implemented screening criteria, including: 1) demographic characteristics, 2) select antepartum measures, 3) select maternal and newborn outcomes, and 4) select indicators of utilization of resources. Significance/Background This inquiry project is the first known description of the implementation of the one-step, 75-gram, 2-hour GTT in a national nurse-midwifery population. Methods All nurse-midwifery patients who had been diagnosed with gestational diabetes using the International Association of Diabetes and Pregnancy Study Groups Consensus Panel's criteria between June 1, 2012 and February 28, 2013 were included. Local IRB approval was obtained. Descriptive statistics were used to report the data. Findings Thirty-three women were diagnosed with gestational diabetes. The gestational diabetes prevalence rate increased from approximately 4.6% to 15.6%. Forty-six percent of the women diagnosed with gestational diabetes had risk factors and were screened at less than 17 weeks’ gestation. Forty-seven percent of these women were diagnosed with gestational diabetes that required medication (A2GDM) and transferred to the perinatal diabetes clinic. Twenty-eight women had given birth by the time of the analysis. Twenty-nine percent (n = 8) were induced for gestational diabetes-related indications. One woman required insulin in labor. One preterm birth at 36 weeks’ gestation was not attributed to gestational diabetes. Thirty-two percent (n = 9) had previous cesarean births. There were 4 repeat cesarean births, 2 of which were for arrest of labor and 2 for fetal intolerance of labor. The unscheduled cesarean birth rate, including those who labored with a past history of cesarean, was 21.4% (n = 6). The mean (SD) infant birth weight was 3553 (477) g. There were no cases of shoulder dystocia, birth injuries, neonatal hypoglycemia, or infant-mother separation. Discussion A descriptive summary revealed a substantial increase in the prevalence rate in this nurse-midwifery population. Maternal diagnosis and outcomes varied by risk factor status. Neonatal outcomes were overwhelmingly normal. Utilization of resources was highest among women with A2GDM. The analysis is limited by a small sample size and provides a basis for future studies of screening criteria for gestational diabetes in the nurse-midwifery population.