Gestational diabetes is a much debated condition in the medical world, and many studies carried out recently yielded divergent results as to the utility of the new screening criteria issued by the International Association of Diabetes and Pregnancy Study Group (IADSPG). The prevalence of diabetes has significantly increased over the past few years. This study’s aim was to clarify whether treating patients with "mild" gestational diabetes is beneficial.
We conducted a retrospective study analyzing materno-fetal complications in diabetic patients in 2008 and 2014, according to the former (Carpenter and Coustan criteria) and more recent (IADSPG criteria) standards for gestational diabetes screening. Patients were classified into subgroups in order to investigate the evolution of the complication prevalence between patients with only one pathological oral glucose tolerance test (OGTT) value in 2008 (untreated) and those with only one pathological OGTT value in 2014 (treated). This intermediate group was called "OGTT-1".
Compared to healthy patients, diabetic patients had an increased risk (P < 0.05) of caesarean section (28%), delivery induction (53%), respiratory distress (16%), and neonatal hypoglycemia (16%). Following the introduction of the new screening standards, the prevalence of diabetic patients increased from 3% to 14% in our center. Among all analyzed materno-fetal complications, only the risks of premature delivery (17.6% in 2008 and 2.8% in 2014) and of polyhydramnios (11.8% in 2008 and 0% in 2014) decreased for diabetic patients in 2014, when the new screening criteria were applied (P < 0.05). However, the instrumentation rate increased in 2014 (0% in 2008 and 18.1% in 2014) (P = 0.05). No significant differences were observed for the other studied complications. The rate of materno-fetal complications was not significantly higher among patients with ≥ 2 pathological OGTT values compared to those with only one pathological OGTT value ("OGTT-1" group). The odds ratios (OR) and relative risks (RR) even showed a trend towards a greater risk of instrumentation, macrosomia, neonatal intensive care unit (NICU) stay, and highrisk neonatal icterus among "OGTT-1" patients. Among "OGTT-1" patients, no significant differences were observed between 2008 (untreated) and 2014 (treated). However, the OR and RR indicated a decreased complication rate within the "OGTT1-2014" group for the risk of hypertensive disorders of pregnancy/preeclampsia, premature delivery, macrosomia, birth weight < P10, respiratory distress, hypoglycemia, NICU stay, and high-risk neonatal icterus.
The study does not allow concluding that treating "OGTT-1" patients has a statistically significant interest, since complications did not significantly decrease in 2014 as compared to 2008. Nevertheless, the OGTT-1 group was identified as a population at risk of materno-fetal morbidity, and a trend towards treatment seems to emerge from our results based on the OR and RR. A larger study should be conducted to confirm these hypotheses. The transition to the IADSPG standards resulted in a significant decrease in the rate of premature delivery and polyhydramnios among the 2014 diabetic patients and was associated with a trend towards a decrease in the other studied complications. The decreased complications among non-diabetic patients in 2014 also suggest that transferring "OGTT-1" patients from the "healthy" to the "pathological" group helped to reduce the morbidity of non-diabetic patients. Our observations are in favor of treating the OGTT-1 group.