Effectiveness of a screening protocol for gestational diabetes in pregnant Spanish women

Abstract

Objective. Screening for gestational diabetes mellitus (GDM) and its treatment can reduce health risks for the mother and child. This study estimated the prevalence of undetected GDM in Tenerife Island, to determine the rate of dropout from the diagnostic protocol and to identify the features of the protocol that reduced its effectiveness.Methods. We calculated GDM prevalence and the breaches of the diagnostic protocol out of 12,084 pregnant women who started the GDM detection program during 2004–2006. The prevalence of protocol breaches was used to estimate overall prevalence of GDM for the study population.Results. The overall prevalence of GDM was 6.4% (95% CI: 5.9–6.9%). Ten percent of them did not comply with the protocol. Noncompliant subjects were, on average, older (31.4 ± 5.7 vs. 30.0 ± 5.7 years, p < 0.001) and those with higher fasting blood glucose, 83 vs. 78 mg/dl (4.6 vs. 4.3 mmol/l) p < 0.001) than compliant subjects. About one third (30%) of the noncompliant women may be additional cases of GDM, which would increase the prevalence by 2.2% (95% CI: 1.9–2.5%) for an estimated total figure of 8.6% (95% CI: 8.1–9.1%).Conclusions. One out of every three cases of GDM may escape detection among women who do not complete the GDM screening protocol.