Rates of screening for diabetes remain low in the post-partum period with usual care; however, reminder letters sent to PCPs or patients (or both) improve adherence to screening guidelines. This follow-up survey study demonstrates that physicians and patients value the importance of screening for diabetes, identify the PCP as pivotal to screening, and appreciate a reminder strategy. However, there continue to be barriers in the health care system to screening for T2DM in new mothers with previous GDM, despite the self-reported perceived importance of screening.
There is widespread reluctance to order OGTTs, not only for those in the postpartum state but also in the nonpregnant population.21
The complexity and time required for an OGTT, the uncertain value of intervening when impaired glucose tolerance is identified, and the perceived cost all might influence the use of OGTTs. Up to 30% of women with previous GDM will be misdiagnosed using fasting glucose tests alone, and such tests will not identify glucose intolerance, limiting opportunities for intervention to prevent T2DM.8,10
An OGTT every 3 years might also be the most cost-effective way for diagnosing new cases in the postpartum period.22
The difficulties of completing an OGTT with a new infant, especially if breastfeeding, should not be minimized. However, only 9 of the 86 patients who took the test in our study found it difficult.
There is often fragmentation of care delivery during pregnancy and in the postpartum period. Women have their GDM screening through their obstetrics care providers, see internists or endocrinologists if their test results are abnormal, then return to their PCPs post partum. A diagnosis of GDM might not be communicated to the PCP, which precludes any proactive intervention. Patients strongly endorse the role of the PCP in postpartum screening, yet many do not visit their PCPs for their own care within the first year of giving birth.
Perception of personal risk is a critical factor in adherence to recommended health behaviour. Those most at risk might be least likely to return for screening.18
In US studies, women who had postpartum screening were more likely to attend their routine postpartum 6-week visits, have less severe GDM, and have lower body mass indexes.10,12,18
However, we did not identify these disparities in our study population. There are important differences between the Canadian and US health care systems, such as the discontinuation of Medicaid coverage 60 days after delivery in the United States, which limits generalizability of results across the border.12
Little is known about women’s risk perception of T2DM following GDM and its influence on postpartum screening. In our survey, both patients and PCPs recognized the importance of screening; however, patients who responded might have been those most interested in their health. In a 5-to 9-year follow-up study at our centre, only 1 out of 3 of women with previous GDM correctly identified her risk of T2DM as being substantially elevated.23
It might be that women recognize the association between GDM and T2DM, but do not perceive themselves to be at elevated risk.24
Evidence-based interventions are required to translate knowledge into action. Our delayed-reminder approach increased postpartum screening and was appreciated by patients and providers. Although not studied systematically, 1 article reported that rates of postpartum screening with OGTTs increased from 17% to 72% with introduction of a case manager system.10
There are no other studies assessing the effects of innovative methods to increase screening. With expansion of electronic health records and diabetes registries, the potential of automated reminders should be examined.
Our survey study is limited by the number and type of individuals who responded. Patients who did not receive reminders were less likely to answer the survey and are underrepresented in our sample, although the overall patient response rate was adequate (63%). Receiving a screening reminder might have increased awareness and thus interest in participating. Patients without PCPs were ineligible for the study; individuals without access to primary care face additional hurdles in receiving screening care. Further studies are required to examine the generalizability of our results.
Gestational diabetes presents a unique opportunity to predict future diabetes occurrence. There is an urgent need for effective screening and intervention strategies in this high-risk population. Primary care providers and patients value the importance of screening for diabetes, identify the PCP as pivotal to screening, and appreciate a reminder strategy.