Gestational diabetes mellitus (GDM) is defined as any degree of abnormal glucose results during pregnancy [1]. GDM is one of the most common medical complications of pregnancy and it is increasing in prevalence globally, due to the background of an increase in the rates of obesity in women of reproductive age and rise in maternal age [2]. Women with a history of GDM have an increased risk of developing impaired glucose regulation (IGR) [3, 4]. Approximately 50% of women with GDM developed diabetes within 5 years after their pregnancies [5]. Also, metabolic syndrome and cardiovascular diseases are commonly reported to be associated with GDM [6]. These long-term outcomes not only threaten the health of women but also increase the economic burden to the health care system. Therefore, it imperative to systematically manage GDM patients and to identify, intervene, and prevent these patients from developing a chronic disease.

The 6-week postpartum visit with a 75 g oral glucose tolerance testing (OGTT) is crucial for the long-term health of GDM women. Therefore, a plethora of clinical practice guidelines recommend postpartum glucose screening [7, 8, 9]. In China, women who failed to pass the 75 g OGTT postpartum (fasting $\ge$6.1 mmol/L, 30 min $\ge$11.1 mmol/L, 120 min $\ge$7.8 mmol/L) would be diagnosed with diabetes [9]. Studies have found that certain interventions may increase the screening rate such as reminding GDM patients of the importance of the screening [10, 11]. However, the screening rate is still inadequate worldwide: 13.1% in China and 40.85% in the USA [10, 11]. New social media platforms have become a convenient, fast, interactive, and extensive tool for information dissemination. The “Internet healthcare” model is very suitable for China’s large population and relative shortage of medical resources [12]. Smartphone applications promote a technological approach to support patient self-management and enhance communication between clinicians and GDM patients in the community and secondary care settings. Currently, there are more than 300,000 mobile health (mHealth) apps available for a broad range of medical disorders [13]. The mHealth apps for GDM are mainly used to record patient information such as blood glucose readings or diet, provide generic patient education or advice, and reduce adverse events by providing medication along with appointment alerts [14]. WeChat platform is one of the most popular message and social media apps in China, with registered accounts estimated to be over 1.1 billion. The WeChat platform rolls the functions of QQ, Facebook, Skype, and Instagram into one source. It is free and easy to use, which can send messages such as text, voice, and photos, and can create group chat, video conference, and location sharing. The characteristics of the WeChat platform make it an ideal app for GDM management. Previous studies have shown that the WeChat platform provides a feasible, effective, and sustainable management plan for chronic diseases such as obstructive pulmonary disease [15] and coronary artery disease [16]. The WeChat platform can deliver health text and video, which may elevate patients’ health awareness. Moreover, it also increases the efficacy of disease management when discharged from the hospital, which improves prognosis. Therefore, we hypothesized that the WeChat platform, which doctors could use to spread nutrition knowledge and remind GDM patients to be evaluated periodically, may help enhance the communication between GDM patients and doctors, and may improve the postpartum OGTT screening rate.

Research has shown that maternal age, body mass index (BMI), race/ethnicity, and family history are associated with the prevalence of GDM and type 2 diabetes mellitus (T2DM) [17]. This study aimed to (1) check the screen rate of the WeChat platform management in GDM women; (2) explore independent predictors of the completion rate of postpartum OGTT, and postpartum IGR via the WeChat platform management.

The prevalence of GDM has been increasing globally including China. In Tianjin, a cosmopolitan city in North China, the prevalence of GDM increased from 2.3% in 1999 to 8.1% in 2012 [4]. GDM has substantial implications for long-term maternal health including a 13-fold increased risk of GDM [22] in a subsequent pregnancy and a 10-fold higher risk of developing DM later in life as compared to those with normal glycemia level in pregnancy [3]. Given the global prevalence of metabolic diseases, GDM management should now shift to early postpartum prevention strategies to reduce the progression of GDM toward type 2 diabetes and address long-term maternal metabolic risks. Many clinical practice guidelines recommend screening for blood glucose in the postpartum period [7, 8]. Persistent hyperglycemia for the diagnosis of T2DM in the immediate postpartum period (within 1–3 days) is uncommon. Thus, delayed glucose testing is recommended to occur 4 to 12 weeks postpartum when IGT is detected in 17% to 23% of women with antecedent GDM pregnancies. The National Institute for Health and Care Excellence (NIHCE) endorses FPG testing at 6 to 13 weeks postpartum. This has the potential to increase the rate of missed diagnosis as up to 40% more women having T2DM using the 75 g OGTT as compared with FPG alone. Thus, the NIHCE recommends an abnormal screening FPG ($\ge$6.0 mmol/L) should be followed with a confirmatory test (second FPG, HbA1c, or OGTT). As the progression to T2DM is partly attributed to decreased insulin sensitivity and impaired beta-cell compensation in women with a history of GDM, women with GDM should receive continued follow-up if their glucose levels were normal during the 6-week postpartum screening. The American Diabetes Association (ADA) recommends diabetes testing every 1 to 3 years thereafter using HbA1c, FPG, or OGTT utilizing nonpregnant thresholds [23]. NIHCE echoes that women with increased postpartum glucose levels that are not diagnostic of diabetes should undergo annual testing, and advises annual HbA1c testing for women diagnosed with GDM who have negative postnatal diabetes screening [6].

Major organizations have proposed that GDM patients complete postpartum OGTT screening at 4–12 weeks postpartum as it is the most convenient evidence-based approach [9, 23]. Ideally, all GDM patients need to undergo an OGTT at their 6-week postpartum visit. Postpartum OGTT screening has the potential to identify individuals with IGT or IFG, which may be reversible [24]. Chang et al. [10] found that only 282 (13.1%) of 2152 Chinese GDM patients completed glucose screening after delivery. Researchers from USA found that 40.85% to 45% GDM patients finished postpartum glucose screening in the USA [11, 25]. A study from France showed that only 154 (38.1%) of 404 GDM patients participated in the postpartum OGTT [26]. A 13-year Italian cohort study found that only 26.3% of GDM women had a postpartum OGTT [27].

Many researchers are seeking ways to improve the postpartum glucose screening rate following GDM. Carson et al. [28] found that contacting patients proactively via phone calls, or postal reminders increased the postpartum testing rate from the average of 33% up to 60%. Another study found that phone calls from nutritionists reminding patients to attend postpartum visits increased postpartum glucose test rates (36% vs. 17%) [29]. DIAMIND study of Australia found that a short message service reminder significantly increased the attendance for postpartum OGTT, and mothers preferred to receive electronic reminders, particularly text messages, sent by the study team or their clinicians [30, 31]. It was also shown to be effective for the Kaiser Permanente Northwest (KPNW) GDM Care to use electronic medical record data and an electronic system automated reminder call [32]. In our study, we used WeChat as a platform to manage the follow-up issues for GDM patients. With the high usage rate of the WeChat platform in China, almost all GDM women are likely to use it. Our questionnaire distributed via the WeChat platform showed that 94.9% of the GDM patients understood the necessity of postpartum OGTT screening, and 73.9% of those were screened for OGTT 4–12 weeks after delivery. The percentage of postpartum glucose screening in our study was much higher than the other Chinese study which showed that only 13.1% of GDM patients completed glucose screening after delivery [18].

Stepwise logistic regression analysis showed that only two parameters “GDM history” and “delivery mode (cesarean section)” were significant. Women with a previous history of GDM were less likely to complete postpartum OGTT than those who did not have GDM (OR: 3.74, 95% CI: 1.97–7.08), and women who had a cesarean section were more likely to return to the hospital to complete postpartum OGTT than those with a vaginal delivery (OR: 1.83, 95% CI:1.02–3.28). It has been suggested that enhancing education provided to women with a history of GDM may improve postpartum OGTT screening rates. Our results are similar to the findings recently published by Hunt et al. [33] who reported that women who failed to return for postpartum glucose testing were more likely to report prior GDM. However, in contrast to our results, the factors they identified as being associated with postpartum glucose testing were public insurance [19], older age, nulliparity, higher income or education [34], lower diagnostic glucose levels, and not requiring insulin during pregnancy [33]. Different ethnicities, and economic abilities of patients and inclusion criteria of studies may lead to differences in the findings.

The other principal finding in our study was that those who used insulin during pregnancy and those who had a cesarean section had a higher rate of abnormal postpartum OGTT results. This may be due to the fact that those who used insulin treatment during pregnancy or had a cesarean section had a higher glucose level during pregnancy, making it more difficult to return to normal glucose levels after delivery.

Our study did not use a control group to compare the rate of postpartum blood glucose screening with and without WeChat-based management. The source of nutrition advice provides limited information on the patient’s nutrition knowledge. In addition, due to the limitation of experimental samples, our conclusions may not comprehensively reflect all situations, and further expansion of the sample size is needed to promote the generalizability of the findings. All participants received questionnaires to ask whether they had completed their screening in the study. This part of the study could also further increase screening rates independently of the WeChat messaging, which may be a confounding factor. Follow-up via hospital records may avoid this issue. Despite the limitations, our study also has notable strengths.

Considering the close relationship between GDM and chronic diseases like T2DM, identifying and implementing interventions to decrease the incidence of associated health complications is a priority [6]. Previous study has shown that breastfeeding, postpartum healthy dietary intake and regular exercise can reduce progression to diabetes for women with a history of GDM [6]. In a 10 years follow-up observation, intensive lifestyle modifications along with the use of metformin were found to reduce progression to T2DM significantly [6]. Future studies should explore the utility of social medial platforms for enhancing nutrition knowledge and GDM management.

The WeChat messaging platform may be a useful tool to enhance postpartum OGTT screening among women with GDM. Women who failed to return for postpartum glucose screening (PGS) were more likely to report prior GDM than women who returned for PGS. Women who had postpartum IGR were more likely to use insulin treatment during pregnancy and more likely to deliver by cesarean section compared to women who had normal postpartum glucose results.

The data that support the findings of this study are available on request from the corresponding author Min Liu upon reasonable request.

Study concepts were prepared by ML and YFL. The study was designed by HL. Data acquisition was performed by HYP and CXC. Quality control of data and algorithms was carried out by MW and CMM. Data analysis and interpretation was conducted by GF and JRW. Statistical analysis was performed by HN and JYW. The manuscript was prepared and edited by HL. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript.

All subjects gave their informed consent for inclusion before they participated in the study. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Institutional Review Boards of the Third Xiangya Hospital, Central South University (No: 2020-S262).

We would like to express our gratitude to all those who helped us during the writing of this manuscript. Thanks to all the peer reviewers for their opinions and suggestions.

This work was supported by the Natural Science Foundation of Hunan Province (No. 2022JJ40749), the Project of Scientific Research Plan of Health Committee of Hunan Province (202203065334), and the Scientific Research Project of Hunan Provincial Health Commission (No. B2017032).

The authors declare no conflict of interest.