Incidence and Outcomes of Gestational Diabetes Mellitus Using the New International Association of Diabetes in Pregnancy Study Group Criteria in Hôpital Maisonneuve-Rosemont

Prevalence of gestational diabetes in the United States and Canada: a systematic review and meta-analysis

BACKGROUND

An understanding of the prevalence of gestational diabetes mellitus among pregnant women is essential at local, national and international level so that appropriate health care interventions can be planned, financed and delivered.

METHODS

A systematic review and meta-analysis of primary research reporting the prevalence of gestational diabetes mellitus in Canada or the United States were carried out according to Meta-analysis of Observational Studies in Epidemiology guidelines. Four electronic databases were systematically searched in June 2023 to identify articles that reported gestational diabetes mellitus prevalence using universal screening in pregnant women from eligible general population samples. Estimates were combined using a random effects model, and the effects of moderator variables analysed.

RESULTS

There were 36 separate samples of women or deliveries (total sample size 1,550,917). Overall mean prevalence of gestational diabetes mellitus was 6.9% (95% CI: 5.7-8.3); 13.7% (95% CI: 10.7-17.3) in studies using a one-step screening strategy, and 5.2% (95% CI: 4.4-6.1) in those using a two-step strategy. Heterogeneity in technical methods between studies produced differences in estimates, as did different diagnostic thresholds used.

CONCLUSIONS

The meta-analysis suggests a slightly higher prevalence of gestational diabetes mellitus in Canada and the United States, compared to Europe, but highlights the need for standardised protocols for estimating gestational diabetes mellitus prevalence.

Validation of Insurance Billing Codes for Monitoring Antenatal Screening

BACKGROUND

Prevalence statistics for pregnancy complications identified through screening such as gestational diabetes usually assume universal screening. However, rates of screening completion in pregnancy are not available in many birth registries or hospital databases. We validated screening-test completion by comparing public insurance laboratory and radiology billing records with medical records at three hospitals in British Columbia, Canada.

METHODS

We abstracted a random sample of 140 delivery medical records (2014-2019), and successfully linked 127 to valid provincial insurance billings and maternal-newborn registry data. We compared billing records for gestational diabetes screening, any ultrasound before 14 weeks gestational age, and Group B streptococcus screening during each pregnancy to the gold standard of medical records by calculating sensitivity and specificity, positive predictive value, negative predictive value, and prevalence with 95% confidence intervals (CIs).

RESULTS

Gestational diabetes screening (screened vs. unscreened) in billing records had a high sensitivity (98% [95% CI = 93, 100]) and specificity (>99% [95% CI = 86, 100]). The use of specific glucose screening approaches (two-step vs. one-step) were also well characterized by billing data. Other tests showed high sensitivity (ultrasound 97% [95% CI = 92, 99]; Group B streptococcus 96% [95% CI = 89, 99]) but lower negative predictive values (ultrasound 64% [95% CI = 33, 99]; Group B streptococcus 70% [95% CI = 40, 89]). Lower negative predictive values were due to the high prevalence of these screening tests in our sample.

CONCLUSIONS

Laboratory and radiology insurance billing codes accurately identified those who completed routine antenatal screening tests with relatively low false-positive rates.

Phosphatase and Tensin Homology Deletion Gene (PTEN) Regulates Fibroblast Precursor Cells Autophagy and Vascular Endothelial Growth Factor Signaling in Preeclampsia

Preeclampsia (PE) causes serious harm to the health of mothers and infants. PTEN regulates cell biological behaviors, but its role in preeclampsia have not been reported. Real time PCR and Western blot detected PTEN level in the placenta of PE patients and controls. Placental trophoblastderived cell line HTR8 was assigned into NC group, PTEN group and si-PTEN inhibitor group followed by measuring PTEN level, cell proliferation by MTT assay, cell invasion by Transwell, Caspase 3 activity, Beclin-1 and Atg-5 expression as well as PI3K/Akt/HIF-1α/VEGF signaling protein by Western blot. PTEN in PE patients was significantly downregulated (P < 0.05). Transfection of PTEN siRNA significantly down-regulated PTEN, promoted cell proliferation and invasion, reduced Caspase 3 activity, increased Beclin-1 and Atg-5, and PI3K/Akt/HIF-1α/VEGF protein expression (P < 0.05). Transfection of pcDNA 3.0-PTEN up-regulated PTEN and significantly reversed the above changes (P < 0.05). In conclusion, PTEN is reduced in PE and it can regulate pre-eclampsia trophoblast autophagy possibly through PI3K/Akt/HIF-1α/VEGF signaling, suggesting that PTEN can be a potential target for PE therapy.

Excessive gestational weight gain in early pregnancy and insufficient gestational weight gain in middle pregnancy increasing risk of gestational diabetes mellitus

Background:

Gestational weight gain (GWG) is associated with the risk of gestational diabetes mellitus (GDM). However, the effect of weight gain in different trimesters on the risk of GDM is unclear. This study aimed to evaluate the effect of GWG on GDM during different trimesters.

Methods:

A birth cohort study was conducted from 2017 to 2020 in Shenzhen, China. In total, 51,205 participants were included comprising two models (early pregnancy model and middle pregnancy model). Gestational weight (kg) was measured at each prenatal clinical visit using a standardized weight scale. Logistic regression analysis was used to assess the risk of GDM. Interaction analysis and mediation effect analysis were performed in the middle pregnancy model.

Results:

In the early pregnancy model, the risk of GDM was 0.858 times lower (95% confidence interval [CI]: 0.786, 0.937) with insufficient GWG (iGWG) and 1.201 times higher (95% CI: 1.097, 1.316) with excessive GWG after adjustment. In the middle pregnancy model, the risk of GDM associated with iGWG increased 1.595 times (95% CI: 1.418, 1.794) after adjustment; for excessive GWG, no significant difference was found (P = 0.223). Interaction analysis showed no interaction between GWG in early pregnancy (GWG-E) and GWG in middle pregnancy (GWG-M) (F = 1.268; P = 0.280). The mediation effect analysis indicated that GWG-M plays a partial mediating role, with an effect proportion of 14.9%.

Conclusions:

eGWG-E and iGWG-M are associated with an increased risk of GDM. Strict control of weight gain in early pregnancy is needed, and sufficient nutrition should be provided in middle pregnancy.

Trends in National Canadian Guideline Recommendations for the Screening and Diagnosis of Gestational Diabetes Mellitus over the Years: A Scoping Review

Canada's largest national obstetric and diabetology organizations have recommended various algorithms for the screening of gestational diabetes mellitus (GDM) over the years. Though uniformity across recommendations from clinical practice guidelines (CPGs) is desirable, historically, national guidelines from Diabetes Canada (DC) and the Society of Obstetricians and Gynaecologists of Canada (SOGC) have differed. Lack of consensus has led to variation in screening approaches, rendering precise ascertainment of GDM prevalence challenging. To highlight the reason and level of disparity in Canada, we conducted a scoping review of CPGs released by DC and the SOGC over the last thirty years and distributed a survey on screening practices among Canadian physicians. Earlier CPGs were based on expert opinion, leading to different recommendations from these organizations. However, as a result of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, disparities between DC and the SOGC no longer exist and many Canadian physicians have adopted their recent recommendations. Given that Canadian guidelines now recommend two different screening programs (one step vs. two step), lack of consensus on a single diagnostic threshold continues to exist, resulting in differing estimates of GDM prevalence. Our scoping review highlights these disparities and provides a step forward towards reaching a consensus on one unified threshold.