Insulin requirements throughout pregnancy in women with type 1 diabetes mellitus: three changes of direction

Provider Perspective on Automated Insulin Devices in Pregnancy and Considerations for Implementation in Clinical Practice

Pregnancy in people with type 1 diabetes mellitus (T1D) is well-known to be linked to adverse maternal and neonatal outcomes. Although advancements in diabetes technology, especially hybrid closed-loop (HCL) and advanced hybrid closed-loop (AHCL) systems, have greatly enhanced management for nonpregnant individuals with T1D, pregnant patients still represent a high-risk group that requires further research. Existing trials have shown mixed data in terms of clinically meaningful benefits in glycemic control, but these may be specific to the closed-loop system. Currently, there is one AHCL system approved and available for use in pregnancies complicated by diabetes in the United Kingdom, Europe, and Australia. However, there are no Food and Drug Administration (FDA)-approved closed-loop systems for use during pregnancy in the United States. Existing HCL/AHCL system use is off-label for pregnancy in the United States and often requires assistive techniques to target the tighter glucose levels needed during pregnancy. For patients struggling on multiple daily injections (MDIs) or sensor-augmented pump therapy (SAPT), studies have shown that HCL/AHCLs can reduce the burden of care and enable some people to achieve tighter glucose levels. This review aims to provide an overview of the existing evidence of closed-loop systems in pregnancies complicated by T1D and to discuss their implications and considerations with system use.

Hybrid closed loop insulin therapy versus standard therapy in pregnant women with type 1 diabetes: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

We aimed to explore the efficacy and safety of hybrid closed loop (HCL) systems compared to standard care (SC) in pregnant women with Type 1 Diabetes Mellitus (T1DM), pooling results from randomized controlled trials (RCTs).

DATA SOURCES

We searched through multiple databases like PubMed, Cochrane, Embase, Web of Science, and Clinicaltrials.gov etc. from inception to September 2024 and found six relevant studies after screening.

STUDY ELIGIBILITY CRITERIA

We included studies that were (1) RCTs; with patient population (2) pregnant patients with type 1 diabetes; intervention group receiving (3) HCL and control group receiving (4) SC; while reporting (5) outcomes of interest (endpoints). We pooled results pertaining to primary outcomes; time in range (TIR), nocturnal time in range (nTIR), and HbA1c; and relevant secondary outcomes.

STUDY APPRAISAL AND SYNTHESIS METHODS

We used Rob 2: A revised Cochrane risk-of-bias tool for randomized trials for quality assessment of the included RCTs. We employed the DerSimonian-Laird random effects model using review manager 5.4 to analyze the pooled estimates and reported results as risk ratio; for dichotomous outcomes; or mean difference; for continuous outcomes.

RESULTS

Five RCTs (n = 274) with disparate populations were narrowed down for analysis. Pooled estimates for TIR (MD 4.95 %;-0.56 to 10.49)and HbA1c% (MD 0.09; -0.44 to 0.63) were statistically non-significant, while estimates for nTIR (MD 11.16 %; 7.15 to 15.15), % time < 63 mg/dL (MD -0.78; -1.36 to -0.20), % of time < 54 mg/dL (MD -0.22; -0.40 to -0.03), low blood glucose index (LBGI) (MD -0.30; -0.54 to -0.06), and glucose standard deviation (MD -3.05; -6.06 to -0.04) favored HCL over SC. No significant between-group differences were found in other secondary outcomes: % of time >140 mg/dL, % of time >180 mg/dL, mean glucose level, rate of serious adverse events, cesarian delivery, and severe hypoglycemia.

CONCLUSIONS

HCL systems can improve glycemic control in pregnant women with T1DM with a tolerable adverse event profile, however more research is needed to draw a definitive conclusion.

Automated insulin delivery in pregnant women with type 1 diabetes mellitus: a systematic review and meta-analysis

AIMS

To assess the efficacy and safety of automated insulin delivery (AID) systems compared to standard care in managing glycaemic control during pregnancy in women with Type 1 Diabetes Mellitus (T1DM).

METHODS

We searched MEDLINE, Cochrane Library, registries and conference abstracts up to June 2024 for randomized controlled trials (RCTs) and observational studies comparing AID to standard care in pregnant women with T1DM. We conducted random effects meta-analyses for % of 24-h time in range of 63-140 mg/dL (TIR), time in hyperglycaemia (> 140 mg/dl and > 180 mg/dL), hypoglycaemia (< 63 mg/dl and < 54 mg/dL), total insulin dose (units/kg/day), glycemic variability (%), changes in HbA1c (%), maternal and fetal outcomes.

RESULTS

Thirteen studies (450 participants) were included. AID significantly increased TIR (Mean difference, MD 7.01%, 95% CI 3.72-10.30) and reduced time in hyperglycaemia > 140 mg/dL and > 180 mg/dL (MD - 5.09%, 95% CI - 9.41 to - 0.78 and MD - 2.44%, 95% CI - 4.69 to - 0.20, respectively). Additionally, glycaemic variability was significantly reduced (MD - 1.66%, 95% CI - 2.73 to - 0.58). Other outcomes did not differ significantly.

CONCLUSION

AID systems effectively improve glycaemic control during pregnancy in women with T1DM by increasing TIR and reducing hyperglycaemia without any observed adverse short-term effects on maternal and fetal outcomes.

Switching to insulin lispro U-200 in a pregnant woman using a 780G advanced hybrid closed-loop led to a rapid improvement in glucose metrics

Maintaining tight glucose levels during pregnancy is crucial and challenging. We describe a pregnant woman with type 1 diabetes and obesity, treated with an advanced hybrid closed-loop MiniMed 780G since pre-pregnancy, who displayed a sustained improvement in her glucometrics after switching to lispro U-200.

Trends in and characteristics of drug overdose morbidity among pregnant and postpartum individuals in California, 2010-2018

Fatal drug overdoses among pregnant and postpartum individuals have risen dramatically over the past 10 years. Trends in and characteristics of nonfatal drug overdoses in this population, however, remain unknown, despite the importance of this outcome for maternal and infant health. We used statewide, longitudinally linked hospital and emergency department administrative claims data from California to characterize the incidence, trends, drug type involvement, and sociodemographic disparities in pregnancy-associated drug overdose between 2010 and 2019. Generalized linear models accounting for multiple deliveries per individual were used to test for trends; descriptive statistics were used for other study analyses. Of California individuals with a live delivery between 2010 and 2018, approximately 0.2% had a pregnancy-associated drug overdose. Nonfatal overdoses were nearly 60 times more common than fatal overdoses. Incidence of overdoses involving stimulants increased in frequency, while incidence of overdoses involving sedative/hypnotic drugs and psychotropic medications decreased in frequency. Risk of overdose was substantially higher among delivering individuals who were young, non-Hispanic Black, Medicaid patients, or who lived in nonmetropolitan areas. Ongoing public health surveillance of pregnancy-associated nonfatal drug overdose events and clinical interventions to reduce these events are critical for prevention efforts.

Impact of continuous glucose monitoring on pregnancy outcomes in women with pregestational diabetes

AIMS

This study aims to evaluate the impact of continuous glucose monitoring (CGM) on pregnancy outcomes in women with pregestational diabetes mellitus (PGDM).

METHODS

A retrospective cohort study was conducted on 387 pregnant women with PGDM at Virgen del Rocío University Hospital in Seville, spanning from 2016 to 2022. The patients were categorized into two groups: 212 women who used continuous glucose monitoring (CGM) and 175 women who self-monitoring of blood glucose (SMBG). The study evaluated maternal characteristics, pregnancy complications, delivery methods, neonatal outcomes, and congenital anomalies.

RESULTS

The CGM group exhibited lower weight gain during pregnancy (9.6 kg vs. 10.0 kg, p = 0.02) and required fewer prenatal visits (7 vs. 8, p = 0.01). The rate of cesarean sections was significantly lower in the CGM group (53.1% vs. 58.2%, p = 0.03), and the incidence of macrosomia was reduced (12.9% vs. 22.2%, p = 0.04). There were no significant differences in congenital anomalies, intrauterine fetal deaths, or neonatal deaths between the groups.

CONCLUSIONS

CGM in pregnant women with PGDM is associated with better pregnancy outcomes, including reduced cesarean section rates and lower incidence of macrosomia. These findings support the wider implementation of CGM for improved maternal and fetal health in PGDM pregnancies.

Sensor-derived glycaemic metrics in pregnant women with type 1 diabetes randomised to faster acting insulin aspart or insulin aspart-A secondary analysis of the CopenFast trial

AIMS

We compared sensor-derived glycaemic metrics in pregnant women with type 1 diabetes (T1D) randomised to faster acting insulin aspart (faster aspart) or insulin aspart (IAsp).

METHODS

A pre-planned secondary analysis of the CopenFast trial included women with T1D using intermittently scanned continuous glucose monitoring (isCGM) during pregnancy. Glycaemic metrics, including time in range (TIRp, 3.5-7.8 mmol/L) and time below range in pregnancy (TBRp, <3.5 mmol/L), were evaluated in the intervals: from randomisation (median 9.5 weeks, interquartile range 9.0-11.0) to 21 weeks, from 22 to 33 weeks and from 34 to 37 weeks.

RESULTS

In total, 113 (91%) of 124 women using isCGM in the original trial were included. At randomisation, glycaemic metrics were comparable in both groups. Women randomised to faster aspart achieved higher TIRp from 22 to 33 weeks (estimated treatment difference 5.1% [95% confidence interval 0.3; 9.7], p = 0.04) and mean TIRp >70% from randomisation to 21 weeks onwards, while this was achieved after 34 weeks in women randomised to IAsp. TBRp remained stable around 4% throughout pregnancy in both groups. One (2%) versus 5 (9%) experienced ≥1 severe hypoglycaemic event (odds ratio 0.93 [-0.2; -0.01], p = 0.04). Infant birthweight standard deviation score was lower in the faster aspart group (estimated treatment difference -0.5 [-0.9; -0.03], p = 0.04); however, this attenuated when adjusting for parity (p = 0.10).

CONCLUSIONS

Women using faster aspart achieved more TIRp and experienced less severe hypoglycaemia compared to women using IAsp. Infant birthweight was lower and thereby more appropriate in the faster aspart group; however, this attenuated when adjusting for parity.

15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2025

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Approach to Altered Mental Status in Pregnancy and Postpartum

The evaluation and diagnosis of altered mental status in the pregnant or postpartum patient largely parallels the approach used for any other patient; however, there are several critical differences including that some neuroobstetric diagnoses require emergent delivery of the fetus. Being familiar with the physiological changes and medical complications of pregnancy and delivery is therefore essential. This review first addresses pregnancy-specific disorders that may result in altered mental status, such as the hypertensive disorders of pregnancy and pregnancy-related metabolic and endocrinopathies. The focus then shifts to the complex physiologic changes in pregnancy and how these changes contribute to the distinct epidemiology of pregnancy-related cerebrovascular complications like intracranial hemorrhage, ischemic stroke, and reversible cerebral vasoconstriction syndrome. Medical disorders that are not unique to pregnancy, such as infections and autoimmune conditions, may present de novo or worsen during pregnancy and the peripartum period and require a thoughtful approach to diagnosis and management. Finally, the unique nervous system complications of obstetric anesthesia are explored. In each section, there is a focus not only on diagnosis and syndrome recognition but also on the emergent treatment needed to reverse these complications, bearing in mind the unique physiology of the pregnant patient.

Use of Automated Insulin Delivery in Pregnancies Complicated by Type 1 Diabetes

Background: Diabetes during pregnancy is associated with significant maternal and foetal health risks. Insulin requirements also change during pregnancy. This necessitates careful and effective management of diabetes. Although commonly used in clinical practice, the US Food and Drug Administration (FDA)-approved algorithms for automated insulin delivery (AID) systems do not have pregnancy-specific glycaemic targets. This review aims to evaluate the safety and efficacy of AID systems in reaching glycaemic targets in pregnant women with type 1 diabetes (T1D). Methods: In this retrospective case review, six pregnant women with T1D used three types of AID systems. Two patients used Omnipod 5, two patients used Control-I Q and two patients used Do-I t-Yourself (DIY) Loop. Results: Across trimesters, the two patients using Omnipod 5 had an average time in range (TIR) of 68 and 82%. Patients using Control-I Q had an average TIR of 77 and 69%. Both the patients using DIY Loop had an average TIR of 85%. Hypoglycaemia occurrence was minimal. Additionally, four of the six patients had uncomplicated vaginal deliveries in their third trimester, and four of the six patients achieved guideline-r ecommended TIR targets. Birth complications for the other two patients were resolved shortly after birth. Throughout the pregnancies, insulin needs approximately doubled. Conclusions: AID systems can achieve near-desired glycaemic targets with minimal hypoglycaemia in pregnant women with T1D. Randomized controlled trials are needed to confirm these findings and to win FDA indications in pregnancy.

Updates in the Management of Type 1 Diabetes in Pregnancy

The care of pregnant individuals with type 1 diabetes mellitus has experienced significant advancements in recent years. Preconception counseling has re-emerged as a core dimension of management. Continuous glucose monitoring plays an increasingly useful and beneficial role in gestational glycemic monitoring, a practice informed by improved maternofetal outcomes. While studies have not shown that continuous subcutaneous insulin infusion is superior to multiple daily injections of insulin for glycemic control, recent work has signaled that hybrid closed-loop systems with pregnancy-specific targets could meaningfully improve glycemic control and potentially ameliorate maternofetal outcomes while reducing self-care burden.

Type 1 Diabetes and Pregnancy: Challenges in Glycemic Control and Maternal-Fetal Outcomes

Managing type 1 diabetes during pregnancy presents significant challenges due to physiological and hormonal changes. These factors contribute to major changes in insulin sensitivity, complicating efforts to achieve and sustain optimal blood glucose levels. Poorly controlled glucose levels during pregnancy can result in diabetic embryopathy and elevate the risks of maternal complications such as hypertensive disorders and diabetic ketoacidosis. Fetal complications may include preterm birth, fetal demise, and admission to neonatal intensive care units. It is essential to recognize that there is no universal approach to managing glycemic control in pregnant women with T1DM and care should be individualized. Effective management requires a multidisciplinary approach involving regular monitoring, adjustments in insulin therapy, dietary modifications, and consistent prenatal care. Continuous glucose monitoring has emerged as a valuable tool for real-time glucose monitoring, facilitating tighter glycemic control. Education and support for self-management are important in addressing these challenges. Future developments in technology and personalized approaches to care show promising potential for advancing diabetes management during pregnancy. This provides a comprehensive overview of current literature on the challenges with the management of T1DM during pregnancy, focusing on its impact on maternal and neonatal outcomes and highlighting effective strategies for achieving optimal glycemic control.

A sensor-augmented pump with a predictive low-glucose suspend system could lead to an optimal time in target range during pregnancy in Japanese women with type 1 diabetes

Introduction

It is challenging for pregnant women with type 1 diabetes to maintain optimum glucose level to attain good neonatal outcomes. This study evaluated the efficacy of sensor-augmented insulin pump (SAP) with a predictive low-glucose suspend (PLGS) system in pregnant Japanese women with type 1 diabetes.

Materials and methods

SAP with PLGS was used in 11 of the 22 women with type 1 diabetes who delivered between 2011 and 2021 at the two medical institutions in Japan. Glucose management, insulin delivery suspension time (IST) and neonatal outcomes were retrospectively studied.

Results

In SAP with PLGS cases (n = 11), average glycated hemoglobin levels were < 6.5% throughout the pregnancy, and the time in range (TIR, 63-140 mg/dl) was > 70% in the second and third trimesters. PLGS was safely used without inducing ketoacidosis. Positive correlation was observed between IST and TIR (r = 0.62, p < 0.01). Negative correlation was observed between IST and time below range (TBR) (r =  - 0.40, p = 0.02), and IST and time above range (TAR) (r =  - 0.45, p = 0.01). Total daily insulin dose was adequately increased without increasing hypoglycemia. There was only one heavy-for-date HFD) infant among the 11 newborns in SAP with PLGS cases. In cases without SAP (n = 11), target glycemic levels were difficult to achieve and there were 5 HFD infants among the 11 newborns.

Conclusion

SAP with PLGS was safely and effectively used in pregnant women with type 1 diabetes to achieve target glucose levels without increasing the risk of hypoglycemia, which may have led to good neonatal outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-024-00716-7.

Comparing advanced hybrid closed loop therapy and standard insulin therapy in pregnant women with type 1 diabetes (CRISTAL): a parallel-group, open-label, randomised controlled trial

BACKGROUND

Advanced hybrid closed loop (AHCL) therapy can improve glycaemic control in pregnant women with type 1 diabetes. However, data are needed on the efficacy and safety of AHCL systems as these systems, such as the MiniMed 780G, are not currently approved for use in pregnant women. We aimed to investigate whether the MiniMed 780G can improve glycaemic control with less hypoglycaemia in pregnant women with type 1 diabetes.

METHODS

CRISTAL was a double-arm, parallel-group, open-label, randomised controlled trial conducted in secondary and tertiary care specialist endocrinology centres at 12 hospitals (11 in Belgium and one in the Netherlands). Pregnant women aged 18-45 years with type 1 diabetes were randomly assigned (1:1) to AHCL therapy (MiniMed 780G) or standard insulin therapy (standard of care) at a median of 10·1 (IQR 8·6-11·6) weeks of gestation. Randomisation was done centrally with minimisation dependent on baseline HbA1c, insulin administration method, and centre. Participants and study teams were not masked to group allocation. The primary outcome was proportion of time spent in the pregnancy-specific target glucose range (3·5-7·8 mmol/L), measured by continuous glucose monitoring (CGM) at 14-17 weeks, 20-23 weeks, 26-29 weeks, and 33-36 weeks. Key secondary outcomes were overnight time in target range, and time below glucose range (<3·5 mmol/L) overall and overnight. Analyses were conducted on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov (NCT04520971).

FINDINGS

Between Jan 15, 2021 and Sept 30, 2022, 101 participants were screened, and 95 were randomly assigned to AHCL therapy (n=46) or standard insulin therapy (n=49). 43 patients assigned to AHCL therapy and 46 assigned to standard insulin therapy completed the study. At baseline, 91 (95·8%) participants used insulin pumps, and the mean HbA1c was 6·5% (SD 0·6). The mean proportion of time spent in the target range (averaged over four time periods) was 66·5% (SD 10·0) in the AHCL therapy group compared with 63·2% (12·4) in the standard insulin therapy group (adjusted mean difference 1·88 percentage points [95% CI -0·82 to 4·58], p=0·17). Overnight time in the target range was higher (adjusted mean difference 6·58 percentage points [95% CI 2·31 to 10·85], p=0·0026), and time below range overall (adjusted mean difference -1·34 percentage points [95% CI, -2·19 to -0·49], p=0·0020) and overnight (adjusted mean difference -1·86 percentage points [95% CI -2·90 to -0·81], p=0·0005) were lower with AHCL therapy than with standard insulin therapy. Participants assigned to AHCL therapy reported higher treatment satisfaction. No unanticipated safety events occurred with AHCL therapy.

INTERPRETATION

In pregnant women starting with tighter glycaemic control, AHCL therapy did not improve overall time in target range but improved overnight time in target range, reduced time below range, and improved treatment satisfaction. These data suggest that the MiniMed 780G can be safely used in pregnancy and provides some additional benefits compared with standard insulin therapy; however, it will be important to refine the algorithm to better align with pregnancy requirements.

FUNDING

Diabetes Liga Research Fund and Medtronic.

Placental IGFBP1 levels during early pregnancy and the risk of insulin resistance and gestational diabetes

Reduced insulin sensitivity (insulin resistance) is a hallmark of normal physiology in late pregnancy and also underlies gestational diabetes mellitus (GDM). We conducted transcriptomic profiling of 434 human placentas and identified a positive association between insulin-like growth factor binding protein 1 gene (IGFBP1) expression in the placenta and insulin sensitivity at ~26 weeks gestation. Circulating IGFBP1 protein levels rose over the course of pregnancy and declined postpartum, which, together with high gene expression levels in our placenta samples, suggests a placental or decidual source. Higher circulating IGFBP1 levels were associated with greater insulin sensitivity (lesser insulin resistance) at ~26 weeks gestation in the same cohort and in two additional pregnancy cohorts. In addition, low circulating IGFBP1 levels in early pregnancy predicted subsequent GDM diagnosis in two cohorts of pregnant women. These results implicate IGFBP1 in the glycemic physiology of pregnancy and suggest a role for placental IGFBP1 deficiency in GDM pathogenesis.

Continuous glucose monitoring metrics in pregnancy with type 1 diabetes mellitus

Managing diabetes during pregnancy is challenging, given the significant risk it poses for both maternal and foetal health outcomes. While traditional methods involve capillary self-monitoring of blood glucose level monitoring and periodic HbA1c tests, the advent of continuous glucose monitoring (CGM) systems has revolutionized the approach. These devices offer a safe and reliable means of tracking glucose levels in real-time, benefiting both women with diabetes during pregnancy and the healthcare providers. Moreover, CGM systems have shown a low rate of side effects and high feasibility when used in pregnancies complicated by diabetes, especially when paired with continuous subcutaneous insulin infusion pump as hybrid closed loop device. Such a combined approach has been demonstrated to improve overall blood sugar control, lessen the occurrence of preeclampsia and neonatal hypoglycaemia, and minimize the duration of neonatal intensive care unit stays. This paper aims to offer a comprehensive evaluation of CGM metrics specifically tailored for pregnancies impacted by type 1 diabetes mellitus.

Use of Advanced Hybrid Closed-Loop System during Pregnancy: Strengths and Limitations of Achieving a Tight Glycemic Control

Background: Pregnant women with type 1 diabetes mellitus (T1DM) face an elevated risk of complications for both themselves and their newborns. Experts recommend strict glycemic control. The advanced hybrid closed-loop (AHCL) system, though not officially approved for pregnant T1DM patients, is promising for optimal glycemic control. Methods: We collected CGM metrics, HbA1c levels, insulin pump settings, and doses from a 33-year-old pregnant woman with 23-year history of T1DM from the 6th week of gestation to birth. She was initially on continuous insulin pump therapy with CGM and switched to the AHCL system (MiniMedTM 780G, Medtronic, Northridge, CA, USA) between weeks 13 and 14. Results: The AHCL system improved glycemic control from weeks 14 to 26, achieving international guidelines with TIR = 72%, TAR = 24%, TBR = 4%. At week 30, TIR was 66%, TAR 31%. By altering diet and adding 'fake carbohydrates', she maintained TIR ≥ 70%, TBR ≤ 4%, TAR ≤ 26% from week 34 to birth. A healthy 4 kg, 53 cm baby boy was born at week 38. Conclusions: The use of the AHCL system holds significant promise for improving glycemic control in pregnancy. Optimal glycemic control with MiniMedTM 780G in pregnancy requires accurate carbohydrate counting, specific timing of insulin doses in relation to meal consumption and dietary choices that reduce the glycemic load of meals continue to be crucial factors in achieving optimal glycemic control during pregnancy using the MiniMedTM 780G system. Further research and clinical studies are needed to explore the full potential of these advanced systems in managing T1DM during pregnancy and optimizing maternal and neonatal outcomes.

Gestational weight gain in women with type 1 and type 2 diabetes mellitus is related to both general and diabetes-related clinical characteristics

PURPOSE

To assess predictors of gestational weight gain (GWG), according to the Institute of Medicine (IOM) 2009, in women with type 1 and type 2 diabetes.

METHODS

This was a retrospective cohort study conducted at a tertiary center. GWG based on the IOM was assessed both uncorrected and corrected for gestational age. General and diabetes-related clinical characteristics were analyzed as predictors.

RESULTS

We evaluated 633 pregnant women with type 1 and type 2 diabetes. GWG uncorrected for gestational age was inadequate (iGWG) in 20.4%, adequate in 37.1%, and excessive (eGWG) in 42.5% of the women. Predictors included general (height, prepregnancy body mass index category, and multiple pregnancy) and diabetes-related clinical characteristics. Neuropathy and follow-up length were associated with iGWG (odds ratio (OR) 3.00, 95% CI 1.22-7.37; OR 0.92, 95% CI 0.86-0.97, respectively), while pump use and third-trimester insulin dose were associated with eGWG (OR 1.68, 95% CI 1.07-2.66; OR 3.64, 95% CI 1.88-7.06, respectively). Independent predictors for corrected GWG and sensitivity analyses also included general and diabetes-related clinical characteristics.

CONCLUSION

In this cohort of women with type 1 and type 2 diabetes, non-adequate GWG was common, mainly due to eGWG, and associated clinical characteristics were both general and diabetes-related. Current clinical care of these women during pregnancy may favor weight gain.

Effect of artificial pancreas system use on glycaemic control among pregnant women with type 1 diabetes mellitus: A meta-analysis of randomized controlled trials

AIM

To assess the efficacy of artificial pancreas systems (APS) use among pregnant women with type 1 diabetes mellitus (T1DM) by conducting a meta-analysis.

METHODS

We searched five databases, including EMBASE, Web of Science, PubMed, Cochrane Library and SCOPUS, for literature on APS use among pregnant women with T1DM before October 9, 2023. The primary endpoint was 24-hour time in range (TIR; 3.5-7.8 mmol/L). Secondary endpoints included glycaemic metrics for 24-hour (mean blood glucose [MBG], time above range [TAR], time below range [TBR]), and overnight TIR and TBR.

RESULTS

We identified four randomized controlled trials involving 164 participants; one study with 16 participants focused on overnight APS use, and the other three focused on 24-hour APS use. Compared with standard care, APS exhibited a favourable effect on 24-hour TIR (standard mean difference [SMD] = 0.53, 95% confidence interval [CI] 0.25, 0.80, P < 0.001), overnight TIR (SMD = 0.67, 95% CI 0.39, 0.95, P < 0.001), and overnight TBR (<3.5 mmol/L; SMD = -0.49, 95% CI -0.77, -0.21 P < 0.001), while there was no significant difference in 24-hour TAR, 24-hour TBR, or MBG between the two groups. We further conducted subgroup analyses after removing the trial focused on overnight APS use and showed that 24-hour APS use reduced not only the 24-hour TIR (SMD = 0.41, 95% CI 0.12, 0.71; P = 0.007) but also the 24-hour TBR (<2.8 mmol/L; SMD = -0.77, 95% CI -1.32, -0.23, P = 0.006).

CONCLUSION

Our findings suggest that APS might improve 24-hour TIR and overnight glycaemic control, and 24-hour APS use also significantly reduced 24-hour TBR (2.8 mmol/L) among pregnant women with T1DM.

15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2024

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

A Randomized Trial of Closed-Loop Insulin Delivery Postpartum in Type 1 Diabetes

OBJECTIVE

This study aimed to evaluate the efficacy of closed-loop insulin delivery postpartum.

RESEARCH DESIGN AND METHODS

In this open-label, randomized controlled trial, postpartum individuals with type 1 diabetes were randomized to hybrid closed-loop insulin delivery with the MiniMed 670G/770G system in automode or sensor-augmented pump therapy in the first 12-weeks postpartum followed by a continuation phase with closed-loop insulin delivery for all until 24 weeks postpartum.

RESULTS

Eighteen participants (mean ± SD age 32 ± 3.5 years, diabetes duration 22 ± 7.3 years, and early pregnancy HbA1c 52 ± 6.8 mmol/mol [6.9 ± 0.9%]) completed 24 weeks of postpartum follow-up. In the randomized phase, percent time in range 70-180 mg/dL (3.9-10 mmol/L) did not differ between groups (79.2 ± 8.7% vs. 78.2 ± 6.0%; P = 0.41). Participants randomized to closed-loop insulin delivery spent less time <70 mg/dL (3.9 mmol/L) and <54 mg/dL (3.0 mmol/L) (1.7 ± 0.8% vs. 5.5 ± 3.3% [P < 0.001] and 0.3 ± 0.2% vs. 1.1 ± 0.9% [P = 0.008]). Time >180 mg/dL (10 mmol/L) was not different between groups (18.7 ± 8.8% vs. 15.9 ± 7.7%; P = 0.21). In the continuation phase, those initially randomized to sensor-augmented pump therapy had less time <70 mg/dL after initiation of closed-loop insulin delivery (5.5 ± 3.3% vs. 3.3 ± 2.2%; P = 0.039). The closed-loop group maintained similar glycemic metrics in both study phases. There were no episodes of diabetic ketoacidosis or severe hypoglycemia in the randomized or continuation phase in either group.

CONCLUSIONS

Women randomized to closed-loop insulin delivery postpartum had less hypoglycemia than those randomized to sensor-augmented pump therapy. There were no safety concerns. These findings are reassuring for use of closed-loop insulin delivery postpartum because of its potential to reduce hypoglycemia.

MiniMedTM 780G Advanced Hybrid Closed-Loop System Study in Pregnant Women with Type 1 Diabetes

Background: Evaluate the impact of the MiniMed™ 780G advanced hybrid closed-loop (AHCL) system on the glucose profile of pregnant women with type 1 diabetes (T1D) and maternal-neonatal complications. Methods: From April 2021 to September 2022, pregnant women with T1D treated with the AHCL system were included in an observational multicenter retrospective study. Continuous glucose monitoring parameters were analyzed monthly during pregnancy as well as maternal-neonatal complications. Results: Thirteen pregnant women, including a twin pregnancy (age: 33 ± 3 years, hemoglobin A1c [HbA1c]: 7.3% ± 0.7%, insulin doses: 0.72 ± 0.21 U/kg/day) were analyzed. At delivery, gestational age was 37 ± 2 weeks. During first 2 weeks of pregnancy, time in range (TIR, 63-140 mg/dL) was 46% (34-55) and increased to 54% (51-59) (P < 0.01), 64% (48-68) (P < 0.01), and 66% (60-70) (P < 0.001) during the first, second, and third trimester, respectively. During the night, TIR (63-140 mg/dL) was >70% throughout pregnancy. Time below the range <63 mg/dL increased from 0.5% (0-2) to 1.3% (0.7-2.2), 2% (1.2-3.5) (P < 0.05), and 1.3% (1.31-3) (P < 0.05) during the first, second, and third trimester, respectively. At delivery, insulin doses increased to 0.89 ± 0.35 IU/kg/day (P < 0.01), and HbA1c decreased to 6.4% ± 0.6% (P = 0.005). The reported carbohydrate amount increased from 167 ± 363 g/d during early pregnancy to 243 ± 106 g/d (P < 0.01) at delivery. The birthweight was 3134 ± 711 g, with 5/14 macrosomia and 2/14 neonatal hypoglycemia. Moreover, 5/13 patients had a preeclampsia and 9/13 a cesarean section, including three cases of scarred uterus. The Clinical Trial Registration number is: CE-2022-55. Conclusion: The AHCL system provided good glucose control during pregnancy and recommendation targets were reached during the nocturnal period only. The maternal and neonatal complications remained high.

Placental RNA sequencing implicates IGFBP1 in insulin sensitivity during pregnancy and in gestational diabetes

Reduced insulin sensitivity (or greater insulin resistance) is a hallmark of normal physiology in late pregnancy and also underlies gestational diabetes mellitus (GDM) pathophysiology. We conducted transcriptomic profiling of 434 human placentas and identified a strong positive association between insulin-like growth factor binding protein 1 gene (IGFBP1) expression in the placenta and insulin sensitivity at ~ 26 weeks' gestation. Circulating IGFBP1 protein levels rose over the course of pregnancy and declined postpartum, which together with high placental gene expression levels, suggests a placental source. Higher circulating IGFBP1 levels were strongly associated with greater insulin sensitivity (lesser insulin resistance) at ~ 26 weeks' gestation in the same cohort and two additional pregnancy cohorts. In addition, low circulating IGFBP1 levels in early pregnancy predicted subsequent GDM diagnosis in two cohorts. These results implicate IGFBP1 in the glycemic physiology of pregnancy and suggest a role for placental IGFBP1 deficiency in GDM pathogenesis.

The Benefits Of Continuous Glucose Monitoring In Pregnancy

Previous studies have consistently demonstrated the positive effects of continuous glucose monitoring (CGM) on glycemic outcomes and complications of diabetes in people with type 1 diabetes. Guidelines now consider CGM to be an essential and cost-effective device for managing type 1 diabetes. As a result, insurance coverage for it is available. Evidence supporting CGM continues to grow and expand to broader populations, such as pregnant people with type 1 diabetes, people with type 2 diabetes treated only with basal insulin therapy, and even type 2 diabetes that does not require insulin treatment. However, despite the significant risk of hyperglycemia in pregnancy, which leads to complications in more than half of affected newborns, CGM indications and insurance coverage for those patients are unresolved. In this review article, we discuss the latest evidence for using CGM to offer glycemic control and reduce perinatal complications, along with its cost-effectiveness in pregestational type 1 and type 2 diabetes and gestational diabetes mellitus. In addition, we discuss future prospects for CGM coverage and indications based on this evidence.

Women with type 1 diabetes gain more weight during pregnancy compared to age-matched healthy women despite a healthier diet: a prospective case-control observational study

PURPOSE

Women with type 1 diabetes mellitus (T1D), especially those with suboptimal glucose control, have 3-4 greater chances of having babies with birth defects compared to healthy women. We aimed to evaluate glucose control and insulin regimen modifications during the pregnancy of women with T1D, comparing the offspring's weight and the mother's weight change and diet with those of non-diabetic, normal-weight pregnant women.

METHODS

Women with T1D and age-matched healthy women controls (CTR) were consecutively enrolled among pregnant women with normal weight visiting our center. All patients underwent physical examination and diabetes and nutritional counseling, and completed lifestyle and food intake questionnaires.

RESULTS

A total of 44 women with T1D and 34 healthy controls were enrolled. Women with T1D increased their insulin regimen during pregnancy, going from baseline 0.9 ± 0.3 IU/kg to 1.1 ± 0.4 IU/kg (p = 0.009), with a concomitant significant reduction in HbA1c (p = 0.009). Over 50% of T1D women were on a diet compared to < 20% of healthy women (p < 0.001). Women with T1D reported higher consumption of complex carbohydrates, milk, dairy foods, eggs, fruits, and vegetables, while 20% of healthy women never or rarely consumed them. Despite a better diet, women with T1D gained more weight (p = 0.044) and gave birth to babies with higher mean birth weight (p = 0.043), likely due to the daily increase in insulin regimen.

CONCLUSION

A balance between achieving metabolic control and avoiding weight gain is crucial in the management of pregnant women with T1D, who should be encouraged to further improve lifestyle and eating habits with the aim of limiting upward insulin titration adjustments to a minimum.

Management of type 1 diabetes in pregnancy: update on lifestyle, pharmacological treatment, and novel technologies for achieving glycaemic targets

Glucose concentrations within target, appropriate gestational weight gain, adequate lifestyle, and, if necessary, antihypertensive treatment and low-dose aspirin reduces the risk of pre-eclampsia, preterm delivery, and other adverse pregnancy and neonatal outcomes in pregnancies complicated by type 1 diabetes. Despite the increasing use of diabetes technology (ie, continuous glucose monitoring and insulin pumps), the target of more than 70% time in range in pregnancy (TIRp 3·5-7·8 mmol/L) is often reached only in the final weeks of pregnancy, which is too late for beneficial effects on pregnancy outcomes. Hybrid closed-loop (HCL) insulin delivery systems are emerging as promising treatment options in pregnancy. In this Review, we discuss the latest evidence on pre-pregnancy care, management of diabetes-related complications, lifestyle recommendations, gestational weight gain, antihypertensive treatment, aspirin prophylaxis, and the use of novel technologies for achieving and maintaining glycaemic targets during pregnancy in women with type 1 diabetes. In addition, the importance of effective clinical and psychosocial support for pregnant women with type 1 diabetes is also highlighted. We also discuss the contemporary studies examining HCL systems in type 1 diabetes during pregnancies.

Healthcare professionals' views about how pregnant women can benefit from using a closed-loop system: Qualitative study

BACKGROUND

Interest is growing in how closed-loop systems can support attainment of within-target glucose levels amongst pregnant women with type 1 diabetes. We explored healthcare professionals' views about how, and why, pregnant women benefitted from using the CamAPS FX system during the AiDAPT trial.

METHODS

We interviewed 19 healthcare professionals who supported women using closed-loop during the trial. Our analysis focused on identifying descriptive and analytical themes relevant to clinical practice.

RESULTS

Healthcare professionals highlighted clinical and quality-of-life benefits to using closed-loop in pregnancy; albeit, they attributed some of these to the continuous glucose monitoring component. They emphasised that the closed-loop was not a panacea and that, to gain maximum benefit, an effective collaboration between themselves, the woman and the closed-loop was needed. Optimal performance of the technology, as they further noted, also required women to interact with the system sufficiently, but not excessively; a requirement that they felt some women had found challenging. Even where healthcare professionals felt that this balance was not achieved, they suggested that women had still benefitted from using the system. Healthcare professionals reported difficulties predicting how specific women would engage with the technology. In light of their trial experiences, healthcare professionals favoured an inclusive approach to closed-loop rollout in routine clinical care.

CONCLUSIONS

Healthcare professionals recommended that closed-loop systems be offered to all pregnant women with type 1 diabetes in the future. Presenting closed-loop systems to pregnant women and healthcare teams as one pillar of a three-party collaboration may help promote optimal use.

Existing standardised questionnaires do not adequately capture quality-of-life outcomes of greatest importance for those living with type 1 diabetes in pregnancy

BACKGROUND

No standardised questionnaires have been specifically developed to assess the considerable demands of managing type 1 diabetes (T1D) during pregnancy.

AIMS

This study aimed to explore what domains of measurement are important to quality of life during pregnancy with TID and to assess if standardised questionnaires, used by previous researchers, adequately capture patients' reported experience of TID in pregnancy.

METHODS

A qualitative inquiry was conducted using semi-structured focus groups with Canadian women who have experienced T1D in pregnancy. Participants were asked open-ended questions about experiences managing T1D during pregnancy and whether options on standardised tools captured their pregnancy experiences. Audio from focus groups was transcribed verbatim. Two researchers independently analysed the transcripts using inductive thematic analysis. Salient ideas, experiences and key words were coded iteratively and grouped into broader themes and subsequently reviewed by five participants.

RESULTS

The sample included nine participants. Emergent themes included changes in day-to-day routines to manage T1D in pregnancy, fear of hyperglycaemia during pregnancy and of hypoglycaemia postpartum. Participants felt that existing options on standardised questionnaires did not adequately quantify diabetes interference in work, family time, planned activities and sleep, and did not address hyperglycaemia fear.

CONCLUSIONS

Existing standardised questionnaires do not adequately capture patient-reported outcomes of greatest importance for those living with T1D in pregnancy. Future research assessing the impact of therapies on quality-of-life measures in TID pregnancies should quantify their influence on day-to-day activities, adjust measures of sleep quality and capture fear of hyperglycaemia in pregnancy and hypoglycaemia postpartum.

Continuous glucose monitoring: A cost-effective tool to reduce pre-term birth rates in women with type one diabetes

BACKGROUND

Women with type one diabetes experience poorer obstetric outcomes than normoglycaemic women in pregnancy.

OBJECTIVE

To investigate the cost and clinical effectiveness of continuous glucose monitoring (GCM) compared to self-monitoring of blood glucose in improving obstetric outcomes in women with type one diabetes during pregnancy.

MATERIALS AND METHODS

This retrospective cohort study included women with type one diabetes referred to a state-wide tertiary obstetric centre before and after the introduction of government-funded CGMs in Australia in March 2019. Forty-nine women using CGMs were propensity matched on a range of clinical features with a historical group of 49 women with type one diabetes who exclusively used intermittent self-monitoring of blood in the year prior to the introduction of funding of sensors. Medical records and administrative cost data were audited to quantify cost and clinical effectiveness.

RESULTS

There were significantly lower pre-term (95% CI 0.39-0.922; P = 0.026) and very pre-term birth rates (95% CI 1.002-1.184; P = 0.041) in the CGM group. There was a significant reduction in the length of antenatal inpatient hospital stay (P < 0.01) and adult special care unit stay (P = 0.013) and neonatal admission to the neonatal intensive care unit (P = 0.0262) in the continuous glucose monitoring group. CGMs represented a net cost saving to the health care sector of $12 063 per pregnancy where the device was used, with an incremental cost-effectiveness ratio of $3275 per prevented pre-term birth.

CONCLUSIONS

CGM use in pregnancy is a cost-effective intervention for reducing the risk of pre-term birth in women with type one diabetes, resulting in a net cost benefit to the health sector.

Real-world use of Control-IQ™ technology automated insulin delivery in pregnancy: A case series with qualitative interviews

BACKGROUND

Most commercially available automated insulin delivery (AID) systems are not approved for pregnancy use. Information regarding use of the Tandem t:slim X2 insulin pump with Control-IQ™ technology in pregnancy is lacking.

AIMS

This case series aimed to explore glycaemic and qualitative experiences of four early adopters of Control-IQ technology in pregnancy.

METHODS

Participants used Control-IQ technology in pregnancy and postpartum and consented to analysis of glycaemic data and semi-structured interviews.

RESULTS

Case 1 began Control-IQ technology at 10 weeks gestation. Her pregnancy glucose time-in-range (3.5-7.8 mmol/L [63-140 mg/dL]) increased from 58.7% to 73.3% by third trimester. Cases 2-4 began using Control-IQ technology 0-2 months preconception. Pregnancy time-in-range glucose increased from 73.4% to 78.7%, 78% to 83.6%, and 46.5% to 71.9% between first and third trimesters, respectively. A mid-pregnancy decline in time-in-range glucose was observed in two of the four participants related to suboptimal pump setting adjustments and delays in sensor and infusion set replacement. No diabetic ketoacidosis or severe hypoglycaemia occurred. All participants reported reduced diabetes management burden and improved sleep with Control-IQ technology use.

CONCLUSIONS

Early adopters of Control-IQ technology safely used this system off-label in pregnancy and reported reduced diabetes management burden and improved sleep. The largest glycaemic improvements were observed among those with the lowest pregnancy time-in-range glucose at the beginning of pregnancy. Participants with low pregnancy glucose time-in-range increased their time-in-range with Control-IQ technology use and participants with high pregnancy glucose time-in-range maintained and increased their time-in-range with less diabetes management burden.

Closed-loop insulin delivery in pregnant women with type 1 diabetes (CRISTAL): a multicentre randomized controlled trial - study protocol

BACKGROUND

Despite increasing use of continuous glucose monitoring (CGM) and continuous subcutaneous insulin infusion (CSII, insulin pumps) in type 1 diabetes (T1D) in pregnancy, achieving recommended pregnancy glycaemic targets (3.5-7.8 mmol/L or 63-140 mg/dL) remains challenging. Consequently, the risk of adverse pregnancy outcomes remains high. Outside pregnancy, hybrid closed-loop (HCL) insulin delivery systems have led to a paradigm shift in the management of T1D, with 12% higher time in glucose target range (TIR) compared to conventional CSII. However, most commercially available HCL systems are currently not approved for use in pregnancy. This study aims to evaluate the efficacy, safety and cost-effectiveness of the MiniMed™ 780G HCL system (Medtronic) in T1D in pregnancy.

METHODS

In this international, open-label, randomized controlled trial (RCT), we will compare the MiniMed™ 780G HCL system to standard of care (SoC) in T1D in pregnancy. Women aged 18-45 years with T1D diagnosis of at least one year, HbA1c ≤ 86 mmol/mol (≤ 10%), and confirmed singleton pregnancy up to 11 weeks 6 days will be eligible. After providing written informed consent, all participants will wear a similar CGM system (Guardian™ 3 or Guardian™ 4 CGM) during a 10-day run-in phase. After the run-in phase, participants will be randomised 1:1 to 780G HCL (intervention) or SoC [control, continuation of current T1D treatment with multiple daily injections (MDI) or CSII and any type of CGM] stratified according to centre, baseline HbA1c (< 53 vs. ≥ 53 mmol/mol or < 7 vs. ≥ 7%), and method of insulin delivery (MDI or CSII). The primary outcome will be the time spent within the pregnancy glucose target range, as measured by the CGM at four time points in pregnancy: 14-17, 20-23, 26-29, and 33-36 weeks. Prespecified secondary outcomes will be overnight TIR, time below range (TBR: <3.5 mmol/L or < 63 mg/dL), and overnight TBR. Other outcomes will be exploratory. The planned sample size is 92 participants. The study will end after postpartum discharge from hospital. Analyses will be performed according to intention-to-treat as well as per protocol.

DISCUSSION

This large RCT will evaluate a widely used commercially available HCL system in T1D in pregnancy. Recruitment began in January 2021 and was completed in October 2022. Study completion is expected in May 2023.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04520971. Registration date: August 20, 2020. https://clinicaltrials.gov/ct2/show/NCT04520971.

First-Trimester Maternal Serum Adiponectin/Leptin Ratio in Pre-Eclampsia and Fetal Growth

The serum adiponectin/leptin ratio (A/L ratio) is a surrogate marker of insulin sensitivity. Pre-eclampsia (PE) is associated with maternal metabolic syndrome and occasionally impaired fetal growth. We assessed whether the A/L ratio in first-trimester maternal serum was associated with PE and/or birth weight. Adiponectin and leptin were quantitated in first-trimester blood samples (gestational week 10+3−13+6) from 126 women who later developed PE with proteinuria (98 mild PE; 21 severe PE; 7 HELLP syndrome), and 297 controls, recruited from the Copenhagen First-Trimester Screening Study. The A/L ratio was reduced in PE pregnancies, median 0.17 (IQR: 0.12−0.27) compared with controls, median 0.32 (IQR: 0.19−0.62) (p < 0.001). A multiple logistic regression showed that PE was negatively associated with log A/L ratio independent of maternal BMI (odds ratio = 0.315, 95% CI = 0.191 to 0.519). Adiponectin (AUC = 0.632) and PAPP-A (AUC = 0.605) were negatively associated with PE, and leptin (AUC = 0.712) was positively associated with PE. However, the A/L ratio was a better predictor of PE (AUC = 0.737), albeit not clinically relevant as a single marker. No significant association was found between A/L ratio and clinical severity of pre-eclampsia or preterm birth. PE was associated with a significantly lower relative birth weight (p < 0.001). A significant negative correlation was found between relative birth weight and A/L ratio in controls (β = −0.165, p < 0.05) but not in PE pregnancies), independent of maternal BMI. After correction for maternal BMI, leptin was significantly associated with relative birth weight (β = 2.98, p < 0.05), while adiponectin was not significantly associated. Our findings suggest that an impairment of the A/L ratio (as seen in metabolic syndrome) in the first trimester is characteristic of PE, while aberrant fetal growth in PE is not dependent on insulin sensitivity, but rather on leptin-associated pathways.

15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2023

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

What's new in the management of type 1 diabetes in pregnancy?

Type 1 diabetes in pregnancy is associated with an increased risk of complications for both mother and fetus. However, managing glycaemia during pregnancy to reduce these risks is challenging, owing to changes in insulin resistance with advancing gestation, as well as increased daily variation in insulin pharmacokinetics. These factors can add significant psychological and daily self-care burden to mothers during what may already be an anxious time. Increasingly, diabetes technologies are being used during pregnancy to improve and facilitate diabetes self-care. While these can be empowering for people with type 1 diabetes, careful consideration is required in relation to how and when these can be continued safely in the inpatient setting (including acute antenatal admissions, labour and delivery) and when extra support is required from adequately trained healthcare professionals. This article describes current forms of diabetes technologies used and the latest national guidance relating to the care of type 1 diabetes in pregnancy.

Carbohydrate Intake and Closed-Loop Insulin Delivery System during Two Subsequent Pregnancies in Type 1 Diabetes

Carbohydrate intake is one of the main determinants of glycemic control. In pregnancy, achievement of tight glycemic control is of utmost importance; however, data on the role of hybrid closed-loop systems (HCLs) in pregnancy are scarce. Therefore, we aimed to assess glycemic control achieved through the use of HCLs, and its association with carbohydrate intake in type 1 diabetes pregnancy. We included data from women with a sensor-augmented pump (SAP) during their first pregnancy and HCL use during the subsequent pregnancy. Student's paired t-test was used to compare data between both pregnancies. Six women were identified, with age 30.2 ± 3.6 vs. 33.0 ± 3.6 years, diabetes duration 23 ± 5 vs. 26 ± 5 years, and baseline HbA1c 6.7 ± 0.7% (50.1 ± 7.7 mmol/mol) vs. 6.3 ± 0.6% (45.2 ± 6.5 mmol/moll) in the first and second pregnancies, respectively. Time with glucose in the range 3.5-7.8 mmol/L was 69.1 ± 6.7 vs. 78.6 ± 7.4%, p = 0.045, with the HCLs compared to SAP. Higher meal frequency, but not the amount of carbohydrate consumption, was associated with more time spent in the target range and lower glycemic variability. HCLs and meal frequency were associated with better glycemic control in a small series of pregnant women with type 1 diabetes. Whether this translates to better perinatal outcomes remains to be seen.

Flash glucose monitoring system in special situations

The management of diabetes mellitus (DM) requires maintaining glycemic control, and patients must keep their blood glucose levels close to the normal range to reduce the risk of microvascular complications and cardiovascular events. While glycated hemoglobin (A1C) is currently the primary measure for glucose management and a key marker for long-term complications, it does not provide information on acute glycemic excursions and overall glycemic variability. These limitations may even be higher in some special situations, thereby compromising A1C accuracy, especially when wider glycemic variability is expected and/or when the glycemic goal is more stringent. To attain adequate glycemic control, continuous glucose monitoring (CGM) is more useful than self-monitoring of blood glucose (SMBG), as it is more convenient and provides a greater amount of data. Flash Glucose Monitoring (isCGM /FGM) is a widely accepted option of CGM for measuring interstitial glucose levels in individuals with DM. However, its application under special conditions, such as pregnancy, patients on hemodialysis, patients with cirrhosis, during hospitalization in the intensive care unit and during physical exercise has not yet been fully validated. This review addresses some of these specific situations in which hypoglycemia should be avoided, or in pregnancy, where strict glycemic control is essential, and the application of isCGM/FGM could alleviate the shortcomings associated with poor glucose control or high glycemic variability, thereby contributing to high-quality care.

Intermittently scanned continuous glucose monitoring is associated with lower spontaneous abortion rate compared with conventional blood glucose monitoring in pregnant women with type 1 diabetes: An observational study

AIM

The objective of the present real-life study in France was to assess and compare characteristics and outcomes in a cohort of pregnant women with type 1 diabetes (T1D) using intermittently scanned continuous glucose monitoring (isCGM) or conventional blood glucose monitoring (BGM).

MATERIAL AND METHODS

We performed an observational study of a cohort of 153 women with T1D: 77 women were using isCGM, and 76 were using BGM. We compared the groups' maternal characteristics and maternal-fetal complications. The level of HbA1c was measured before pregnancy and then four times (after 8-12, 24-28, 30-33, and 35-37 weeks of gestation).

RESULTS

The two groups were similar in terms of age, prepregnancy BMI, diabetes duration, and diabetic vascular complications. There were no significant intergroup differences in the obstetric history. The spontaneous abortion rate was lower in the isCGM group than in the blood glucose monitoring group (5.3% vs. 20%, respectively; p = .0129), while the prepregnancy and first-trimester HbA1c levels were similar. There were no significant intergroup differences in the incidence of other maternal-fetal complications.

CONCLUSIONS

This observational study demonstrates that isCGM use is associated with lower spontaneous abortion compared with conventional BGM. Large prospective studies are needed to corroborate our findings and fully understand the relationship between glucose data at the time of conception/early pregnancy and foetal outcome.

Addition of intermittently scanned continuous glucose monitoring to standard care in a cohort of pregnant women with type 1 diabetes: effect on glycaemic control and pregnancy outcomes

AIMS/HYPOTHESIS

The aim of this study was to assess whether the addition of intermittently scanned continuous glucose monitoring (isCGM) to standard care (self-monitoring of blood glucose [SMBG] alone) improves glycaemic control and pregnancy outcomes in women with type 1 diabetes and multiple daily injections.

METHODS

This was a multicentre observational cohort study of 300 pregnant women with type 1 diabetes in Spain, including 168 women using SMBG (standard care) and 132 women using isCGM in addition to standard care. In addition to HbA1c, the time in range (TIR), time below range (TBR) and time above range (TAR) with regard to the pregnancy glucose target range (3.5-7.8 mmol/l) were also evaluated in women using isCGM. Logistic regression models were performed for adverse pregnancy outcomes adjusted for baseline maternal characteristics and centre.

RESULTS

The isCGM group had a lower median HbA1c in the second trimester than the SMBG group (41.0 [IQR 35.5-46.4] vs 43.2 [IQR 37.7-47.5] mmol/mol, 5.9% [IQR 5.4-6.4%] vs 6.1% [IQR 5.6-6.5%]; p=0.034), with no differences between the groups in the other trimesters (SMBG vs isCGM: first trimester 47.5 [IQR 42.1-54.1] vs 45.9 [IQR 39.9-51.9] mmol/mol, 6.5% [IQR 6.0-7.1%] vs 6.4% [IQR 5.8-6.9%]; third trimester 43.2 [IQR 39.9-47.5] vs 43.2 [IQR 39.9-47.5] mmol/mol, 6.1% [IQR 5.8-6.5%] vs 6.1% [IQR 5.7-6.5%]). The whole cohort showed a slight increase in HbA1c from the second to the third trimester, with a significantly higher rise in the isCGM group than in the SMBG group (median difference 2.2 vs 1.1 mmol/mol [0.2% vs 0.1%]; p=0.033). Regarding neonatal outcomes, newborns of women using isCGM were more likely to have neonatal hypoglycaemia than newborns of non-sensor users (27.4% vs 19.1%; ORadjusted 2.20 [95% CI 1.14, 4.30]), whereas there were no differences between the groups in large-for-gestational-age (LGA) infants (40.6% vs 45.1%; ORadjusted 0.73 [95% CI 0.42, 1.25]), Caesarean section (57.6% vs 48.8%; ORadjusted 1.33 [95% CI 0.78, 2.27]) or prematurity (27.3% vs 24.8%; ORadjusted 1.05 [95% CI 0.55, 1.99]) in the adjusted models. A sensitivity analysis in pregnancies without LGA infants or prematurity also showed that the use of isCGM was associated with a higher risk of neonatal hypoglycaemia (non-LGA: ORadjusted 2.63 [95% CI 1.01, 6.91]; non-prematurity: ORadjusted 2.52 [95% CI 1.12, 5.67]). For isCGM users, the risk of delivering an LGA infant was associated with TIR, TAR and TBR in the second trimester in the logistic regression analysis.

CONCLUSIONS/INTERPRETATION

isCGM use provided an initial improvement in glycaemic control that was not sustained. Furthermore, offspring of isCGM users were more likely to have neonatal hypoglycaemia, with similar rates of macrosomia and prematurity to those of women receiving standard care.

Hypoglycemia in Prospective Multicenter Study of Pregnancies with Pre-Existing Type 1 Diabetes on Sensor-Augmented Pump Therapy: The LOIS-P Study

Background: Pregnancies in type 1 diabetes are high risk, and data in the United States are limited regarding continuous glucose monitoring (CGM)-based hypoglycemia throughout pregnancy while on sensor-augmented insulin pump therapy. Materials and Methods: Pregnant women with type 1 diabetes in the LOIS-P Study (Longitudinal Observation of Insulin use and glucose Sensor metrics in Pregnant women with type 1 diabetes using continuous glucose monitors and insulin pumps) were enrolled before 17 weeks gestation at three U.S. centers and we used their personal insulin pump and a study Dexcom G6 CGM. We analyzed data of 25 pregnant women for CGM hypoglycemia based on international consensus guidelines for percentage time <63 and 54 mg/dL, hypoglycemic events and prolonged hypoglycemia events for 24-h, daytime, and overnight periods, and severe hypoglycemia (SH) episodes. Results: For a 24-h period, biweekly median percentage of time <63 mg/dL ranged from 0.8% at biweek 4-5 to 3.7% at biweek 14-15 with high variability throughout pregnancy. Median percentage of time <63 and 54 mg/dL was higher overnight than daytime (P < 0.01). Hypoglycemic events occurred throughout the pregnancy, ranged 1-4 events per 2 weeks, significantly decreased after the 20th week, and occurred predominantly during daytime (P < 0.01). For overnight period, hypoglycemia and events were more concentrated from 12 to 3 am. Seven prolonged hypoglycemia events without any associated SH occurred in four participants (16%), primarily overnight. Three participants experienced a single episode of SH. Conclusions: Our results suggest a higher overall risk of hypoglycemia throughout pregnancy during the overnight period with continued daytime risk of hypoglycemic events in pregnancies complicated by type 1 diabetes.

Continuous Glucose Monitoring Metrics and Birth Weight: Informing Management of Type 1 Diabetes Throughout Pregnancy

OBJECTIVE

To determine gestational weekly changes in continuous glucose monitoring (CGM) metrics and 24-h glucose profiles and their relationship to infant birth weight in pregnant women with type 1 diabetes.

RESEARCH DESIGN AND METHODS

An analysis of >10.5 million CGM glucose measures from 386 pregnant women with type 1 diabetes from two international multicenter studies was performed. CGM glucose metrics and 24-h glucose profiles were calculated for each gestational week, and the relationship to normal (10-90th percentile) and large (>90th percentile) for gestational age (LGA) birth weight infants was determined.

RESULTS

Mean CGM glucose concentration fell and percentage of time spent in the pregnancy target range of 3.5-7.8 mmol/L (63-140 mg/dL) increased in the first 10 weeks of pregnancy and plateaued until 28 weeks of gestation, before further improvement in mean glucose and percentage of time in range until delivery. Maternal CGM glucose metrics diverged at 10 weeks of gestation, with significantly lower mean CGM glucose concentration (7.1 mmol/L; 95% CI 7.05-7.15 [127.8 mg/dL; 95% CI 126.9-128.7] vs. 7.5 mmol/L; 95% CI 7.45-7.55 [135 mg/dL; 95% CI 134.1-135.9]) and higher percentage of time in range (55%; 95% CI 54-56 vs. 50%; 95% CI 49-51) in women who had normal versus LGA. The 24-h glucose profiles were significantly higher across the day from 10 weeks of gestation in LGA.

CONCLUSIONS

Normal birth weight is associated with achieving significantly lower mean CGM glucose concentration across the 24-h day and higher CGM time in range from before the end of the first trimester, emphasizing the need for a shift in clinical management, with increased focus on using weekly CGM glucose targets for optimizing maternal glycemia from early pregnancy.

Type 1 diabetes and pregnancy: An update on glucose monitoring and insulin treatment

The relevance of type 1 diabetes during pregnancy stems from its impact on the health of mother and offspring and its increasing prevalence. Glycemic control during pregnancy is one of the main risk factors for adverse events. Besides, treatment becomes a major challenge not only due to the modifications in insulin requirements due to changes in hormones and cytokines but also to the stricter control targets. Given the recent appearance of new ultra-rapid and basal insulin analogues and the constant evolution of technology to treat people with diabetes, we review these aspects in relation to the treatment of women with type 1 diabetes during pregnancy.

Falling Insulin Requirement in Pregnant Women With Diabetes Delivering Preterm: Prevalence, Predictors, and Consequences

CONTEXT

Falling insulin requirements often lead to considerations of whether a pregnancy can continue safely or if delivery is indicated.

OBJECTIVE

To evaluate prevalence and predictors of falling insulin requirements in pregnant women with preexisting diabetes delivering preterm and to explore the relationship to fetal asphyxia and neonatal morbidity.

METHODS

A prospective cohort study of 101 consecutive singleton pregnant women with preexisting diabetes delivering preterm < 37 weeks (68 type 1 and 33 type 2 diabetes) where the prevalence of falling insulin requirements (≥20%) before delivery was recorded.

RESULTS

In total, 27% (27/101) experienced falling insulin requirements of median 30% (interquartile range 24-40) before delivery. In all women with type 1 diabetes, the prevalence was 37% (25/68), whereas it was 43% (24/56) in those with indicated preterm delivery and 6% (2/33) among women with type 2 diabetes. In women with type 1 diabetes and indicated preterm delivery, falling insulin requirements were first identified at 34 + 5 (33 + 6-35 + 4) weeks + days and delivery occurred 3 (1-9) days later. Gestational age at delivery, prevalence of suspected fetal asphyxia, and neonatal morbidity were similar in women with and without falling insulin requirements. Neither glycemic control, nausea, or preeclampsia was associated with falling insulin requirement.

CONCLUSION

Falling insulin requirements often preceded preterm delivery in women with type 1 diabetes, foremost when preterm delivery was indicated, but was not related to fetal asphyxia or neonatal morbidity. Whether falling insulin requirements in late pregnancy are a warning sign of placental insufficiency or mainly reflects variations in normal physiology needs further investigation.

A new mathematical mixed effect model was used for analysing the influencing factors of hypoglycaemia of newborns from women with gestational diabetes mellitus

A mathematical mixed effect model was established to analyse the factors of neonatal hypoglycaemia of gestational diabetes mellitus (GDM). 229 cases of GDM patients were enrolled in this study. The data were analysed by logarithmic transformation of non-normal distribution. Furthermore, the mathematical model was used to analyse influencing factors of hypoglycaemia of neonatal from women with GDM. The results showed that the blood glucose distribution level had a trend of increasing with time, which indicates that it is necessary to strengthen blood glucose intervention of newborns from GDM maternal and provides a data for the timely detection of hypoglycaemia in GDM newborns. Furthermore, we successfully established the GDM newborn blood glucose level mixed mathematical model. From this model, we calculated the GDM newborn blood glucose normal confidence interval based on mixed factors. The results indicate that the minimum value of blood glucose level in GDM newborns did not exceed the risk level 2.2 mmol/L. We concluded that the mathematical mixed effect model is successfully established, from which the change discipline of blood glucose level of newborn from GDM parturient are found. Impact statementWhat is already known on this subject? The morbidity of gestational diabetes mellitus (GDM) in China has been increased. However, the clinical data is difficult to be collected and the data that is used for statistics is not enough, which makes it difficult to understand the neonatal hypoglycaemia of GDM more clearly.What do the results of this study add? In this study, we successfully established a mathematical mixed effect model of neonatal hypoglycaemia of women with GDM, which can investigate the influence factor of hypoglycaemia of newborn from women with GDM to find the discipline of blood glucose level of newborn from GDM parturient via mathematical model.What are the implications of these findings for clinical practice and/or further research? Our research helps to better understand and improve the health problem of pregnant women with GDM and their newborn babies.

Time in range measurements for hyperglycemia management during pregnancy

The prevalence of adverse pregnancy outcomes associated with poor glycemic control are increasing. Accordingly, effective blood glucose monitoring during pregnancy has become a subject of intense interest. Continuous glucose monitoring (CGM) displays dynamic changes in blood glucose by using probes to measure glucose concentration in the interstitial fluid, and the rapid development of CGM has enabled the investigation of time in range (TIR) in the glucose target range as a new parameter to evaluate blood glucose. International guidelines have identified TIR as an important blood glucose assessment method for pregnant patients with type 1 diabetes mellitus that overcomes the limitations of conventional gestational blood glucose monitoring, better reflects fluctuation in blood glucose during pregnancy, and effectively improves maternal and neonatal outcomes. However, there is little clinical evidence for the use of TIR in pregnant women with gestational diabetes mellitus and those with pre-pregnant type 2 diabetes mellitus. TIR is expected to become a critical indicator of blood glucose control and management in hyperglycemic pregnant patients. We review the research progress of TIR to help clinicians understand the field of blood glucose monitoring in pregnant women with hyperglycemia.

Zone-MPC Automated Insulin Delivery Algorithm Tuned for Pregnancy Complicated by Type 1 Diabetes

Type 1 diabetes (T1D) increases the risk for pregnancy complications. Increased time in the pregnancy glucose target range (63-140 mg/dL as suggested by clinical guidelines) is associated with improved pregnancy outcomes that underscores the need for tight glycemic control. While closed-loop control is highly effective in regulating blood glucose levels in individuals with T1D, its use during pregnancy requires adjustments to meet the tight glycemic control and changing insulin requirements with advancing gestation. In this paper, we tailor a zone model predictive controller (zone-MPC), an optimization-based control strategy that uses model predictions, for use during pregnancy and verify its robustness in-silico through a broad range of scenarios. We customize the existing zone-MPC to satisfy pregnancy-specific glucose control objectives by having (i) lower target glycemic zones (i.e., 80-110 mg/dL daytime and 80-100 mg/dL overnight), (ii) more assertive correction bolus for hyperglycemia, and (iii) a control strategy that results in more aggressive postprandial insulin delivery to keep glucose within the target zone. The emphasis is on leveraging the flexible design of zone-MPC to obtain a controller that satisfies glycemic outcomes recommended for pregnancy based on clinical insight. To verify this pregnancy-specific zone-MPC design, we use the UVA/Padova simulator and conduct in-silico experiments on 10 subjects over 13 scenarios ranging from scenarios with ideal metabolic and treatment parameters for pregnancy to extreme scenarios with such parameters that are highly deviant from the ideal. All scenarios had three meals per day and each meal had 40 grams of carbohydrates. Across 13 scenarios, pregnancy-specific zone-MPC led to a 10.3 ± 5.3% increase in the time in pregnancy target range (baseline zone-MPC: 70.6 ± 15.0%, pregnancy-specific zone-MPC: 80.8 ± 11.3%, p < 0.001) and a 10.7 ± 4.8% reduction in the time above the target range (baseline zone-MPC: 29.0 ± 15.4%, pregnancy-specific zone-MPC: 18.3 ± 12.0, p < 0.001). There was no significant difference in the time below range between the controllers (baseline zone-MPC: 0.5 ± 1.2%, pregnancy-specific zone-MPC: 3.5 ± 1.9%, p = 0.1). The extensive simulation results show improved performance in the pregnancy target range with pregnancy-specific zone MPC, suggest robustness of the zone-MPC in tight glucose control scenarios, and emphasize the need for customized glucose control systems for pregnancy.

Glycemic Control and Aspirin Resistance in Patients Taking Low-Dose Aspirin for Pre-eclampsia Prevention

OBJECTIVES

To assess the association between aspirin and glycemic control in diabetic, pregnant patients, and the risk for aspirin resistance in those with poor glycemic control across gestation taking low-dose aspirin (LDA) for pre-eclampsia (PEC) prevention.

STUDY DESIGN

We performed a secondary analysis of samples collected during the Maternal-Fetal Medicine Units trial of LDA for PEC prevention. A subset of insulin-controlled diabetic patient samples on placebo or 60 mg aspirin daily were evaluated. Glycosylated hemoglobin was measured at randomization, mid-second trimester, and third trimester time points. Thromboxane B₂ (TXB₂) measurements were previously assessed as part of the original study. Primary outcome was the effect of LDA on glycosylated hemoglobin levels compared with placebo across gestation.

RESULTS

Levels of glycosylated hemoglobin increased across gestation in the placebo group (2,067.7 [interquartile range, IQR: 1,624.6-2,713.5 µg/mL] vs. 2,461.9 [1,767.0-3,209.9 µg/mL] vs. 3,244.3 [2,691.5-4,187.0 µg/mL]; p < 0.01) compared with no difference in levels of glycosylated hemoglobin across gestation in the LDA group (2,186.4 [IQR: 1,462.3-3,097.7 µg/mL] vs. 2,337.1 [1,327.7-5,932.6 µg/mL] vs. 2,532.9 [1,804.9-5,511.8 µg/mL]; p = 0.78). Higher levels of glycosylated hemoglobin were associated with increased TXB₂ levels prior to randomization (r = 0.67, p < 0.05). Incomplete TXB₂ was higher in pregnancies with increasing levels of glycosylated hemoglobin compared with those with decreasing levels of glycosylated hemoglobin across gestation (69.2 vs. 18.1%, p = 0.02).

CONCLUSION

LDA exposure may be beneficial to glycemic control in this patient population. Additionally, poor glycemic control is associated with a higher level of TXB₂ in diabetic pregnant patients on LDA. Higher doses of aspirin may be required in these patients to prevent development of PEC.

KEY POINTS

· Low-dose aspirin may improve glycemic control.. · Poor glycemic control increases risk for aspirin resistance.. · Higher doses of aspirin may be required for pre-eclampsia prevention..

15. Management of Diabetes in Pregnancy: Standards of Medical Care in Diabetes-2022

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc22-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc22-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.