SummaryBackgroundPregnant women with type 1 diabetes are a high-risk population who are recommended to strive for optimal glucose control, but neonatal outcomes attributed to maternal hyperglycaemia remain suboptimal. Our aim was to examine the effectiveness of continuous glucose monitoring (CGM) on maternal glucose control and obstetric and neonatal health outcomes.MethodsIn this multicentre, open-label, randomised controlled trial, we recruited women aged 18–40 years with type 1 diabetes for a minimum of 12 months who were receiving intensive insulin therapy. Participants were pregnant (≤13 weeks and 6 days' gestation) or planning pregnancy from 31 hospitals in Canada, England, Scotland, Spain, Italy, Ireland, and the USA. We ran two trials in parallel for pregnant participants and for participants planning pregnancy. In both trials, participants were randomly assigned to either CGM in addition to capillary glucose monitoring or capillary glucose monitoring alone. Randomisation was stratified by insulin delivery (pump or injections) and baseline glycated haemoglobin (HbA1c). The primary outcome was change in HbA1c from randomisation to 34 weeks' gestation in pregnant women and to 24 weeks or conception in women planning pregnancy, and was assessed in all randomised participants with baseline assessments. Secondary outcomes included obstetric and neonatal health outcomes, assessed with all available data without imputation. This trial is registered with ClinicalTrials.gov, number NCT01788527.FindingsBetween March 25, 2013, and March 22, 2016, we randomly assigned 325 women (215 pregnant, 110 planning pregnancy) to capillary glucose monitoring with CGM (108 pregnant and 53 planning pregnancy) or without (107 pregnant and 57 planning pregnancy). We found a small difference in HbA1c in pregnant women using CGM (mean difference −0·19%; 95% CI −0·34 to −0·03; p=0·0207). Pregnant CGM users spent more time in target (68% vs 61%; p=0·0034) and less time hyperglycaemic (27% vs 32%; p=0·0279) than did pregnant control participants, with comparable severe hypoglycaemia episodes (18 CGM and 21 control) and time spent hypoglycaemic (3% vs 4%; p=0·10). Neonatal health outcomes were significantly improved, with lower incidence of large for gestational age (odds ratio 0·51, 95% CI 0·28 to 0·90; p=0·0210), fewer neonatal intensive care admissions lasting more than 24 h (0·48; 0·26 to 0·86; p=0·0157), fewer incidences of neonatal hypoglycaemia (0·45; 0·22 to 0·89; p=0·0250), and 1-day shorter length of hospital stay (p=0·0091). We found no apparent benefit of CGM in women planning pregnancy. Adverse events occurred in 51 (48%) of CGM participants and 43 (40%) of control participants in the pregnancy trial, and in 12 (27%) of CGM participants and 21 (37%) of control participants in the planning pregnancy trial. Serious adverse events occurred in 13 (6%) participants in the pregnancy trial (eight [7%] CGM, five [5%] control) and in three (3%) participants in the planning pregnancy trial (two [4%] CGM and one [2%] control). The most...

Objective To evaluate the effectiveness of continuous glucose monitoring during pregnancy on maternal glycaemic control, infant birth weight, and risk of macrosomia in women with type 1 and type 2 diabetes.Design Prospective, open label randomised controlled trial.Setting Two secondary care multidisciplinary obstetric clinics for diabetes in the United Kingdom.Participants 71 women with type 1 diabetes (n=46) or type 2 diabetes (n=25) allocated to antenatal care plus continuous glucose monitoring (n=38) or to standard antenatal care (n=33).Intervention Continuous glucose monitoring was used as an educational tool to inform shared decision making and future therapeutic changes at intervals of 4-6 weeks during pregnancy. All other aspects of antenatal care were equal between the groups.Main outcome measures The primary outcome was maternal glycaemic control during the second and third trimesters from measurements of HbA1c levels every four weeks. Secondary outcomes were birth weight and risk of macrosomia using birthweight standard deviation scores and customised birthweight centiles. Statistical analyses were done on an intention to treat basis.Results Women randomised to continuous glucose monitoring had lower mean HbA1c levels from 32 to 36 weeks’ gestation compared with women randomised to standard antenatal care: 5.8% (SD 0.6) v 6.4% (SD 0.7). Compared with infants of mothers in the control arm those of mothers in the intervention arm had decreased mean birthweight standard deviation scores (0.9 v 1.6; effect size 0.7 SD, 95% confidence interval 0.0 to 1.3), decreased median customised birthweight centiles (69% v 93%), and a reduced risk of macrosomia (odds ratio 0.36, 95% confidence interval 0.13 to 0.98).Conclusion Continuous glucose monitoring during pregnancy is associated with improved glycaemic control in the third trimester, lower birth weight, and reduced risk of macrosomia.Trial registration Current Controlled Trials ISRCTN84461581.

BACKGROUNDIn patients with type 1 diabetes who are not pregnant, closed-loop (automated) insulin delivery can provide better glycemic control than sensor-augmented pump therapy, but data are lacking on the efficacy, safety, and feasibility of closed-loop therapy during pregnancy. METHODSWe performed an open-label, randomized, crossover study comparing overnight closed-loop therapy with sensor-augmented pump therapy, followed by a continuation phase in which the closed-loop system was used day and night. Sixteen pregnant women with type 1 diabetes completed 4 weeks of closed-loop pump therapy (intervention) and sensor-augmented pump therapy (control) in random order. During the continuation phase, 14 of the participants used the closed-loop system day and night until delivery. The primary outcome was the percentage of time that overnight glucose levels were within the target range (63 to 140 mg per deciliter [3.5 to 7.8 mmol per liter]). RESULTSThe percentage of time that overnight glucose levels were in the target range was higher during closed-loop therapy than during control therapy (74.7% vs. 59.5%; absolute difference, 15.2 percentage points; 95% confidence interval, 6.1 to 24.2; P = 0.002). The overnight mean glucose level was lower during closed-loop therapy than during control therapy (119 vs. 133 mg per deciliter [6.6 vs. 7.4 mmol per liter], P = 0.009). There were no significant differences between closed-loop and control therapy in the percentage of time in which glucose levels were below the target range (1.3% and 1.9%, respectively; P = 0.28), in insulin doses, or in adverseevent rates. During the continuation phase (up to 14.6 additional weeks, including antenatal hospitalizations, labor, and delivery), glucose levels were in the target range 68.7% of the time; the mean glucose level was 126 mg per deciliter (7.0 mmol per liter). No episodes of severe hypoglycemia requiring third-party assistance occurred during either phase. CONCLUSIONSOvernight closed-loop therapy resulted in better glucose control than sensor-augmented pump therapy in pregnant women with type 1 diabetes. Women receiving day-and-night closed-loop therapy maintained glycemic control during a high proportion of the time in a period that encompassed antenatal hospital admission, labor, and delivery.

OBJECTIVE -The objective of this study was to examine the relationship between prepregnancy care, glycemic control, maternal hypoglycemia, and pregnancy outcomes in women with type 1 diabetes.RESEARCH DESIGN AND METHODS -This was a prospective observational cohort study of women with type 1 diabetes who delivered from 1991 to 2002. Outcome measures were attendance at a clinic for prepregnancy care, maternal HbA 1c (A1C) throughout pregnancy, maternal severe hypoglycemic episodes, macrosomia, preeclampsia, premature delivery (delivery before 37 weeks), very premature delivery (delivery before 34 weeks), spontaneous abortion, and adverse pregnancy outcome (defined as major malformation, stillbirth, and neonatal death).RESULTS -There were 290 pregnancies, in which 110 (38%) women had prepregnancy care. The prepregnancy care group contained more primiparous women (54.7 vs. 40.6%; P ϭ 0.021) and fewer smokers (9.4 vs. 28.7%; P Ͻ 0.0001). They registered earlier (6.6 vs. 8.3 weeks, P Ͻ 0.0001) and had a lower A1C at the initial visit (6.5% vs. 7.6%; P Ͻ 0.0001). Adverse pregnancy outcomes and very premature deliveries were significantly lower in women who received prepregnancy care (2.9 vs. 10.2%; P ϭ 0.03 and 5.0 vs. 14.2%; P ϭ 0.02, respectively). In contrast, between groups, there was no difference in A1C after 24 weeks or in the rates of macrosomia, preeclampsia, or maternal severe hypoglycemic episodes.CONCLUSIONS -Prepregnancy care was associated with improved glycemic control in early pregnancy and significant reductions in adverse pregnancy outcome (malformation, stillbirth, and neonatal death) and very premature delivery. However, prepregnancy care failed to have an impact on glycemic control in later pregnancy or to reduce the risk of macrosomia and preeclampsia. Diabetes Care 29:1744 -1749, 2006D iabetes is the most common medical condition to complicate pregnancy, affecting 1 pregnant woman in 250 in the U.K. (1). Women with type 1 diabetes have a poor outcome compared with women without diabetes, with increased rates of congenital malformations, preeclampsia, premature delivery, perinatal mortality, and risk of delivering a macrosomic baby (2). The Confidential Enquiry into Maternal and Child Health (CEMACH) confirms a nearly fourfold rise in perinatal mortality rates and twofold rise in congenital malformation rate in women with diabetes over baseline rates in England, Wales, and Northern Ireland (1). Studies suggest that the risk of adverse outcome (malformation and perinatal mortality) is related to poor glycemic control in early pregnancy (3,4). The critical time period for optimal glycemic control is before 7 weeks' gestation, during early organogenesis (5). Prepregnancy care is the only intervention that targets glycemic control at this critical early stage and has been associated with improvements in maternal and perinatal outcomes (4,6 -13). The association of prepregnancy care with reduced risk of major congenital malformation has been further confirmed on meta-analysis (14). Some studies of macr...

OBJECTIVETo implement and evaluate a regional prepregnancy care program in women with type 1 and type 2 diabetes.RESEARCH DESIGN AND METHODSPrepregnancy care was promoted among patients and health professionals and delivered across 10 regional maternity units. A prospective cohort study of 680 pregnancies in women with type 1 and type 2 diabetes was performed. Primary outcomes were adverse pregnancy outcome (congenital malformation, stillbirth, or neonatal death), congenital malformation, and indicators of pregnancy preparation (5 mg folic acid, gestational age, and A1C). Comparisons were made with a historical cohort (n = 613 pregnancies) from the same units during 1999–2004.RESULTSA total of 181 (27%) women attended, and 499 women (73%) did not attend prepregnancy care. Women with prepregnancy care presented earlier (6.7 vs. 7.7 weeks; P < 0.001), were more likely to take 5 mg preconception folic acid (88.2 vs. 26.7%; P < 0.0001) and had lower A1C levels (A1C 6.9 vs. 7.6%; P < 0.0001). They had fewer adverse pregnancy outcomes (1.3 vs. 7.8%; P = 0.009). Multivariate logistic regression confirmed that in addition to glycemic control, lack of prepregnancy care was independently associated with adverse outcome (odds ratio 0.2 [95% CI 0.05–0.89]; P = 0.03). Compared with 1999–2004, folic acid supplementation increased (40.7 vs. 32.5%; P = 0.006) and congenital malformations decreased (4.3 vs. 7.3%; P = 0.04).CONCLUSIONSRegional prepregnancy care was associated with improved pregnancy preparation and reduced risk of adverse pregnancy outcome in type 1 and type 2 diabetes. Prepregnancy care had benefits beyond improved glycemic control and was a stronger predictor of pregnancy outcome than maternal obesity, ethnicity, or social disadvantage.