T1D Pregnancy & Me will partner with pregnant participants living with type 1 diabetes (T1D) in the United States to collect real-world data on management of T1D in pregnancy. This is a remote study where participants can complete online surveys and share device data (continuous glucose monitor (CGM) data and insulin data). Through the collection of CGM, insulin, and pregnancy outcome data, the study will provide important information to understand how diabetes is being managed during pregnancy. These data will provide much needed evidence to guide modern management of diabetes during pregnancy with a goal of improving care and outcomes.

Type 1 diabetes (T1D) management during pregnancy is a critical area as pregnancy complicated by T1D is still associated with a markedly elevated risk of maternal and fetal complications. Because the risk of these complications is tightly linked to glucose levels, guidelines recommend lower glycemic targets than in non-pregnant individuals to optimize pregnancy outcomes. Hybrid closed loop (HCL) insulin delivery systems may aid in glycemic management during pregnancy, but options for use of HCL during pregnancy are limited and present challenges as systems are not approved for use in pregnancy and do not target pregnancy glycemic goals. Thus, pregnant individuals with T1D and their clinicians must consider off-label use of HCL systems with suboptimal glycemic targets. To get closer to pregnancy glycemic targets, individuals may adjust the way they use the system, but there is insufficient evidence to understand the impact of HCL systems available in the US on pregnancy glycemic metrics and pregnancy outcomes.

To address these gaps in evidence, we propose an observational study that will enable systematic assessment of HCL system use in pregnancies complicated by T1D. The focus of this study is to assess glycemic outcomes measured by continuous glucose monitors and clinical pregnancy outcomes associated with use of HCL versus other insulin delivery methods. Data collected from this study will provide important information about how individuals in the United States are managing their diabetes during pregnancy and will help us to identify factors that could minimize the risk of diabetes-associated pregnancy complications and reduce the burden that comes with managing T1D in pregnancy.

Pregnant individuals throughout the United States will be enrolled in this remote observational study. Participants will be asked to share details about their diabetes and pregnancy. Participants will also be asked to share diabetes device data from their continuous glucose monitor (CGM). Participants who use an insulin pump or connected insulin pen may also be asked to share these data.

Inclusion Criteria:

1. Age ≥18 years
2. Clinical diagnosis of presumed T1D for at least 6 months duration
3. Less than 15 weeks gestation at time of enrollment based on due date from provider
4. Planned CGM use on a regular basis (e.g., ≥10 out of 14 days) and willing to continue using CGM regularly with no plans to discontinue CGM use during the study
5. Following intensive insulin therapy regimen defined as basal-bolus delivery via an insulin pump (including a closed loop system) or multiple daily injections (MDI)
6. Have access to technology that may be required to complete study questionnaires and share diabetes device data.
7. Resident of the United States and plans to reside in the U.S. for the duration of the study
8. Comprehends written and spoken English or Spanish
9. Willing and able to provide informed consent, complete surveys and provide the device data that are part of the protocol

Exclusion Criteria:

1. Multiple pregnancy
2. Current renal dialysis or plan to begin renal dialysis during the study
3. History of liver cirrhosis
4. Active cancer treatment with systemic chemotherapy
5. Current participation in other studies involving an investigational insulin delivery device or planning to participate in an investigational insulin delivery device study during pregnancy
6. Prior participation in this study

Pregnant adults with type 1 diabetes from across the United States who use a continuous glucose monitor.