FDA Approves Automated Insulin Delivery System for Pregnancy in Type 1 Diabetes

The FDA has approved the Control-IQ+ automated insulin delivery system for use in pregnant women with type 1 diabetes, compatible with the t:slim X2 and Mobi insulin pumps. Evidence from the CIRCUIT trial showed that Control-IQ improves time in range compared to standard care, indicating better glycemic control during pregnancy.

“Glycemic goals are tighter during pregnancy,” said Dr. Jordan Pinsker, chief medical officer at Tandem Diabetes Care. “The higher time in the pregnancy-specific glucose range seen with Control-IQ can help improve pregnancy outcomes.”

This expanded label indication for use in type 1 diabetes during pregnancy1 is based on results from the CIRCUIT trial published in Journal of the American Medical Association (JAMA) in October 2025.2 Participants in this multi-center, randomized controlled trial were assigned to use a t:slim X2 insulin pump with Control-IQ technology or to continue their multiple daily insulin injections or insulin pump with continuous glucose monitoring. The Control-IQ group experienced 12.6% more time in the pregnancy glucose target range 63-140 mg/dL, approximately 3 hours more per day, compared to those using their standard therapy, from 16 weeks gestation to the end of pregnancy.1 Maternal and neonatal outcomes were similar in both groups overall but favored those using Control-IQ.

“In the CIRCUIT trial, glycemic improvements were found across all sites and baseline HbA1c ranges, regardless of whether an insulin pump or multiple daily insulin injections were used at enrollment. Marked glycemic improvements occurred within the first week of initiation of Control-IQ that persisted for the duration of pregnancy,” said Dr. Lois Donovan, principal investigator of the CIRCUIT study and Clinical Professor at the University of Calgary.

Tandem Diabetes Care will be performing a series of training events and webinars for healthcare providers related to pregnancy and type 1 diabetes management. The first event will be the Tandem product theater at the American Diabetes Association 2026 Scientific Sessions meeting in New Orleans, Louisiana, in June, discussing the study results.

Results from major studies of Control-IQ technology, including those published by the New England Journal of Medicine in October 2019, August 2020, March 2023, and March 2025, show immediate and sustained glycemic improvements, including more time in range and improved sleep.