Women living with type 1 diabetes (T1D) often face unpredictable changes in blood sugar levels due to hormonal fluctuations — a long-observed but underresearched clinical concern. To address this issue, pediatric endocrinologist Eda Cengiz, MD, MHS, a UCSF Benioff Professor of Children's Health, is advancing efforts to bring women more scientific clarity and personalized solutions.

Women spend nearly 30 years of their lives going through menstrual cycles, and many experience changes in insulin action and sensitivity each month, often without understanding why their glucose levels suddenly fluctuate. “It becomes a challenging blood sugar guessing game for women with diabetes,” says Dr. Cengiz, who also directs UCSF’s Pediatric Diabetes Program. “This unpredictability leads to frustration, uncertainty, and suboptimal blood glucose control.”

After years of hearing these concerns and observing blood sugar fluctuations in the clinic, Dr. Cengiz and her team conducted insulin action studies showing that insulin’s blood sugar-lowering effect can decrease up to 40% during different menstrual cycle phases. This considerable variation prompted the team to explore ways to tailor and deliver insulin for each individual’s needs.

Dr. Cengiz’s team is testing automated insulin delivery (AID) systems with integrated algorithms that account for hormonal changes. These systems — which consist of a continuous glucose sensor that tracks blood sugar, an insulin pump, and a “smart” algorithm that uses artificial intelligence or machine learning to make data-informed decisions — automatically adjust insulin levels throughout the day. They are designed to keep blood sugar in a healthy range and reduce the daily effort of managing diabetes.

“These systems function on autopilot, but without factoring in monthly changes in insulin sensitivity, they fall short of being truly personalized,” Dr. Cengiz says. “Women's glycemic responses vary more with hormonal changes, which affects insulin needs and treatment efficacy. Our research allows us to build algorithms and therapies tailored to these fluctuations, enabling safer and more effective use of automated insulin delivery systems. We’re working to inform the system that it’s managing care for a woman so it can adjust insulin delivery much more accurately.”

Dr. Cengiz says moving beyond "one-size-fits-all" models ensures that women, especially those from underrepresented or high-risk populations, receive equitable and effective treatment based on their unique needs.

With support from the Breakthrough T1D Foundation, the study will enroll adult women experiencing menstrual cycle-related glucose fluctuations to determine whether individualized adjustments in AID systems can improve diabetes treatment. 

While current studies focus on menstrual cycle-related insulin variability, Dr. Cengiz hopes to expand her work addressing diabetes care for women in perimenopause and menopause, when insulin sensitivity may change significantly. 

“Clinical trials often exclude older women with diabetes or do not analyze menopause status, leaving providers without clear evidence to tailor therapies for [these] women,” Dr. Cengiz says. 

“Postmenopausal women face a higher risk of cardiovascular disease, osteoporosis, and depression, all of which can interact with diabetes and compound management challenges,” she explains. “Targeted research and care models could fill critical gaps, improving outcomes and quality of life for a rapidly growing and historically overlooked group of women. We are seeking grant funds and donations to conduct research studies in women’s health to address this important gap in medicine. 

“The overall goal is to improve their lives and prevent future complications with precision diabetes treatments.” 

This research is expected to lead to fully automated insulin delivery systems for sex-specific precision treatment, which involve even more innovative algorithms because they rely entirely on sensor input and artificial intelligence without manual intervention.

“Fully automated systems will bring us one step closer to precision medicine,” Dr. Cengiz says. “Women’s health, especially in diabetes care, has been underfunded and understudied, and we need to close those gaps.

As Pediatric Diabetes Program director, Dr. Cengiz works to align care across UCSF’s campuses and expand access to diabetes technology and clinical trials in underresourced East Bay communities.

“Social determinants of health matter. Prescribing insulin and diabetes technology devices isn’t enough if patients can’t afford them,” she says. “That’s why we’re working to expand access to diabetes technology tools such as insulin pumps, sensors, and education in communities that need them most.”

While federal funding plays a role, much of Dr. Cengiz’s work wouldn’t be possible without philanthropy. “I’m incredibly grateful for the support of donors and the endowed chair I hold,” she says. “In a funding climate where even using the word ‘women’ in grant proposals can be a barrier, donor support is essential to moving this work forward.”

Dr. Cengiz hopes to grow UCSF’s role as a national leader in diabetes technology innovation, with women’s health at the center