Developing healthy, trusting relationships with my patients is a passion of mine. Preventative medicine is key to a long, healthy life. In my free time I enjoy spending time with my french bulldog, Lilo, playing video games, hiking, traveling, and kayaking.

Dr. O'Brien is Medical Director of Maternal-Fetal Medicine at South Shore Health. 

As a Maternal-Fetal Medicine physician, I am dedicated to caring for women and families navigating high-risk and medically complex pregnancies with expertise, compassion, and individualized attention. 

I strive to integrate evidence-based medicine with a holistic approach that recognizes the physical, emotional, and social factors that shape each patient’s experience. 

I am also committed to advocating for equitable healthcare and improving access and outcomes for marginalized and underserved communities.

My goal is to educate, support, and empower women to make choices about their health that they feel good!

I believe in providing women with education and options that empower them to make healthy decisions that contribute to better health for themselves and their families. I see the importance and benefit in a model of shared decision making. When I'm not midwifing it up I like to write, read, run, bake and hang with my kids and husband!

I also blog for South Shore Health. Check out my blog posts!

My goal is to communicate effectively with patients so they have the understanding to make informed decisions for their own health. It is very humbling to work in a field that involves caring for others. I am continually inspired by my patients and the ability grow a patient-provider relationship over time.  As health care professionals, patients are the focal point of all that we do. Outside of work I enjoy being active outdoors, playing piano, and spending time with loved ones. 

My treatment philosophy is to help educate individuals on their role in disease prevention and develop relationships with patients—working as a team to manage both chronic and acute health issues. I believe that each individual has their own unique set of circumstances that influence their health and working together to overcome barriers is an essential part of providing healthcare. I consider it a privilege getting to know patients and families and always look at the big picture when caring for individuals. Outside of work I love spending time with my family, going to the beach, gardening and hiking. I am teaching myself how to ice skate so I can play hockey with my boys! 

William Tollefsen, MD is the EMS and MIH Medical Director for South Shore Health. Dual-boarded in Emergency Medicine and EMS Medicine, Dr. Tollefsen works clinically as an Emergency Physician at South Shore Health in addition to his role as EMS Medical Director.

One of few physicians in the country to receive the prestigious "FAEMS" recognition, Dr. Tollefsen is also the Medical Director for OEMS Region IV, serving 61 cities and towns of the Metro-Boston EMS Council. As the current EMS Medical Director for eight municipal and three private ambulance services on the South Shore, Dr. Tollefsen interacts and provides oversight for over 400 Paramedics.

Dr. Tollefsen graduated from New York Medical College and completed residency training in Emergency Medicine at Harvard University, Brigham and Women's, and Massachusetts General Hospital. He completed a fellowship in Emergency Medical Services and Critical Care Transport at the University of Massachusetts, where he worked as an Emergency Physician and Flight Physician for UMASS LifeFlight. He completed an MBA at the Isenberg School of Management at UMASS Amherst, and holds a Master of Medical Science degree from the Boston University School of Medicine.

A former pre-hospital provider, he is actively involved in EMS system design, paramedic education and Critical Care Transport Systems. He works closely with multiple EMS, Fire and Law Enforcement agencies throughout Massachusetts.

His research interests include systems of care, resuscitation, airway management, and paramedic education.

As the Medical Director of Addiction Medicine at South Shore Health, I work to tackle the defining medical challenge of our time: Substance use and alcohol use disorder.

In addition to seeing adult patients at South Shore Hospital, I work with colleagues across South Shore Health to develop and implement a comprehensive addiction medicine treatment program. This program will connect patients with the resources they need to manage substance use disorder, no matter if they come to us through the Emergency Department, primary care, or another setting. Additionally, I serve as Medical Director for Spectrum Health System's opioid treatment program, ATS/detox, CSS, and therapeutic community in Weymouth.

Prior to my work at South Shore Health, I helped launch the Bridge Clinic at Boston Medical Center, which connected patients with treatment options for substance use disorder. I also served as Medical Director for Spectrum Health Systems’ Opioid Treatment Program in Weymouth.

In my spare time, I enjoy baseball, reading fiction, snowboarding, and cooking.