Meet Our Fertility Doctors & Reproductive Endocrinology Experts in California

Dr. Peter Uzelac brings an exceptionally rare and integrated background in reproductive medicine, maternal-fetal medicine, and IVF lab directorship. As both a practicing fertility doctor and scientific leader in the embryology lab, his career spans all critical stages of the fertility care continuum – from complex diagnosis and advanced surgical interventions to cutting-edge lab techniques such as in vitro maturation (IVM), assisted hatching, and cryopreservation of embryos.

Education and Clinical Training

• July 1998 – June 2002
  Residency in Obstetrics and Gynecology
  Loma Linda University–White Memorial Medical Center, Los Angeles, CA 90033
• July 2002 – June 2006
  Assistant Professor of Clinical Obstetrics and Gynecology
  Division of Maternal-Fetal Medicine, University of Southern California / Keck School of Medicine, Los Angeles, CA

• Feb 2004 – Feb 2005
  Co-Director, Fellowship in Maternity and Child Health Development
  Department of Family Medicine, USC / Keck School of Medicine, Los Angeles, CA
• July 2006 – June 2009
  Fellow and Clinical Instructor in Reproductive Endocrinology and Infertility
  (Division Chief: Dr. Steven Nakajima)
  University of Louisville, Louisville, KY 40202
• July 2009 – Present
  Medical Director – Marin Fertility Center, a premier fertility clinic in the Bay Area known for excellence in fertility preservation and innovation in egg freezing technologies.

• July 2018 – Present
  Laboratory Director – MFC’s state-of-the-art embryology lab, specializing in advanced IVF, egg retrieval, and embryo freezing protocols.

A Fertility Specialist Who Sees Through the Patient’s Eyes

As the founder and guiding force of Marin Fertility Center for over 15 years, Dr. Uzelac offers a perspective that few fertility specialists can match – a triple-role blend of clinician, IVF lab director, and practice administrator.

This unique position allows him to address each fertility journey not only from the medical standpoint but also from emotional and logistical angles. His leadership fosters continual innovation in lab practices and clinical protocols, ensuring excellence in outcomes for patients pursuing donor eggs, donor sperm, fertility surgery, or preimplantation genetic testing.

Dr. Uzelac’s patient-centric philosophy empowers individuals at every step – whether they are undergoing fertility testing, exploring egg freezing, or receiving complex evaluations for ovarian reserve or endometriosis and fertility concerns. His integrated care model reflects the evolving needs of modern families in Santa Rosa, the Bay Area, and beyond.

Foundations in Maternal-Fetal Medicine & Fertility Science

Before formally specializing in reproductive endocrinology, Dr. Uzelac spent four transformative years with the University of Southern California’s Division of Maternal-Fetal Medicine. There, he cared for families facing high-risk pregnancies with severe congenital anomalies, deepening his interest in the prenatal origins of disease and the lifelong implications of early gestational exposures.

This experience led to his publication of peer-reviewed research on prenatal hormone dysregulation and its link to future endocrine dysfunction – an important foundation that informs his current focus on helping patients not just conceive, but build healthy families through strategies like cryopreservation of eggs and personalized embryo selection.

A Personal Turning Point and the Birth of a Vision

In 2006, Dr. Uzelac’s son was born with a significant developmental anomaly requiring urgent surgery. When the medical community delivered fragmented and contradictory guidance, his family was left overwhelmed and uncertain. They eventually found successful treatment at a center across the country – an ordeal that transformed Dr. Uzelac’s professional mission.

This deeply personal chapter ignited his unwavering commitment to patient advocacy and reinforced the importance of hope, persistence, and personalized care. Just three years later, in 2009, he founded Marin Fertility Center – a space where people who feel lost or dismissed by traditional systems can receive expert, compassionate care.

Now, over a decade later, MFC stands as a nationally recognized hub for fertility preservation, complex IVF treatment, and advanced diagnostics – shaped by a leader who continues to innovate from both the exam room and the embryology lab.

As a highly respected fertility specialist and educator, Dr. Uzelac actively contributes to medical literature and the peer review process. His extensive authorship focuses on reproductive endocrinology, fertility preservation, and best practices in fertility surgery and IVF care.

Book Chapters

• Repair of Cesarean Section Scar, in “Operative Techniques in Gynecologic Surgery: Reproductive Endocrinology and Infertility”, Wolters Kluwer, 2017.
• The Role of In Vitro Maturation in Fertility Preservation, in “Oncofertility Medical Practice”, Springer, 2012 – highlighting clinical innovations in in vitro maturation (IVM) and cryopreservation of eggs.
• Several key chapters in McGraw-Hill’s “Current Obstetric & Gynecologic Diagnosis & Treatment” (2006), including topics on early pregnancy risks, vaginal bleeding, and labor complications.
• Co-author of the chapter on avoiding triplet pregnancy in assisted reproduction – an issue closely linked to embryo transfer and assisted hatching protocols in IVF.

SOAP Medical Series (Blackwell Science, 2004–2006)

Dr. Uzelac co-authored educational texts for physicians across multiple specialties:

• “SOAP for Obstetrics and Gynecology”
• “SOAP for Pediatrics”, “Emergency Medicine”, “Family Practice”, “Orthopedics”, “Cardiology”, “Internal Medicine”, “Neurology”, “Urology”

These contributions reflect his deep commitment to clinical education in women’s health and fertility medicine.

Dr. Uzelac’s award-winning research in reproductive endocrinology, IVF lab technologies, and embryology labprotocols has been recognized internationally. His work focuses on enhancing success rates in egg retrieval, oocyte maturation, and embryo freezing – with a consistent emphasis on safety and personalization.

Research Highlights & Presentations

• Development of IVM protocols for use in fertility preservation, especially for cancer patients or those with diminished ovarian reserve.
• Validation of truncated IVF cycles for PCOS patients to reduce risk while maintaining success rates.
• Genetic research on Müllerian Inhibiting Substance in follicles and implications for fertility testing.
• Innovations in extracorporeal oocyte retrieval, followed by in vitro maturation and embryo banking.
• Studies on hyperandrogenemia in gestation, contributing to our understanding of hormone regulation during pregnancy.

Dr. Uzelac’s findings have been presented at international conferences such as:

• American Society for Reproductive Medicine (ASRM)
• Society of Gynecologic Investigation (SGI)
• Pacific Coast Reproductive Society (PCRS)

His thought leadership helps advance clinical techniques in donor eggs, donor sperm, and preimplantation genetic testing, benefiting fertility patients across California.

At Home: A Fertility Doctor Grounded in Family and Nature

When he’s not guiding patients through the delicate path of IVF, fertility evaluation, or cryopreservation of embryos, Dr. Uzelac is dedicated to his family – a close-knit group of five who find joy in cooking, gardening, and exploring the world together.

A native of the San Francisco Bay Area, Dr. U thrives outdoors – biking the trails of Mount Tamalpais or climbing in the Sierras. His deep love for nature mirrors the empathy and balance he brings into his medical practice, from Santa Rosa to Marin.

This connection to family, community, and the natural world fuels his dedication to helping others build families of their own through compassionate, science-driven fertility care.

Dr. Joy Brotherton is a fellowship-trained, board-certified OB/GYN with a Focus Practice Designation in Minimally Invasive Gynecologic Surgery (MIGS). She holds a dual academic appointment as Associate Professor at the David Geffen School of Medicine and Clinical Associate Professor of Obstetrics and Gynecology at UCSF School of Medicine. Her clinical leadership and academic contributions align with cutting-edge advances in fertility preservation, fertility surgery, and the treatment of endometriosis and fertility conditions.

With over 14 years of experience in a high-volume academic county hospital in Los Angeles, Dr. Brotherton has trained and mentored hundreds of medical students, residents, and fellows. As Chief of Gynecological Surgical Services and Director of MIGS at Harbor-UCLA, she provided advanced surgical and obstetrical care for thousands of underserved patients.

Her transition to Marin Fertility Center brought her extensive expertise in complex reproductive surgery and her deep commitment to expanding access to fertility preservation – particularly for young, career-oriented women considering egg freezing or facing health conditions affecting their ovarian reserve.

Dr. Brotherton applies her comprehensive understanding of reproductive endocrinology, fertility evaluation, and the surgical management of endometriosis to optimize outcomes for MFC patients pursuing IVF, donor eggs, or personalized care plans supported by thorough fertility testing.

Dr. Brotherton’s upbringing in a culturally rich neighborhood of South Los Angeles shaped her values of inclusivity, hands-on care, and empowerment. After studying Spanish and Portuguese at UC Berkeley and living abroad, she discovered her passion for surgery in medical school.

Years of practicing in academic hospitals revealed for her the importance of patient agency in modern medicine. She believes in a proactive, tech-enabled approach to reproductive wellness – encouraging women to take charge of their fertility through informed decisions such as cryopreservation of eggs, early fertility evaluation, and awareness of lifestyle-related risks.

Now in private practice at MFC, Dr. Brotherton values the opportunity to spend more time with patients, guiding them through critical decisions around egg retrieval, embryo freezing, and the use of donor sperm where needed.

A recognized authority in fertility surgery and MIGS, Dr. Brotherton serves on the Editorial Board of the Journal of Minimally Invasive Gynecologic Surgery (JMIG). She is also the Founder of the Southern California MIGS Collaborative, which supports in-person training labs for young physicians.

Her academic portfolio includes numerous published research papers and national speaking engagements, particularly on topics such as endometriosis and fertility, fertility preservation, and advancements in reproductive surgery. She continues to blend clinical excellence with education at Marin Fertility Center, serving patients from across the Bay Areaand Santa Rosa.

Kirsten Eckert is a board-certified Women’s Health Nurse Practitioner (WHNP) and Certified Nurse-Midwife. She holds a BS from UCLA and a Master’s degree in Nursing from Yale University. Her clinical and academic background reflects a strong foundation in both obstetrics and advanced fertility care, particularly in the areas of donor eggs, donor sperm, and preimplantation genetic testing.

Before joining Marin Fertility Center in 2020, Kirsten worked as a full-scope midwife in Santa Rosa beginning in 2014, providing prenatal, delivery, and women’s health services at Providence and Sutter Santa Rosa hospitals. Her transition into fertility care brought her passion for empowering patients into a new realm – one where her communication skills and compassionate approach now help individuals and couples navigate their paths to parenthood.

At MFC, Kirsten leads the Third-Party Reproduction and Genetic Carrier Screening program. She plays a key role in:

• Educating patients about options involving donor eggs and donor sperm
• Coordinating treatment pathways that include embryo freezing, egg retrieval, and IVF
• Guiding patients through fertility testing, ovarian reserve assessment, and genetic counseling

Her expertise is especially valuable for patients exploring fertility preservation, such as cryopreservation of embryosor cryopreservation of eggs, whether due to medical necessity or lifestyle planning.

Known for her ability to serve as a “medical translator,” Kirsten ensures that every patient fully understands their personalized care plan – from fertility evaluation to advanced treatment options involving the IVF lab.

She currently sees patients at both the Marin and Santa Rosa locations, offering flexible and locally accessible support throughout the Bay Area. Her empathetic and educational approach has made her an invaluable part of the MFC team.

Outside the clinic, Kirsten enjoys gardening, sewing, and adventuring with her husband and two children in Sonoma County – further reflecting her deep roots in the Northern California community.