Co-founder and Medical Director of Twig Fertility, Dr. Rhonda Zwingerman is a physician and reproductive endocrinology and infertility (REI) specialist.
She completed medical school at Queen’s University, OBGYN residency at the University of Alberta, and her Masters and REI fellowship at the University of Toronto. Her clinical and research interests include endometriosis, reproductive genetics including preimplantation genetic testing, and early pregnancy care of fertility patients.
Having gone through IVF herself, she understands first-hand how difficult it is to be on a fertility journey. She is committed to modernizing fertility care through the use of best-in-class technologies and to creating clinics that bring like-minded people together to provide Canadians with the comprehensive and compassionate fertility care that they deserve.
An avid musical theatre buff, Dr. Zwingerman sits on the board of the Musical Stage Company, Canada’s leading and largest non-profit dedicated to musical theatre. When not working, spending time with her family or at the theatre, she’s planning her next theatre-related trip to NYC.
Dr. Rhonda Zwingerman
Medical Director & Co-Founder
Dr. Ruth Ronn brings a wealth of experience from her work on the frontlines of fertility – both in Canada and abroad. A Royal College certified Obstetrician Gynaecologist and Reproductive Endocrinology & Infertility (REI) specialist, she is a graduate of McGill Medical School and trained in Obstetrics and Gynaecology at Queen’s University.
Dr. Ronn completed her Reproductive Endocrinology & Infertility (REI) Fellowship at Mount Sinai Hospital, University of Toronto, and received her Masters in Public Health at Johns Hopkins University. She has trained with world leaders in infertility both in Israel and in Canada and is the recipient of numerous scholarships, awards, and research grants.
Dr. Ronn has pursued a variety of research initiatives and continues to carefully follow challenges in fertility preservation and disparities in fertility care. She has published in peer reviewed medical journals, presented at national and international conferences, and has helped author the Canadian Guidelines on Fertility Preservation. She is currently working on national guidelines towards inclusive fertility care for sexual and gender minorities.
In addition to her daily practice as an infertility specialist, she is passionate about yoga, outdoor activities, and travel.
Dr. Ruth Ronn
Deputy Medical Director
Dr. Alyson Digby is a Reproductive Endocrinology and Infertility Specialist with a dynamic background that blends science, art and well-being. Originally from coastal Halifax, Nova Scotia, she holds two Bachelor’s Degrees in Behavioural Neuroscience and Fine Arts from McGill and NSCAD, respectively. Dr. Digby attended Medical School at Dalhousie University, where she then went on to complete her residency in Obstetrics and Gynaecology. Come full circle, she returned to McGill for a Fellowship in Gynaecologic Reproductive Endocrinology and Infertility.
Amidst her formal medical training, Dr. Digby completed Akhanda Yoga Teacher Training, which deepened her perspective on the mind-body connection. Dr. Digby is unwavering in providing compassionate care, rooted in the values of her interdisciplinary learnings.
Dr. Alyson Digby
Reproductive Endocrinology & Infertility Specialist (REI)
Dr. Ganer Herman is a Reproductive Endocrinologist and Infertility (REI) Specialist with extensive clinical and academic experience, having co-authored nearly 100 research papers in gynaecology, obstetrics and reproductive medicine.
Originally from Israel, Dr. Ganer Herman is a graduate of Ben Gurion University. She did her residency in Obstetrics and Gynaecology at the Edith Wolfson Medical Centre in Tel Aviv and practised reproductive medicine for nearly two years before completing her REI Fellowship Program at McGill University in Montreal, Quebec.
Dr. Ganer Herman is a highly regarded practitioner who is dedicated to delivering top-tier care to all patients and is passionate about helping people achieve their family building goals. When she’s not seeing patients or contributing to literature on reproductive medicine, Dr. Ganer Herman leans into artistic pursuits and is a talented pianist.
Dr. Hadas Ganer Herman
Reproductive Endocrinology & Infertility Specialist (REI)
Dr. Ryan Fitzpatrick is a Urologist with subspecialty fellowship training in Male Infertility and Andrology. He completed medical school at Queen’s University, Urology residency at the University of Ottawa and Infertility Fellowship Training at the University of Toronto.
Dr. Fitzpatrick’s clinical interests surround optimizing male fertility and helping maximize patients success going into any assisted reproduction treatments. He is committed to improving the societal barriers around requiring fertility care and providing complete and compassionate fertility care to all of his patients.
When not in the clinic, Dr. Fitzpatrick is an avid traveler and a big Raptors fan.
Dr. Ryan Fitzpatrick
As the Lab Director at Twig Fertility, Christine brings to the team a diverse and multi-faceted background in fertility and reproductive biology. It is through her passion for evidence-based research and overall exposure to multiple parts of the patient journey, that Christine has meticulously designed our laboratory which incorporates best practices from leading clinics across North America, and intertwines them into workflows that take a holistic view of the entire patient experience.
Her reproductive journey started with a Master’s degree from McGill University where she studied the key factors of embryo implantation. Following her thesis work, Christine entered into the world of fertility as a clinical embryologist and over the course of her career has been part of the teams in three leading fertility clinics in Canada.
Building upon her experiences in embryology, Christine then joined Igenomix, a leading genetic testing service provider specialized in fertility and reproductive health. At Igenomix, Christine set up two laboratory sites and was responsible for overseeing Canadian operations, as well as advising physicians across the US and Canada on genetic services, including endometrial receptivity and microbiome testing.
Christine is a member of the Canadian Fertility and Andrology Society (CFAS), the European Society of Human Reproduction and Embryology (ESHRE) and the Society of Obstetricians and Gynaecologists of Canada (SOGC).
A mother to two young kids and a dog, Zoe, Christine is also a certified yoga instructor and an avid backpacking camper. She is a PADI certified SCUBA diver and has spent time diving and studying blacktip and ragged tooth sharks, supporting research in Aliwal Shoal, South Africa.
Christine Sykas Yeh
Michelle is a registered nurse with over 15 years experience in obstetrics, gynaecology and fertility, focused on providing the highest level of care and compassion to all patients and their families.
She completed a Bachelor of Science in Nursing at Seneca College/York University Collaborative Program, a Masters of Nursing degree at Athabasca University as well as a certificate in Reproductive Endocrinology and Infertility from the American Society of Reproductive Medicine. Michelle is also a member of the Canadian Fertility and Andrology Society (CFAS).
A mother of twins, Michelle also enjoys hiking, cycling, spending time outdoors, studying and playing with her kids.
Clinic & Nurse Manager
Meet Jocelyn, our Assistant Clinic Manager. Driven by the desire to make a meaningful impact, Jocelyn is committed to supporting people on their fertility and family building journeys with care and understanding.
She completed an Honours Bachelor’s of Science Degree with a focus in Biology at Toronto Metropolitan University (formerly Ryerson University) and is dedicated to delivering empathetic healthcare to all patients. Jocelyn brings valuable experience working in dynamic and challenging environments from her tenure at Animal Health Partners, an Emergency and Speciality Veterinary Hospital, where she honed her skills in handling critical situations with compassion.
Outside of the clinical sphere, Jocelyn is a dance teacher, sharing her passion for movement with students of all ages. She also enjoys hiking and going for jogs with her Labrador, Molly.
Assistant Clinic Manager
Erin brings to Twig over ten years of experience, seven as a primary care Nurse Practitioner. She completed a Bachelor of Arts in Psychology and Women’s Studies and a Bachelor of Science in Nursing at Trent University, and a Master of Nursing at Athabasca University. Erin brings with her a deep expertise in inclusive reproductive and sexual health care serving people of all genders and sexualities.
Meet our Nurse Practitioner, Daria Gefrerer, who joins the Twig Fertility team full time. Daria holds a Specialist Degree in Human Biology: Health and Disease from the University of Toronto, after which she pursued her Bachelor of Science in Nursing from York University, culminating in a Master of Nursing/ Nurse Practitioner Degree from the University of Toronto.
Prior to joining Twig Fertility, Daria had worked for twelve years in the areas of labour and delivery, and high risk obstetrics. After pursuing her Nurse Practitioner, she held a variety of roles, including taking care of women in the prenatal and postpartum periods.
When not at work, Daria runs after her busy toddler, enjoys tending to her vegetable garden, baking, and entertaining friends and family.
Christina is a dual-certified Nurse Practitioner in Adult and Primary Care, with over a decade of experience in managing complex chronic diseases, mental health, and refugee health. She is passionate about women’s health and is dedicated to supporting individuals and couples during the pivotal moments of planning and growing their families.
Christina holds a Bachelor of Science in Nursing from Toronto Metropolitan University (formerly Ryerson University), where she also minored in psychology, laying a solid foundation for her compassionate approach to patient care. She then went on to complete her Master of Nursing with a speciality as an Adult Care Nurse Practitioner at the University of Toronto followed by the Primary Care Nurse Practitioner program at Athabasca University.
Her career as a care provider has been marked by a deep commitment to diverse areas of healthcare. Christina previously worked as a recovery room nurse at Mount Sinai Hospital, a Nurse Practitioner at Community Health Centre as well as having dedicated time to Indigenous health work on First Nations Reserves, reflecting her broad spectrum of clinical expertise and cultural sensitivity.
Outside of her professional life, Christina has several interests from cooking to crafting and dabbles in various activities from pickleball to needlepoint. She’s a lover of animals, a chocolate enthusiast, and always up for a good laugh.
Sarah brings her cultivated expertise and worldview to her role at Twig, with eight years of postgraduate education and over a decade of experience working in healthcare.
With an Honours Bachelor’s of Science Degree from McMaster University, Sarah expanded her scope of studies by pursuing a Bachelor’s of Science in Nursing at University of Toronto. She then completed her Masters of Nursing and Primary Health Care Nurse Practitioner Degree from the recently renamed Toronto Metropolitan University (formerly Ryerson).
Sarah’s early career is marked by a decade of service at St. Michael’s Hospital working as a registered nurse. Spent the latter five years of her tenure providing critical care to patients in the Trauma and Neurosurgery ICU. She transitioned to primary care at Black Creek Community Health Care as a Nurse Practitioner before joining Twig.
Beyond her work in-clinic, Sarah has volunteered globally providing compassionate care in countries like Guatemala, Ecuador and Thailand. Sarah loves travelling, camping and cherishing moments with her German Shepherd, Simba.
Heather is a certified Genetic Counsellor with 10 years’ experience in diverse clinical and academic settings. As Twig’s in-house genetic counsellor, Heather will help empower you to navigate and make informed decisions about your genetic testing options and results at every stage of your family-building journey. Her approach is compassionate, inclusive, evidence-based, and always centred on your unique values, goals, and circumstances.
Heather earned her Master’s of Science in Genetic Counselling from the University of Toronto and is certified by both the Canadian and American Boards of Genetic Counselling. She began her career at the world’s first psychiatric genetic counselling clinic in Vancouver BC, where her research work focused on perinatal and postpartum mental health. Heather’s clinical experience has made her passionate about removing barriers for fertility patients to access comprehensive preconception and prenatal genetic services in the context of an integrated and supportive care team, and she is excited to have the opportunity to put this into action at Twig.
Outside of the clinic, you can find Heather spending quality time with family and friends, staying active with hiking and rock climbing, and volunteering with Shelter Movers to help survivors of abuse transition to safer lives.
As the Reproductive Counsellor at Twig, Elisa will support and empower patients during their fertility journeys through individual, relationship, and group checkin-ins and counselling. She fosters an anti-oppressive and trauma-informed practice founded on non-judgement, creativity, and kindness. She is experienced working with members of the LGBT2SQ+ community, with non-traditional families, and has training in group work, narrative therapy, emotionally-focused therapy (EFT), and cognitive-behavioral therapy (CBT). When not at Twig, Elisa works as a relationship and sex therapist in private practice.
Elisa is a Registered Social Worker with the Ontario College of Social Workers and Social Service Workers (OCSWSSW). She earned her Master’s in Social Work from Loyola University Chicago and is a trained advocate for survivors of sexual assault and gender-based violence. She is a member of the Ontario Association of Social Workers (OASW), Canadian Fertility and Andrology Society (CFAS), the International Association of Social Work with Groups (IASWG), and volunteers at Stella’s Place, a mental health centre for young adults in Toronto.
In her free time, Elisa is a musician who learns and performs traditional world harmony singing, old-time music, and Appalachian clogging. She is a quilter, a birder, a vacuumer of dog hair, and is working on planting a pollinator-friendly garden in her yard.