Our Care Team

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. 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. 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. 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. Alice Buwembo is a Reproductive Endocrinology and Infertility Specialist (REI) who joins Twig with a passion for helping people achieve their dream of conceiving. Her gentle approach focuses on empowering patients along their journey, using evidence-based medicine to provide compassionate, personalized fertility care.

Originally from Saskatchewan, Dr. Buwembo pursued her undergraduate studies in Biomedical Sciences at the University of Ottawa. She then completed a Master’s in Neuroscience at McGill University before attending medical school in Cork, Ireland. Her medical training continued with a residency in Obstetrics & Gynaecology and a fellowship in Gynaecologic Reproductive Endocrinology & Infertility, both at McMaster University.

Beyond her academic and professional pursuits, Dr. Buwembo enjoys spending quality time with her family, attending concerts, and exploring new foods and cultures through travel. She’s an avid Formula 1 fan and hopes to attend a Grand Prix at one of the iconic circuits around the world.

Dr. Argyrios (Argy) Kolokythas joins Twig as a Reproductive Endocrinology and Infertility Specialist (REI). Originally from Greece, Dr. Kolokythas earned his Medical Degree at the University of Athens, completed his Obstetrics and Gynaecology Residency in Switzerland, and pursued his Fellowship in Gynaecologic Reproductive Endocrinology and Infertility at McGill University in Montreal.

In addition to his medical training, Dr. Kolokythas holds two Master’s Degrees: an MSc in Health Economics, Policy, and Law from Erasmus University in the Netherlands, and an MSc in Evidence-Based Health Care from Oxford University in the United Kingdom.

Having lived in several countries, Dr. Kolokythas embraces the richness of diverse cultures, fostering empathy, acceptance, and open-mindedness in his approach. Passionate about building meaningful relationships with his patients, he is committed to helping individuals and couples create their families, offering compassionate, personalized care throughout their journey.

Outside of clinical life, Dr. Kolokythas enjoys traveling, playing tennis, and watching movies. A true linguaphile, he speaks Greek, English, German, French, and Italian. Always up for a challenge, whether it’s practicing a new skill, mastering a board game, or learning a new language Dr. Kolokythas views every experience as an opportunity for growth.

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.

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.

Meet our compassionate Clinic Manager, Helen. With a solid foundation in nursing and a wealth of experience in fertility and sexual health, Helen brings a well rounded approach of expertise and empathy to our team.

Graduating from the Collaborative Program at Centennial College and Toronto Metropolitan University (Ryerson) with a Bachelor of Science in Nursing, Helen embarked on a professional journey marked by a commitment to patient-centered care. Throughout her career, she has focused on providing personalized and compassionate care to individuals navigating the complexities of fertility and sexual health.

At the heart of Helen’s practice lies a deeply held belief in the importance of patient-centered care. She understands that each patient’s journey is unique and deserving of individualized attention. Whether it’s offering guidance, providing support, or lending a listening ear, she is dedicated to ensuring that every patient feels heard, valued, and empowered throughout their fertility journey.

Outside work, Helen enjoys solving crosswords, indulging in good food, and guilty pleasures like bad reality TV. She is also passionate about animal welfare, having volunteered with a local dog rescue on a spay and neuter trip to the Dominican Republic.

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.

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.

Nicole is committed to delivering evidence-based care tailored to the unique needs of each patient she sees. She earned her Bachelor of Science in Nursing from Ontario Tech University and began her nursing career in Oncology at SickKids, where she gained invaluable experience and developed a deep commitment to patient care. Driven by academic interest and a passion for advanced practice, she pursued a combined Master of Nursing Degree and Primary Health Care Nurse Practitioner Certificate at Toronto Metropolitan University (formerly Ryerson).

As a Nurse Practitioner, Nicole built her foundation through providing primary care in the rural setting of Northumberland, Ontario before moving to Toronto where she focused on chronic disease management and prevention, mental health, and reproductive health. Her extensive background allows her to provide comprehensive, empathetic care where she prioritizes creating a safe and inclusive space for all patients.

Outside of her professional life, Nicole enjoys spending time with her husband and their Samoyed puppy, Penny. She is an avid football fan, cheering for the Buffalo Bills, and loves staying active through hiking and exercise classes in the city.

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.

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.

Madeleine is a Nurse Practitioner with expertise in reproductive and women’s health. She obtained a Bachelor of Science in Nursing at Queen’s University and completed the combined Masters of Nursing/Nurse Practitioner program at the University of Toronto, specializing in Global Health.

Madeleine is committed to providing compassionate, holistic fertility care. She has extensive experience working in acute care settings with vulnerable populations, including high-risk labour and delivery at Mount Sinai Hospital and in remote Indigenous communities. Prior to joining Twig, Madeleine was a Nurse Practitioner at the Bay Centre, an inclusive sexual health clinic at Women’s College Hospital.

In her free time, Madeleine enjoys being active and traveling. An adventurous spirit, she once swam in the Arctic Ocean while working in the Northwest Territories and has sailed across the Baltic Sea.

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.

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.

Gena is a certified Genetic Counsellor with extensive experience working with diverse patient groups in both Canada and the United States. She has made significant contributions to the fertility community as the former genetics liason for the American Society for Reproductive Medicine (ASRM) where she authored the genetics section of its 2021 guidelines for egg, sperm and embryo donors. 

Gena holds a Master’s Degree in Genetic Counseling from the University of British Columbia and certification from the American Board of Genetic Counselling. She began her career in St. John’s, Newfoundland working with families with rare diseases before specializing in fertility.

Prior to joining Twig, Gena spent nearly eight years working remotely for ORM Fertility in Portland, Oregon where she focused on preconception genetic counseling, covering areas such as preimplantation genetic testing (PGT), embryo mosaicism, expanded carrier screening, third-party reproduction, and analyzing family histories. 

In addition to her career in fertility genetics, Gena and her husband own a brewery in a small town in Saskatchewan. She enjoys reading, baking, listening to podcasts and spending time with her young son in their new home in the prairies.