Pregnant woman

DAN Women & Babies Team


Dr. Stefania Ronzoni

Staff physician

Sunnybrook Health Science Centre
2075 Bayview Avenue
Toronto, ON M4N 3M5

Phone: 416-480-4920

Administrative assistant: Kelly Costa
Phone: 416-480-4920
Fax: 416-480-4933
Email: kelly.costa@sunnybrook.ca

Clinical profile

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  • Preterm birth
  • Fetal ultrasound (prenatal screening and early diagnosis of fetal anomalies)
  • Maternal nutrition in pregnancy

Research profile

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  • MD, 1994 University of Milan, Italy
  • Specialist in obstetrics and gynecology, 1998 University of Milan, Italy
  • PhD in science of prenatal development, 2002 University of Milan, Italy
  • Subspecialist in maternal fetal medicine 2017, University of Toronto, Canada

Appointments and Affiliations

  • Associate scientist, evaluative clinical sciences, DAN Women & Babies Research Program, Sunnybrook Research Institute
  • Staff physician, division of maternal fetal medicine, department of obstetrics and gynecology, Sunnybrook Health Sciences Centre
  • Associate Professor, department of obstetrics and gynaecology, faculty of medicine, University of Toronto

Research foci

  • Fetal and maternal metabolism
  • Pathophysiology of preterm birth
  • Education in ultrasound
  • Early fetal anatomy and prenatal screening

Research summary

During her PhD in the science of prenatal development in 2002, Dr. Ronzoni produced a significant body of research in the area of maternal and fetal metabolism in normal pregnancy and in pregnancies complicated by intrauterine growth restriction. Further scientific activities since then have been more clinically oriented, focusing on neonatal outcomes of IUGR fetuses with different classes of severity, demonstrating that intrauterine growth curves are more predictive of perinatal outcomes compared with neonatal birthweight standards and on feto-maternal blood flow ultrasound indices during laparoscopic surgery in pregnancies, showing that during pregnancy there is a singular hemodynamic adaptation that minimized the effect of the pneumoperitoneum required for laparoscopic procedures.

Dr. Ronzoni is also interested in maternal nutrition during pregnancy and she is co-author of the book Nine Months of Recipes. Healthy and Tasty Foods to Eat During Your Pregnancy, Publisher: Ponte alle Grazie, Italy

After relocation to Canada for family reasons, Dr. Ronzoni was awarded a transitional career opportunity at Mount Sinai Hospital, University of Toronto. Initially as a fellow in advanced obstetrics and later in maternal fetal medicine she studied the impact of obesity on successful induction of labor showing that elevated BMI is an independent factor in determining the increased rate of cesarean section. She successfully obtained a translational research grant to study the maternal endotoxin concentration in peripheral blood, and other inflammatory biomarkers, for the prediction of the latency period to delivery in women with preterm premature rupture membranes. Finally, she participated in a Meta-analysis of Progestogens to maintain uterine quiescence following arrested preterm labor.

Moreover, she coordinated a project of innovative learning based on the use of an ultrasound obstetrical simulator for OBGYN residents. This training approach has now been formally embedded into the University of Toronto residency training curriculum.

Recent publications

  • Ronzoni S, Rosen H, Melamed N, Porat S, Farine D, Maxwell C. Maternal Obesity Class as a Predictor of Induction Failure: A Practical Risk Assessment Tool. Am J Perinatol. 2015 Dec;32(14):1298-304.
  • Ronzoni S, Melamed N, Kingdom JC, Ryan G, Jaeggi E, Windrim RC. Prenatal diagnosis of inguinoscrotal hernia associated with bowel dilatation: a pathogenetic hypothesis. Prenat Diagn. 2015 Nov;35(11):1151-3.
  • Palacio M, Ronzoni S, Sancez L, Murphy K. Progestogens as Maintenance Treatment in Arrested Preterm Labor: A Systematic Review and Meta-analysis. Obstetrics and Gynecology 2016 Nov;128(5):989-1000.
  • Rosen H, Windrim R, Lee YM, Gotha L, Perelman S, Ronzoni S. Simulator Based Obstetric Ultrasound Training: A Prospective Randomized Single-Blinded Study. Journal of Obstetrics and Gynecology Canada 2017 Mar;39(3):166-173.