- Ovarian follicular development in natural cycles
- Ovarian stimulation
- Ovulation and ovulation induction
- Endometrial Receptivity
- Deveolpment of computer vision tools in women's health
About Roger A. Pierson
Dr. Roger Pierson MS PhD FEAS FCAHS is a University Distinguished Professor in the Department of Obstetrics and Gynecology in the College of Medicine at the University of Saskatchewan. The Distinguished Professorship Program was created to honour and celebrate outstanding achievement in research, scholarly, or artistic work by University of Saskatchewan faculty. He received his BS and MS degrees from Purdue University and a PhD in Reproductive Endocrinology/Physiology at the University of Wisconsin-Madison.
Dr. Pierson is a Fellow of the European Academy of Sciences, Canadian Academy of Health Sciences, and a Past-President of the Canadian Fertility and Andrology Society (CFAS). Dr. Pierson's research has generated more than 550 papers, technical reports, book chapters and abstracts, in addition to more than 40 copyrighted computer programs and 6 patents. Dr. Pierson also has held executive positions in several professional organizations. He served as President of the Canadian Fertility and Andrology Society (CFAS) in 1999-2000 and Chaired the Communications Committee for the Society from 1998-2014.
Dr. Pierson's research is multi-disciplinary and revolves around ovarian follicular development in natural cycles, ovarian stimulation, ovulation and ovulation induction, uterine receptivity and hormonal contraception. Dr. Pierson gave the medical and scientific communities the first ever visualization of human ovulation using ultrasonography in 1990. Subsequent studies on ovarian function in women by Dr. Pierson and colleagues at the University of Saskatchewan were heralded as one of the Top 100 scientific discoveries of 2004 by Discover magazine.
Imaging and image enhancement tools have been developed in Dr. Pierson's laboratory to explain physiological changes over time developed for the analysis of high-resolution ultrasonographic images. They have proven innovative in determining endometrial receptivity, the assessment of ovarian function, as well as, the assessment of ovarian and breast masses. Other areas of research include development of computer software for tissue characterization and analysis of ultrasonographic and MR images, 3-dimensional ultrasonography, early embryo development, automated detection of embryonic anomalies and development of animal model systems for investigation of human reproductive dilemmas.
Dr. Pierson was awarded the University of Saskatchewan Distinguished Researcher award in 2000 and he has received other numerous awards that include: Award of Excellence in Reproductive Medicine for lifetime research achievements from the CFAS, APOG Medical Education Foundation Excellence in Teaching Award for outstanding contributions to the teaching of obstetrics and gynecology; Commemorative Medal for the Centennial of Saskatchewan for his outstanding achievements and significant contribution to society; and, Chatelaine Women’s Health Hero Award with citation for ‘Dedication to advancing women’s health in Canada’. Dr. Pierson was inducted into the Inaugural W. Brett Wilson Center’s Innovator’s Hall of Fame at the University of Saskatchewan in 2009. This award recognized innovators whose work has transformed the way in which people live, work and play around the world and who have reinforced the traditions of success and innovation originating from University of Saskatchewan people.
In addition to his academic work, Dr. Pierson is the founder and Chief Scientific Officer of the Synergyne Group of Companies. He is the innovator of Matris™, an image analysis tool for assessing endometrial receptivity when undergoing assisted reproductive treatment.
1987 Ph.D. Reproductive Endocrinology/Physiology, University of Wisconsin-Madison, Madison, WI.
1982 M.S. Anatomy, Purdue University, West Lafayette, IN.
1978 B.S. Zoology & Cell Biology, School of Science, Purdue University, West Lafayette, IN.
1973-75 Philosophy and Literature, Transylvania University, Lexington, KY.
PUBLICATIONS in PEER-REVIEWED JOURNALS
- Clancy, K.B.H., A.R. Baerwald and R.A. Pierson. 2016. Cycle-phase Dependent Associations between CRP, Leptin and Reproductive Hormones in an Urban, Canadian Sample. American Journal of Physical Anthropology (wPub Ahead of Print: ajpa22976).
- Yapura, M.J., R.J. Mapletoft, R.A. Pierson, J. Singh and G.P. Adams. 2016. Synchronization of Ovulation in Cattle with an Aromatase Inhibitor-based Protocol. Theriogenology 85:1382-1389.
- Jackowski, S.A., A.D.G. Baxter-Jones, A.J. McLardy, R.A. Pierson and C.D. Rodgers. 2015. The associations of exposure to combined hormonal contraceptive use on bone mineral content and areal bone mineral density accrual from adolescence to young adulthood: A longitudinal study. Bone Reports http://www.sciencedirect.com/science/article/pii/S2352187215300061 (In Press).
- J. Yapura, I. Badea, G. Zamberlam, C. Price, R. Mapletoft, R.A. Pierson, J. Singh, G.P. Adams. 2015. Formulation and testing of a non-steroidal aromatase inhibitor intravaginal device for the control of ovarian function in cattle. Animal Reproduction Science 156:91-102.
- Christ, J.P., H. VandenBrink, E.D. Brooks, R.A.Pierson, D.R. Chizen and M.E. Lujan. 2015. Ultrasonographic Features of Polycystic Ovaries Relate to the Degree of Reproductive and Metabolic Disturbance in Polycystic Ovary Syndrome (PCOS). Fertility and Sterility 103(3):787-794.
- Pierson, R.A., O.A. Olatunbosun, D.R. Chizen, H. Saunders, E. Loumaye and B. DeMoustier. 2014. Recombinant Human Luteinizing Hormone to Trigger Ovulation: A Prospective, Randomized, Phase II Dose-Finding Study. Journal of Reproductive Medicine 59(7-8):355-366.
- Williamson, L.E.A., K.L. Lawson, P.J. Downe and R.A. Pierson. 2014. Informed Reproductive Decision-Making: The Impact of Providing Fertility Information on Fertility Knowledge and Intentions to Delay Childbearing. Journal of Obstetrics and Gynecology Canada 36(5):400-405.
- Clark, N.M., A.J. Podolski, E.D. Brooks, D.R. Chizen, R.A. Pierson, D.C. Lehotay and M.E. Lujan. Prevalence of Polycystic Ovary Syndrome Phenotypes Using Updated Criteria for Polycystic Ovarian Morphology: An Assessment of Over 100 Consecutive Women Self-reporting Features of Polycystic Ovary Syndrome. Reproductive Sciences 21(8):1034-1043.
- Yapura, M.J., R.J. Mapletoft, R.A. Pierson, J. Singh and G.P. Adams. 2014. Effects of Vehicle and Route of Administration of Letrozole on Ovarian Function in a Bovine Model. Reproduction, Fertility and Development 26:1198-1205.
- Pfiefer, L.F.M., G.P. Adams, R.A. Pierson and J. Singh. 2014. Ultrasound Biomicroscopy: A Non-Invasive Approach for In Vivo Evaluation of Oocytes and Small Antral Follicles in Mammals. Reproduction, Fertility and Development 26(1): 48-54. DOI: 10.1071/RD13305.
- Christ, J.P, A.D. Willis, E.D. Brooks, H. Vanden Brink, B.Y. Jarrett, R.A. Pierson, D.R. Chizen and M.E. Lujan. 2013. Follicle Number, and Not Assessments of the Ovarian Stroma, Represents the Best Ultrasonographic Marker of Polycystic Ovary Syndrome. Fertility and Sterility 101(1):280-288.
- Yapura, M.J., R.J. Mapletoft, R.A. Pierson, J. Singh and G.P. Adams. 2013. Aromatase Inhibitor Treatment with an Intravaginal Device and its Effect on Pre-ovulatory Ovarian Follicles in a Bovine Model. Reproductive Biology and Endocrinology. 11:97-104. DOI: 10.1186/10.1186/1477-7827-11-97
- Clancy, K.B.H., A.R. Baerwald and R.A. Pierson. 2013. C-Reactive Protein (CRP) in Relation to Follicle Wave Dynamics during the Spontaneous Menstrual Cycle. Public Library of Science One (PLoS 1) 8(5): e64807. doi:10.1371/journal.pone.0064807.
- Lujan, M.E., B.Y. Jarrett, E.D. Brooks, J.K. Reines, A.K. Peppin, N. Muhn, E. Haider, R. A. Pierson and D.R. Chizen. 2013. Updated Ultrasound Criteria for Polycystic Ovary Syndrome: Reliable Thresholds for Elevated Follicle Population and Ovarian Volume. Human Reproduction 28(5):1361-1268.
- Dong, M., M.G. Eramian, S. Ludwig and R.A. Pierson. 2013. Automatic Detection and Segmentation of Bovine Corpora Lutea in Ultrasonographic Ovarian Images using Genetic Programming and Rotation Invariant Local Binary Patterns. Medical and Biological Engineering and Computing 51:405-416.
- Chilibeck, P.D., H. Vatanparast, R.A. Pierson, A. Case, O. Olatunbosun, S.J. Whiting, H.J. Biem, P. Pahwa and T.J. Beck. 2013. Effect of Exercise Training Combined with Isoflavone Supplementation on Bone and Lipids in Post-Menopausal Women: A Randomized Clinical Trial. Journal of Bone and Mineral Research 28(4):780-793.
- Ratto, M.H., Y.A. Leduc, X.P. Valderrama, K.E.van Straaten, L.T.J. Delbaere, R.A. Pierson and G.P. Adams. 2012. The Nerve of Ovulation-Inducing Factor in Semen. Proceedings of the National Academy of Sciences (PNAS) 109(37):15042-15047.
- Pfeifer, L.F.M., L.G.B. Siqueira, G.P. Adams, R.A. Pierson and J. Singh. 2012. In Vivo Imaging of Cumulus-Oocyte-Complexes and Small Ovarian Follicles in Cattle using Ultrasound Biomicroscopy. Animal Reproduction Science 131:88-94.
- Yapura, J., R.J. Mapletoft, J. Singh, R.A. Pierson, J. Naile, J.P. Geisy, H. Chang, E. Higley, M. Hecker and G.P. Adams. 2012. Effects of a Non-steroidal Aromatase Inhibitor on Ovarian Function in Cattle. Reproduction, Fertility and Development 24:631-640.
- Smith, G.N., H. McNamara, P. Bessette, V.M. Allen, S. Ross, J. Schultz, R.A. Pierson, B. Nadeau for the APOG Research Committee. 2011. Resident Research Training Objectives and Requirements of the Association of Academic Professionals in Obstetrics and Gynecology (APOG). Journal of Obstetrics and Gynecology Canada 22(10):1044-1046.
- Bowen, R., A. Bowen, M. Baetz, J. Wagner and R. A. Pierson 2011. Mood Instability in Women with Premenstrual Syndrome. Journal of Obstetrics and Gynecology Canada 33(9):927-934.
- Yapura, J., R.J. Mapletoft, R.A. Pierson, J. Singh, J. Naile, J.P. Geisy and G.P. Adams. 2011. A Bovine Model for Examining the Effects of Aromatase Inhibitor on Ovarian Function in Women. Fertility and Sterility 96(2):434-441.
- Ratto, M.H., L.T.J. Delaere, Y.A. Leduc, R.A. Pierson and G.P. Adams. 2011. Isolation and Purification of Ovulation Inducing Factor (OIF) in Seminal Plasma of Llamas. Reproductive Biology and Endocrinology 9:24-38.
- Lujan, M.E., A. Podolski, D.R. Chizen, D. Lehotay and R.A. Pierson. 2010. Digit Ratios by Computer-Assisted Analysis Confirm Lack of Anatomical Evidence of Prenatal Androgen Exposure in Clinical Phenotypes of Polycystic Ovary Syndrome. Reproductive Biology and Endocrinology 8:15-22.
- Lujan, M.E., A.L. Kepley, D.R. Chizen, D.C. Lehotay and R.A. Pierson. 2010. Development of Morphologically Dominant Follicles is associated with Fewer Metabolic Disturbances in Amenorrheic Women with Polycystic Ovary Syndrome: A Pilot Study. Journal of Ultrasound in Obstetrics and Gynecology 36:759-766.
- Lujan, M.E., E.D. Brooks, A.L. Kepley, D.R. Chizen, R.A. Pierson and A.K. Peppin. 2010. Grid Analysis Improves Reliability in Follicle Counts Made by Ultrasonography in Women with Polycystic Ovary Syndrome. Journal of Ultrasound in Medicine and Biology 36(5):712-718.
- Colwell, K., M.E. Lujan, K.L. Lawson, R.A. Pierson and D.R. Chizen. 2010. Women’s Perceptions of Polycystic Ovary Syndrome (PCOS) following Participation in a Clinical Research Study: Implications for Knowledge, Feelings and Daily Health Practices. Journal of Obstetrics and Gynecology Canada 32(5):453-459.
- Pierson, R.A. and R.A. Stephanson. 2010. Imagining Reproduction in Science and History. Journal of Medical Humanities 31(1):1-9.
- Lujan, M.E., T.G. Bloski, D.R. Chizen, D.C. Lehotay and R.A. Pierson. 2010. Digit Ratios Do Not Serve as Anatomical Evidence of Prenatal Androgen Exposure in Clinical Phenotypes of Polycystic Ovary Syndrome. Human Reproduction 25:204-211.
- Lujan, M.E., D.R. Chizen, A.K. Peppin, A. Dhir and R.A.Pierson. 2009. Assessment of Ultrasonographic Features of Polycystic Ovaries is Associated with Modest Levels of Inter-Observer Agreement. Journal of Ovarian Research. 2:6-15.
- Mircea, C.N., M.E. Lujan, R.S. Jaiswal, J. Singh, G.P. Adams and R.A.Pierson. 2009. Ovarian Imaging in the Mouse using Ultrasound Biomicroscopy (UBM): A Validation Study. Reproduction, Fertility and Development. 21(4):365-370.
- Allaway, H.C., T.G. Bloski, R.A.Pierson and M.E. Lujan. 2009. Digit Ratios (2D:4D) Determined by Computer-Assisted Analysis are More Reliable than Those Using Physical Measurements, Photocopies, and Printed Scans. American Journal of Human Biology 21:365-370.
- Baerwald, A.R., R.A. Walker and R.A. Pierson. 2008. Growth and Regression Rates of Ovarian Follicles during Natural Menstrual Cycles, Oral Contraception Cycles and Ovarian Stimulation Cycles. Fertility and Sterility 91(2): 440-449.
- Giede, K.C., T.W. Yen, R. Chibbar and R.A. Pierson. 2008. Significance of Concurrent Endometrial Cancer in Women with a Pre-Operative Diagnosis of Atypical Endometrial Hyperplasia. Journal of Obstetrics and Gynecology Canada 30:896-981.
- Russnell, B.J., R.A. Pierson, J. Singh, G.P. Adams and M.G. Eramian. 2008. Level Set Segmentation of Bovine Corpora Lutea in Ovarian Ultrasound Images. Reproductive Biology and Endocrinology 6:33-49.
- Lujan, M.E., D.R. Chizen, A.K. Peppin, D.A. Leswick, S. Kreigler, T.G. Bloski and R.A. Pierson. 2008. Improving Inter-Observer Variability in the Identification and Quantification of Ultrasonographic Features of Polycystic Ovaries. Reproductive Biology and Endocrinology 6:30-41.
- Lo, S.T., P. Ramsay, R.A. Pierson, F. Manconi, M.G. Munro and I.S. Fraser. 2008. Endometrial Thickness Measured by Ultrasonography in Women with Uterine Outlet Obstruction due to Intrauterine or Upper Cervical Adhesions. Human Reproduction 23(2):306-309.
- Eramian, M.A., G.P. Adams, and R.A. Pierson. 2007. Enhancing Ultrasound Texture Differences for Developing an In Vivo “Virtual Histology” Approach to Bovine Ovarian Imaging. Reproduction, Fertility and Development 19:910-924.
- Lawson, K.L. and R.A. Pierson. 2007. Maternal Decisions following Prenatal Diagnosis: Rational Choices or Sensible Decisions? Journal of Obstetrics and Gynecology Canada 29: 240-246.
- Malhi, P.S., G.P. Adams, R.A. Pierson and J. Singh. 2006. Bovine Model of Reproductive Aging: Response to Ovarian Synchronization and Superstimulation. Theriogenology 66(5):1257-1266.
- Bian, N., M.G. Eramian and R.A.Pierson. 2006. Evaluation of Texture Features for Analysis of Ovarian Follicular Development. Medical Image Computation and Computer Assisted Intervention. 9(2):93-100.
- Sarty, G.E., E.J. Kendall, G.P. Adams and R.A. Pierson. 2006. Nuclear Magnetic Resonance Spectroscopy of Bovine Ovarian Follicular Fluid through the Estrous Cycle. Reproduction, Fertility and Development 18:559-571.
- Baerwald, A.R., O.A. Olatunbosun and R.A. Pierson. 2006. Effects of Administration of Oral Contraceptives at Defined Stages of Ovarian Follicular Development. Fertility and Sterility 86(1):27-35.
- Bergfelt, D.R., R.A. Pierson and O.J. Ginther. 2006. Luteal Regression and Follicle Development Following Prostaglandin-F2α Treatment Three Days After Ovulation in Mares. Theriogenology 65:1605-1619.
- Birtch, R.L, O.A. Olatunbosun and R.A. Pierson. 2006. Ovarian Follicular Dynamics during Conventional versus Continuous Oral Contraceptive Use. Contraception 73:235-243.
- Sarty, G.E. and R.A. Pierson. 2005. Mathematical Modelling of Ovarian Follicle Growth for the Prediction of Ovarian Response to Superstimulation. Mathematical Biosciences 198:80-96.
- Ginther, O.J., M.A. Beg, E.L. Gastal, M.O. Gastal, A.R. Baerwald and R.A. Pierson. 2005. Systemic Concentrations of Hormones during Development of Follicular Waves in Mares and Women: A Comparative Study. Reproduction 130:379-388.
- Birtch, R.L., A.R. Baerwald, O.A. Olatunbosun and R.A. Pierson. 2005. Ultrasound Image Attributes of Human Dominant Ovarian Follicles During Natural and Oral Contraceptive Cycles. Reproductive Biology and Endocrinology 3:12 (1-8).
- Baerwald, A.R., G.P. Adams and R.A. Pierson. 2005. Form and Function of the Corpus Luteum during the Human Menstrual Cycle. Journal of Ultrasound in Obstetrics and Gynecology 25:498-507.
- Sarty, G.E., A.R. Baerwald, J. Lowey and R.A. Pierson. 2005. Externally Placed Versus Intravaginally Positioned Radio Frequency Coils for Quantitative Spin-Spin Relaxometry of Ovarian Follicular Fluid. Canadian Association of Radiologists Journal 56:40-47.
- Ginther, O.J., E.L. Gastal, M.O. Gastal, D.R. Bergfelt, A.R. Baerwald and R.A. Pierson. 2004. Comparative Study of the Dynamics of Follicular Waves in Mares and Women. Biology of Reproduction 71(4):1195-1201.
- Baerwald, A.R., O.A. Olatunbosun and R.A. Pierson. 2004. Ovarian Follicular Waves are initiated during the Hormone Free Interval in Women using Oral Contraception. Contraception 70(5):371-377.
- Baerwald, A.R and R.A. Pierson. 2004. Endometrial Dynamics in Association with Ovarian Follicular Waves during the Menstrual Cycle. Journal of Ultrasound in Obstetrics and Gynecology 24(4):453-460.
- Sarty, G.E., E.J. Kendall, J. Loewy, A. Dihr, O.A. Olatunbosun, and R.A. Pierson. 2004. Magnetic Resonance Diffusion Imaging of Ovarian Masses: A First Experience. Magnetic Resonance Imaging Methods for the Study of Ovarian Structure and Function (MAG*MA) 16:182-193.
- Delbaere, A., G. Smits, O.A. Olatunbosun, R.A. Pierson, G. Vassart and S. Costagliola. 2004. New Insights into the Pathophysiology of the Ovarian Hyperstimulation Syndrome. What Makes the Difference Between Spontaneous and Iatrogenic Syndrome? Human Reproduction 19:486-489.
- Honaramooz, A., J.P. Adavindakshan, R.K. Chandiola, A.P. Beard, P.M. Bartlewski, R.A. Pierson and N.C. Rawlings. 2004. Ultrasonographic Evaluation of the Prepubertal Development of the Reproductive Tract in Beef Heifers. Animal Reproduction Science 80:15-29.
- Baerwald, A.R., G.P. Adams, and R.A. Pierson. 2003. Characterization of Ovarian Follicular Wave Dynamics in Women. Biology of Reproduction.69:1023-1031.
- Smits, G., O.A. Olatunbosun, A. Delbaere, R.A. Pierson, G. Vassart, and S. Costagliola. 2003. Recurrent Spontaneous Ovarian Hyperstimulation Syndrome Caused by a Mutant Follitropin Receptor Constitutively Active and Hypersensitive to Human Chorionic Gonadotropin. New England Journal of Medicine 349(8):760-766.
- Duggavathi, R., P.M. Bartlewski, R.A. Pierson and N. C. Rawlings. 2003. Luteogenesis in Cyclic Ewes: Echotextural, Histomorphologic and Functional Correlates. Biology of Reproduction 69(2):634-639.
- Pierson, R.A. 2003. Imaging the Endometrium: Are There Predictors of Endometrial Receptivity? Journal of Obstetrics and Gynecology Canada 25:360-368.
- Singh, J., G.P. Adams and R.A. Pierson, 2003. Promise of New Imaging Technologies for Visualizing Ovarian Function. Animal Reproduction Science 78:371-399.
- Pierson, R.A., D.F. Archer, M. Moreau, G. Shangold, A.C. Fisher, and G.W. Creasy. 2003. Ortho Evra™/Evra™ versus Oral Contraceptives: Follicular Development and Ovulation in Normal Cycles and After an Intentional Dosing Error. Fertility and Sterility 80(1):34-42.
- Baerwald, A.R., G.P. Adams and R.A. Pierson. 2003. A New Model for Folliculogenesis during the Menstrual Cycle in Women. Fertility and Sterility 80(1):116-122.
- Olatunbosun, O.A., R.W. Turnell, and R.A. Pierson. 2003. Transvaginal Sonography and Fiberoptic Illumination of Uterine Vessels for Abdominal Cervico-Isthmic Cerclage. Obstetrics and Gynecology 102:1131-1133.
- Hilton, J.L., A.R. Baerwald(Hess), G.E. Sarty, G.P. Adams, and R.A. Pierson. 2003. Magnetic Resonance Imaging Attributes of the Corpus Luteum during Development and Regression. Anatomical Record 272A:454-459.
- Vasenna, R., R.J. Mapletoft, R.A. Pierson, J. Singh and G.P. Adams. 2003. Ultrasound Image Characteristics of Ovarian Follicles in Relation to Oocyte Competence and Follicular Status in Cattle. Animal Reproduction Science 76:25-41.
- Chizen, D.R. and R.A. Pierson. 2010. Clinical Applications of Ultrasonography in Infertility Assessment and Therapy. In GLOBAL LIBRARY OF WOMEN’S MEDICINE. J.C. Sciarra (Editor-in-Chief). http://www.glowm.com/. ISSN: 1756-2228 2008 DOI:10.3843/GLOWM.10326 [pp 1-85].
- Pierson, R.A. 2008. Ultrasonography in Infertility. In P.W. Callen (Editor), ULTRASONOGRAPHY IN OBSTETRICS AND GYNECOLOGY. Fifth Edition. ISBN 1-416032649. WB Saunders, Philadelphia, PA. pp 986-1019.
- Bain, N., R.A. Pierson and M.A. Eramian. 2006. Evaluation of Texture Features for Analysis of Ovarian Follicular Development. In, LECTURE NOTES IN COMPUTER SCIENCE SERIES, MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION–MICCAI-2006. ISBN: 3540447075. Volume 4191/2006, Springer Berlin pp 93-100.
- Pierson, R.A. 2006. Ultrasound in IVF. In D.K. Gardner (Editor), IN VITRO FERTILIZATION: A PRACTICAL APPROACH, Third Edition. ISBN: 0-849333350. CRC Press, New York, NY. pp 91-115.
- Pierson, R. A., and Olufemi A. Olatunbosun. 2004. Transvaginal Ultrasonography and the Evaluation of Female Infertility. In J.J. Sciarra (Editor), GYNECOLOGY AND OBSTETRICS: 2004 ISBN: 9-780781752541. Volume 5; Chapter 55 pp 1-12.
- Pierson, R.A. 2001. New Developments in Ovarian Stimulation and Ultrasonography. In ART AND THE HUMAN BLASTOCYST. D.K. Gardner and M. Lane (Editors). ISBN 0-387952454. Springer-Verlag, New York, NY 29-37.
- Pierson, R.A. 2000. Imaging Technology in Assisted Reproduction. In ASSISTED REPRODUCTION AND NUCLEAR TRANSFER IN MAMMALS. D. Wolf and M. Zelinski-Wooten (Editors). ISBN 0-89603663-4. Humana Press, Totowa, NJ pp 95-122.
- Pierson, R.A. 1999. Three-Dimensional Ultrasonography of the Embryo and Fetus. In TEXTBOOK OF FETAL ULTRASOUND. R. Jaffe and T.H. Bui (Editors). ISBN: 1850700176. Parthenon Publishing Group, NY pp 317-326.