John Williams, MD

Director, Reproductive Genetics Service

Professor, Obstetrics and Gynecology

Mark Goodson Building
444 S. San Vicente Blvd.
Suite 1001
Los Angeles, CA 90048





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Marina Del Rey Hospital
4650 Lincoln Blvd.
Suite 102
Marina del Rey, CA 90292

John Williams, MD

Director, Reproductive Genetics Service

Professor, Obstetrics and Gynecology

  • Medical Genetics
  • OB/GYN-Maternal Fetal Medicine


Chorionic Villus Sampling (CVS)

Genetic Testing (Prenatal Diagnosis)

High Risk Pregnancy

John Williams, MD, is the director of Reproductive Genetics and a full-time faculty member in the Division of Maternal-Fetal Medicine and the Department of Obstetrics and Gynecology. He is also a professor of Obstetrics and Gynecology. For 30 years, his research has been in the area of first-trimester prenatal diagnosis and screening. Since rejoining the full-time faculty at Cedars-Sinai nearly 20 years ago, Dr. Williams has developed one of the most comprehensive first-trimester prenatal diagnosis programs in the United States. As a pioneer in chorionic villus sampling (CVS), he has performed more than 31,000 of these procedures to date. During the 2015-16 academic year, Dr. Williams performed 546 CVS procedures. Most recently, his research has focused on identification of potential markers of risk for subsequent development of pregnancy complications. Currently, he is building a tissue repository of blood, urine, saliva and chorionic villus samples in patients undergoing CVS. His team has enrolled over 2,300 patients in the repository. Dr. Williams is conducting a study to investigate the relationship between placental genes, vascular growth factors and various markers in the first and early second trimesters, and risk for adverse perinatal outcome, including maternal hypertensive disorders, fetal growth abnormalities, preterm labor and premature rupture of membranes.

  • Medical School: UCLA, 1978
  • Internship: Harbor-UCLA Medical Center, 1979
  • Residency: Harbor-UCLA Medical Center, 1982
  • Fellowship: Harbor-UCLA Medical Center, 1985
  • Los Angeles Magazine Top Doctors (as selected by their peers), 2017
  • Southern California Super Doctors, 2014-15
  • Council on Resident Education in Obstetrics and Gynecology Award for Excellence in Teaching, Department of Obstetrics and Gynecology, 2012
  • Golden Apple Award for Excellence in Teaching, Cedars-Sinai Department of Obstetrics and Gynecology, 2010
  • Outstanding and Distinguished Service as Director for Maternal Fetal Medicine, Cedars-Sinai Department of Obstetrics and Gynecology, 2005-07
  • March of Dimes Healthy Babies Healthy Future Award, 2002
  • Outstanding Service on the American Academy of Pediatrics Committee on Genetics, 1999-2001
  • Outstanding Service on the American College Obstetricians and Gynecologists Committee on Genetics, 1997-2001

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  • Adeniji B, Williams J 3rd, Solt I, Morales C, Alanakian A, Rotmensch S. Clinical trial of muliplanar real-time 4- versus 2-dimensional sonographic guidance for transcervical chorionic villus sampling. J Ultrasound Med. 2011;30(3):309-312.
  • Norton ME, Brar H, Weiss J, Karimi A, Laurent LC, Caughey AB, Rodriguez MH, Williams J 3rd, Mitchell ME, Adair CD, et al. Non-Inasive Chromosomal Evaluation (NICE) Study: results of a multicenter prospective cohort study for detection of fetal trisomy 21 and trisomy 18. Am J Obstet Gynecol. 2012;207(2):137.e1-8.
  • Lambert-Messerlian G, Kloza EM, Williams J 3rd, Loucky J, O'Brien B, Wilkins-Haug L, Mahoney MJ, De Biasio P, Borrell A, Ehrich M, et al. Maternal plasma DNA testing for aneuploidy in pregnancies achieved by assisted reproductive technologies. Genet Med. 2014;16(5):419-422.
  • Lau GW, Feldman DS, Morales CM, Smith D, Edwards R, Williams J 3rd. First-trimester aneuploidy screening: is there a maternal age at which it loses its effectiveness? J Reprod Med. 2014;59(9-10):443-447.
  • Williams J 3rd, Rad S, Beauchamp S, Ratousi D, Subramaniam V, Farivar S, Pisarska MD. Utilization of noninvasive prenatal testing: Impact on referrals for diagnostic testing. Am J Obstet Gynecol. 2015;213(1):102.e1-6.
  • Pisarska MD, Akhlaghpour M, Lee B, Barlow GM, Xu N, Wang ET, Mackey AJ, Farber CR, Rich SS, Rotter JI, Chen YI, Goodarzi MO, Guller S, Williams J 3rd. Optimization of techniques for multiple platform testing in small, precious samples such as human chorionic villus sampling. Prenat Diagn. 2016;36(11):1061-1070.

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