Karen Klein, M.D.


3020 Children's Way
MC 5103
San Diego, CA 92123




Rady Children's Specialists of San Diego

Medical Group / IPA

Rady Children's Specialists

Other Languages


Medical School

Pennsylvania State University


Hershey Medical Center


Hershey Medical Center

Board Certifications

Pediatric Endocrinology, Pediatrics




Dr. Karen Klein is a board-certified pediatric endocrinologist at Rady Children's Hospital-San Diego and an associate clinical professor of pediatrics at UC San Diego School of Medicine.

Earning her medical degree at the Pennsylvania State College of Medicine and completing a residency in pediatrics at the same institution, Dr. Klein went on to complete a fellowship in pediatric endocrinology at the National Institute of Child Health and Development, National Institutes of Health in Bethesda, Md. During her training, she developed a novel laboratory method for measuring very low levels of estrogen, which she has used extensively since that time in clinical research.

Dr. Klein's clinical and research interests include pubertal development and growth, and the treatment of precocious puberty. She has lectured on these topics locally, nationally and internationally, and her work has been published in peer-reviewed journals and textbooks. She also enjoys teaching and mentoring students, residents and fellows.

When not working, Dr. Klein is very involved in her church, community and local high school. She enjoys watching her son play lacrosse and soccer, and watching her daughter play soccer and run track.


Ultrasensitive estrogen levels at 7 years of age predict earlier thelarche: evidence from girls of the growth and obesity Chilean cohort.
Pereira A, Corvalán C, Uauy R, Klein KO, Mericq V

Randomized clinical trial evaluating metformin versus oral contraceptive pills in the treatment of adolescents with polycystic ovarian syndrome.
Al-Zubeidi H, Klein KO

A pediatrician's guide to central precocious puberty.
Kletter GB, Klein KO, Wong YY

Importance of leuprolide acetate variable dosing for precocious puberty: a range of acceptable suppression.
Cohen D, Janfaza M, Klein KO

Sequential comparisons of one-month and three-month depot leuprolide regimens in central precocious puberty.
Badaru A, Wilson DM, Bachrach LK, Fechner P, Gandrud LM, Durham E, Wintergerst K, Chi C, Klein KO, Neely EK

Virilization of young children after topical androgen use by their parents.
Kunz GJ, Klein KO, Clemons RD, Gottschalk ME, Jones KL

Treatment of urogenital atrophy with low-dose estradiol: preliminary results.
Santen RJ, Pinkerton JV, Conaway M, Ropka M, Wisniewski L, Demers L, Klein KO

See the full listing of this physician's publications on PubMed, a service of the National Library of Medicine.

PubMed is a third-party website and not affiliated with Rady Children's Hospital-San Diego.