Dr. Thornton is a double-Board Certified specialist in obstetrics, gynecology and maternal-fetal medicine. She has risen to the academic rank of Professor of Clinical Obstetrics and Gynecology. She is a member of the Association of Women Surgeons, a life member of The New York Academy of Medicine, and is a Fellow of the American College of Obstetricians and Gynecologists and the American College of Surgeons.

Her biography is presently in  Who's Who in America and Who's Who in the World. She is listed in The Best Doctors -- New York Metro Area. She was listed in New York Magazine as one of the Top Ten Maternal-Fetal Medicine Specialists in New York City.

Doctor Thornton was the first black woman in the United States to be Board-certified in High-Risk obstetrics and to be accepted into The New York Obstetrical Society.

Dr. Thornton is the national best-selling author of the Pulitzer prize-nominated book entitled, The Ditchdigger's Daughters: A Black Family's Astonishing Success Story published in 1995, with over 300,000 copies in print. This family biography (co-authored with Jo Coudert) is a tribute to her parents and was condensed in The Reader's Digest, adapted into a World Premiere Movie and nominated for the Peabody Award and the Cable ACE Award for Best Picture.

In 1996, the American Library Association named it as one of the Best Books for Young Adults and Doctor Thornton was given the "Excellence in Literature" Award by the New Jersey Education Association. She has authored two other books;a medical text entitled, Primary Care for the Obstetrician and Gynecologist and Woman to Woman: Leading Gynecologist Tells You All You Need Know abt your Baby your Health.