Leona Ruth Hurwitz Zacharias (1907 – 1990) was an American biologist and medical researcher whose career spanned several prestigious institutions and diverse fields.

[2] Zacharias also made substantial contributions to the understanding of human maturation, as measured by, the onset of menstruation and its variability in adolescent girls.

[2][4] Zacharias’s doctoral research explored cellular proliferation in grafted segments of the embryonic spinal cord and was published in the "Journal of Experimental Zoology.

The scarring pulls on the retina, which can detach from the back of the eye, leading to impaired vision and, in severe cases, complete and irreversible blindness.

At least as perplexing, RLF was occurring almost entirely in affluent countries with advanced medical technologies; it was all but unknown in poorer nations lacking sophisticated hospital care for premature babies.

(Parallel studies, based first in Washington, D.C. and then in Baltimore, under Dr. Arnall Patz, would come to similar and compatible conclusions about the cause of premature infants’ postnatal blindness.

[2] This paper, credited solely to Terry, tested various hypotheses about the disease such as birth order, sex of the baby, deficiencies in iron or vitamin A, and oxygen, which was routinely given to premature infants for their developing lungs.

[25][18][26] This discovery was groundbreaking, revealing that the oxygen therapy used to support premature infants’ developing lungs at the same time disrupted blood vessel growth in the retina, leading to retinal detachment and blindness.

[27] Her research provided crucial insights into the genetic and environmental influences on menarche, and challenged prevailing notions about sexual maturation of girls.

[2][3] Her husband, Jerrold R. Zacharias, was a nuclear physicist who developed the first atomic clock and served on the President’s Science Advisory Committee.