Yin May

Back in Rangoon, Yin May started as the Assistant Medical Superintendent of Lady Dufferin Maternity Hospital in 1930. As the deputy head of a major hospital, she had joined the upper echelons of the tiny colonial era medical community made up mainly of foreign-born physicians and specialists that existed primarily in Rangoon (Yangon). (Her two superiors during her first stay at the hospital (1930–1936) were British IMS officers: Lt. Col. S.T. Crump (1930–1931) and Lt. Col. M.L. Treston (1931–1936).)

Yin May was instrumental in the expansion of modern obstetrics and gynecology (OG/OBGYN) practices in Burma; she was the first person to perform the Caesarian section in the country. She started an OG program at Rangoon Medical College that finally yielded the country's first ever MBBS graduates specializing in OG, and founded the first OG training school for midwives that taught primarily in Burmese in 1937. All the while, she contributed to the field. In 1937, she published her most famous research paper in The Indian Medical Gazette on amoebic vaginitis, which was subsequently named May's disease.

Yin May founded and ran the country's main maternity hospital during World War II (1942–1945). It was out of sheer necessity. The country had been without its main maternity hospital since 25 December 1941 when Japanese aerial bombing destroyed Dufferin Hospital. Patients from Dufferin were moved to Rangoon General Hospital but the Imperial Japanese Army seized the general hospital for its exclusive use in March 1942, leaving the non-Japanese without a hospital. Most of its tiny colonial era medical staff had also fled. Indeed, she herself fled with her husband Min Sein and their young son to Upper Burma in early 1942. But she somehow got separated from her family in Upper Burma, and returned to Rangoon c. mid 1942 alone, and pregnant. She then joined BIA Hospital, the makeshift hospital founded by Dr. Ba Than, as the head of the Maternity Unit.

It would prove to be her biggest challenge yet. In the beginning, she had no staff with any OG experience; she was assigned just one novice physician Kyee Paw and a few nurses. According to Myint Swe, a pregnant Yin May, despite getting tired easily, worked all hours at the hospital; she even went back to work the night after she had given birth herself to perform a complicated surgery to save a mother's life. In late 1942, she was able to establish a maternity hospital in Tamwe Township. Dr. Kyee Paw, who would later become a highly accomplished surgeon and professor in his own right, joined as her deputy. The maternity hospital proved a lifeline to many would-be mothers, and became a training ground for a new generation of several young physicians and nurses. She, along with Drs. Ba Than and S. Sen, was a co-founder of the wartime medical and nursing schools. The trio oversaw the programs, and graded exam papers.

After the war, she continued her roles as the foremost OG practitioner and educator in the country. She served as the head of the reconstructed Dufferin Hospital from 1946 to 1959, and also as the head of the Department of Obstetrics and Gynecology of the Faculty of Medicine of Rangoon University from 1947 to 1959. Between 1946 and 1948, she as the head (Medical Superintendent) of Dufferin also became a Lt. Col. in Burma Medical Service in the colonial administration called Civil Affairs Service, Burma (CAS-B). She was responsible for getting Dufferin Hospital to be recognized as a teaching hospital by the Royal College of Obstetricians and Gynaecologists in 1957. Having a local RCOG recognized hospital made it much easier for Burmese OGs to pursue FRCOG fellowships. Through the process, Yin May too became an FRCOG in 1957. It was her third fellowship; she became an FRCP from Royal College of Physicians, Edinburgh in 1954. She was the first Burmese to achieve a fellowship in three different disciplines, and is recognized as one of the pioneers of modern medicine in Myanmar.

Prof. Yin May retired in 1959 but remained active. She was a member of the executive committee of Burma Research Society. She died on 29 September 1978 in Rangoon. Her husband Min Sein died six weeks later on 9 November 1978. For her services to the country, she was awarded the title of Thiri Pyanchi in 1949.