Muriel Betty McIlrath was a gynaecologist in Sydney, New South Wales. She was born on 14 July 1907 in New South Wales. Her father, Martin McIlrath, had emigrated from Ireland to Australia in 1889, set up a grocery company with his brother, and became a successful businessman, grazier and philanthropist. He was posthumously knighted. Her mother was Ada Maitland McIlrath née Eldridge. McIlrath studied medicine at the University of Sydney and qualified with an MB BS in 1930. She went to the UK for further training, where she was a house surgeon at St Mary’s Hospital, Manchester and later a resident obstetrical officer at the Withington Hospital. She gained her fellowship of the Royal College of Surgeons of England in 1935 and her membership of what was then the College of Obstetricians and Gynaecologists in 1936. Whilst she was training in the UK, she wrote several papers, including ‘Bilateral tubal pregnancy’ (*Br Med J*. 1937 May 22;1[3985]:1065-6) and ‘Fibroma of the ovary: a clinical study’ (*BJOG* Vol 44 (6) December 1937 1102-8). She returned to New South Wales, where she became an honorary assistant gynaecological surgeon at the Royal Prince Alfred Hospital, Sydney. She also set up in practice in Macquarie Street. In the forties she wrote a series of papers for the *Medical Journal of Australia* and the *Journal of obstetrics and gynaecology of the British Empire*, including ‘Maldevelopment of the female genital tract’ (*Med J Aust*. 1946 Nov 16;2[20]), ‘Primary carcinoma of the vagina; a brief review of the literature and reports of four cases’ (*Med J Aust*. 1947 Aug 23;2[8]:231-4) and ‘Studies in the biology of the cervix and its relation to puerperal infections’ (*J Obstet Gynaecol Br Emp*. 1947 Dec;54[6]:746-7). In l948 she spent five months in England, America, Sweden and France investigating the latest techniques in gynaecology. In 1957, aged 49, she married Charles Lawrence Regan, an Australian lawyer, in London. She spent many years living in Canberra. Predeceased by her husband in 1970, she died on 26 April 1982 at the age of 74.