Thomas Young (ca. 1725/6-1783) was the son of Janet Ross and George Young, also a surgeon, but little is known of his early life and education. He is known to have become a member of the surgeons' guild in Edinburgh on 8 May 1751 without having to sit the examination owing to the fact that he was the son of an existing member. Presumably, he would have served an apprenticeship prior to this, and may even have spent time abroad, as was not uncommon at the time. He became Deacon of the Incorporation of Surgeons in 1756, but later decided upon joining the Royal College of Physicians instead and so took his medical degree in 1761. For this he submitted a dissertation on the diseases arising from the use of milk, which was published some years later in 1776 as Dissertation Medica, de natura et usu lactis in diversis animalibus.
Young is known to have been practising surgery and lecturing privately in midwifery by 1750 and in that year he published a syllabus of lectures, 22 in total. A price list for receiving his instruction shows that he was also teaching women who had 'the privilege of attending the labours'. On 9 February 1756 he was officially appointed to the vacant post of Professor of Midwifery at the University of Edinburgh. This was the UK's first professorship in midwifery and whilst Young was the third person to hold the position, after Joseph Gibson and Robert Smith, he was nevertheless the first to actually deliver a course of lectures in obstetrics and midwifery. Prior to this appointment Young had been working and teaching at the Edinburgh Royal Infirmary, serving as an attending surgeon since 1751, and it is likely that his obvious professional activity made him a good candidate for the role in contrast to his predecessors who did not undertake any active teaching.
In 1755, just a few months before he obtained the professorship he requested that one ward in the Infirmary be put aside for lying-in cases for the teaching of students and midwives. His request was soon met and this became the first lying-in ward in Scotland and seemed to command a certain degree of autonomy within the Infirmary. Midwifery was not placed amongst the core medical subjects and made compulsory for students aiming for a medical degree until 1833, but nevertheless it remained a well-attended course throughout Young's tenure. In 1780 he resigned his post as professor and proposed his re-election alongside Alexander Hamilton (1739-1802). He was soon re-elected with Hamilton and the two shared teaching responsibilities with one beginning a course as the other finished.
Young is known to have written an essay on puerperal fever that was read before the Philosophical Society of Edinburgh but which was never published. His interest and concern over puerperal fever was also noted by Charles White (1728-1813) in his Treatise on the Management of Pregnant and Lying-in Women. Originally published in 1772, a letter from Young in the postscript states that he had had no problems with fever on his ward and there had been very few deaths in recent months following delivery. This contrasts greatly with the letter published in the 1785 version of White's Treatise in which Young instead describes the numerous fatalities that occurred as a result of an outbreak of puerperal fever on his ward in 1773 and the lengths he went to to rid the place of the disease.
In March 1754 Young married Barbara Gibson, who outlived him by a number of years, but with whom he had no children. Young died quite suddenly in January 1783 from a sudden fit of apoplexy at the age of 57. A contemporary notice of his death notes that he left behind an ample fortune and that after providing for his wife it was divided up between family members, making particular provision for those who needed his assistance most.