She was the first woman to be appointed as a divisional surgeon in New South Wales, and a year later was among the first female doctors when she joined the British Expeditionary Forces in Egypt in 1915.

[5] Ardill therefore travelled to Britain, signing up with the British Red Cross who in September 1915 deployed her to serve at the Anglo-Belgian Hospital in Calais.

In mid-1916, Ardill become one of the first women doctors in the British Expeditionary Forces field services, when the army changed their policy to allow the to enlist on a contractual basis.

Serving under the Royal Army Medical Corps, Ardill was deployed to the County Middlesex War Hospital, St. Albans, England.

[7] She then worked at the Anglo-Belgian Base Clearing Military Hospital at Étaples in France,[1] where she was the only Australian woman doctor until 1917,[8] and was later promoted to the rank of captain.