Antidepressant use is common in women. However, characteristics associated with duration of use remain unclear. We conducted a descriptive study using data from the 1973-1978 and 1946-1951 birth cohorts of the Australian Longitudinal Study on Women's Health linked to antidepressant dispensing records from the Pharmaceutical Benefits Scheme, July 2012 to December 2019 to examine use patterns and their associated characteristics. Early discontinuation and prolonged antidepressant use were common, a significant deviation from current guideline recommendations. There were 5553 episodes of antidepressant use in 4416 women, with a mean estimated duration of first-time use of 664 days. One in four women had only one prescription filled, while 32% continued treatment beyond two years, with 14% continuing use at five years. Age and previous antidepressant use impacted duration of use, with a shorter average duration of use and a higher proportion of discontinuation for each subsequent episode after the first prescription.