Hormone replacement therapy (HRT) cuts the chance of a woman needing repeat knee or hip replacement surgery by around 40%, research suggests.
Taking the treatment - used to combat symptoms of the menopause - for at least six months after a joint replacement cuts the risk of revision surgery by around 40% while taking it for at least a year could reduce the risk by 50%.
But taking HRT before the surgery had no effect, the study found.
A fall in oestrogen levels causes the majority of menopausal symptoms such as hot flushes, night sweats and thinning of the bones.
HRT, which can be taken as a cream or gel, tablet, patch or implant, helps combat this fall.
Writing in the journal Annals of the Rheumatic Diseases, experts said research has shown that oestrogen deficiency has a negative impact on bone tissue around joint implants.
Meanwhile, HRT is thought to minimise bone loss and improves the growth of bone around the implant.
More than 2% of implants usually require further surgery within three years, mostly because of a condition called osteolysis.
This occurs when particles from the implant seep into surrounding tissue, which causes inflammation which then destroys the bone around the implant.
Today's research looked at women having a first knee or hip replacement between 1986 and 2006.
Overall, 8,100 women who had not used HRT were compared with 2,700 who had taken it for at least six months.
The risk of repeat surgery was tracked in both sets of women for a minimum of three years, with those taking HRT for six or 12 months after surgery found to have a lower rate of revision compared with non-users.
The findings held true even after taking account other factors, including the use of other drugs that can affect bones.
Last June, the British Menopause Society sought to reassure patients over the risks of HRT, saying the benefits outweighed any potential harm for women in their 50s.
Some studies have linked HRT to an increased risk of heart disease and breast cancer.Suggest a correction