Perimenopause -- the transitional phase before menopause -- may raise the risk of depression among women by 40 per cent, according to a study on 1 May.

The study by researchers from the University College London (UCL) is based on a meta-analysis of seven studies involving 9,141 women from across the world, including Australia, the US, China, the Netherlands, and Switzerland.

Compared to premenopausal women, the results published in the Journal of Affective Disorders found that perimenopausal women had a significantly higher risk (around 40 per cent) of experiencing depressive symptoms and being diagnosed with depression.

The finding highlights the "clinical need for screening and support in this potentially vulnerable group".

No significant increase in depression risk was found for postmenopausal women compared to those who were premenopausal.

"This study shows that women in the perimenopausal stage are significantly more likely to experience depression than either before or after this stage," said senior author Roopal Desai, from UCL's Psychology & Language Sciences.

"Our findings emphasise the importance of acknowledging that women in this life stage are more vulnerable to experiencing depression. It also underlines the need to provide support and screening for women to help address their mental health needs effectively," she added.

Mindfulness and cognitive behavioural therapy can be helpful, according to a previous study by the same researchers.

Perimenopause, which occurs three to five years before the onset of menopause, causes fluctuation in oestrogen and progesterone levels. This leads to mood changes, irregular menstrual cycles, and other menopausal symptoms, including increased feelings of depression.

This stage of menopause continues until one year after a woman’s last period and can often last for between four and eight years in total.