New York, Oct 27 (IANS): Women who were underweight as teenagers or in their mid-30s are at greater risk of facing an early menopause compared to lean or normal weight women, researchers have warned.

Early menopause, defined as naturally occurring menopause before age 45, is associated with a higher risk of cardiovascular disease, and other health conditions such as cognitive decline, osteoporosis and premature death.

The results showed that women who were underweight at any age (BMI of less than 18.5 kg/m2) had a significant, 30 per cent increased risk of early menopause compared with lean or normal weight women (BMI between 18.5-22.4 kg/m2).

Overweight women with BMIs between 25-29.9 kg/m2 had a 21-30 per cent lower risk of early menopause compared to normal weight women.

Further, women who were underweight at age 18 with a BMI of less than 17.5 kg/m2 had a 50 per cent higher risk of early menopause compared to lean or normal weight women.

Women who had a BMI of less than 18.5 kg/m2 at the age of 35 had a 59 per cent increased risk.

Underweight women who reported "severe weight cycling," losing 20 pounds or more three times or more between the ages of 18 and 30, had a 2.4-fold increased risk of early menopause, the authors report.

"Our findings suggest that women who are underweight in early or mid-adulthood may be at increased risk for early menopause," said lead author Kathleen Szegda, a faculty member of the University of Massachusetts Medical School.

"Our findings suggest that being underweight may have an impact on the timing of menopause -- experienced by up to 10 per cent of women," Szegda noted.

For the study, appearing in the journal Human Reproduction, the team evaluated nearly 80,000 women, between ages 25-42.