London, Apr 18 (IANS): Being underweight or overweight could significantly increase your risk of experiencing recurrent miscarriages, according to a study.

The study, led by the University of Southampton researchers found that there are higher occurrences of successive miscarriages in mothers who are underweight -- having a Body Mass Index (BMI) score of less than 18.5, overweight (having a BMI between 25 and 30) and obese (having a BMI above 30).

For those with BMI greater than 25 and 30, their risk of suffering a further miscarriage increases by 20 per cent and 70 per cent respectively, the findings published in the journal Scientific Reports revealed.

"Our findings suggest that having an abnormal BMI exacerbates a woman's risk of suffering from repeated miscarriages, and so clinicians really need to focus on helping women manage this risk factor," said Ying Cheong, professor of reproductive medicine at the University of Southampton.

The team conducted systematic review and meta-analysis of 16 studies and assessed the link between women's lifestyle and risk of recurrent pregnancy loss, defined as women having two or more consecutive early miscarriages.

They also set out to assess the impact of factors such as smoking and consumption of alcohol and caffeine. However they were unable to establish conclusively whether these have any impact or not due to inconsistencies of the results from a small number of studies and heterogeneity in women taking part in them.

Whilst recognising that more observational and clinical research is needed to establish the full extent of lifestyle choices, the authors conclude that weight is a risk factor that can be modified to reduce the risk.

Miscarriage is the most common complication of early pregnancy, affecting between 15 per cent and 20 per cent of all pregnancies. Recurrent pregnancy loss is a complex disease and although often attributed to numerous medical factors and lifestyle influences, the cause is deemed "unexplained" in around 50 per cent of cases.