GENEVA, Sept 2: Life expectancy for women at 50 has improved, but the gap between poor and rich countries is growing and could worsen without better detection and treatment of cardiovascular diseas e and cancers, the World Health Organization (WHO) said today. A WHO study, one of the first to analyze the causes of death of older women, found that in wealthier countries deaths from noncommunicable diseases has fallen dramatically in recent decades, especially from cancers of the stomach, colon, breast and cervix. (agencies)