Women with diabetes have around a 40% increased risk of suffering a heart attack compared with diabetic men, two studies have suggested.
Those aged 45 to 84 have a significantly higher chance of heart attack, one study found, with the risk largest between the ages of 45 and 54.
Separate research found that women with diabetes of any age were at higher risk of heart attack and angina.
The studies were presented at the European Association for the Study of Diabetes conference in Stockholm.
In one study in Tuscany, Italy, experts analysed differences between diabetic men and women for heart attack, stroke and congestive heart failure.
Dr Giuseppe Seghieri, from the regional health agency in Florence, led the research on more than three million people and found an increased risk for women of all three conditions, but particularly heart attack.
The authors concluded: "With respect to (heart attack), diabetic women are more disadvantaged, compared to diabetic men, with a gender driven 'risk window' for women which mostly opens around menopausal age (45 years onwards).
"Regarding (stroke and congestive heart failure), it opens later, in the postmenopausal age (55 years and over), and to a lesser extent."
Separate research pooling information from 19 studies found that women with diabetes were around 40% more likely to suffer heart attack or angina than diabetic men.
The research included data from almost 11 million patients across the world.
Dr Xue Dong, from the Zhongda Hospital of Southeast University, Nanjing, China, led the study.
He and his colleagues concluded: "Women with diabetes have a roughly 40% greater excess risk of acute coronary syndrome (heart attack and angina), compared with men with diabetes."