Even having a family history of breast cancer in a first degree relative carries about a twofold increase in risk.

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Another study published this week suggests that the more a woman earns relative to her partner, the greater the risk of a family breaking up, whereas higher male earnings increase the chances of its survival.

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But having a family history of breast or ovarian cancer can significantly increase the risk of developing breast cancer and at a younger age, although most women with a relative with breast cancer are not at a substantially increased risk themselves.

BBC: Health