UPDATE 1-Hologic beats estimates as breast health system sales rise

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Feb 3 (Reuters) - Medical device maker Hologic Inc reported a better-than-expected adjusted quarterly profit in part due to higher sales of its 3D digital mammography systems.

Hologic shares rose 4 percent in extended trading.

The company, which settled with activist investor Carl Icahn in December, raised the lower end of its earnings forecast by 2 cents for the year ending September. The company said it now expects adjusted earnings of $1.34 to $1.38 per share.

Hologic posted a net loss of $5.4 million, or 2 cents per share, for the first quarter ended Dec. 28, compared with a net income of $3.1 million, or 1 cent per share, a year earlier.

Excluding items, Hologic earned 34 cents per share, ahead of analysts' average estimate of 31 cents per share, according to Thomson Reuters I/B/E/S.

Revenue fell 3 percent to $612.4 million, but beat analysts' average estimate of $609.7 million.

Sales in its breast health business rose about 3 percent to $226.5 million as the company sold more 3D Dimensions mammography systems.

Hologic has been struggling with lower spending by hospitals, slower growth in the use of its 3D mammography systems due to a lack of reimbursement and falling sales of its cancer detection test. Analysts don't expect these challenges to abate this year.

Icahn disclosed a 12.63 percent stake in Hologic in November. In December, the company appointed two directors backed by Icahn to its board and named former Stryker Corp head Stephen MacMillan as its CEO.

MacMillan replaced Jack Cumming, who was working on a strategic review of Hologic's businesses after taking charge in July.

Hologic maintained its fiscal 2014 revenue forecast of $2.43 billion to $2.48 billion and said it expects a decline in sales of its ThinPrep cancer detection tests, blood screening assays and systems to treat heavy menstrual bleeding.

The company's shares closed down 4 percent at $20.47 on the Nasdaq on Monday.

(Reporting By Vrinda Manocha in Bangalore; Editing by Sriraj Kalluvila)