MEXICO CITY, Feb 13 (Reuters) - Mexican cement producer Cemex posted an unexpected fourth-quarter loss, logging hefty one-off charges for impairment of goodwill and fixed assets.

It swung to a net loss of $99.1 million from a profit of $194.8 million in the same period a year earlier. Analysts had expected profit to climb after the company hiked product prices by double-digit percentage figures.

Revenue did increase, surging 8% to $3.87 billion with robust sales growth seen in Mexico and the United States, although overall volumes dipped.

Blaming the global high inflationary environment and increasing interest rates, it recognised a goodwill impairment charge of $365 million. Impairment losses for property, machinery and equipment came to $77 million.

Operating EBITDA (earnings before interest, tax, depreciation and amortization) for the quarter dropped 2% to $630.46 million.

Cemex's operating EBITDA margin was 16.3%, down from 18% in the year-earlier quarter.

"The contraction was the lowest of the year," Chief Executive Fernando Gonzalez said in a statement. "I am seeing growing evidence that actual margin recovery is underway." (Reporting by Kylie Madry and Noe Torres; Editing by Edwina Gibbs)