UPDATE 1-Delivery Hero ups revenue guidance on rising orders, ad revenue

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April 25 (Reuters) - German online takeaway food company Delivery Hero on Thursday raised its revenue guidance for the year, after reporting better-than-expected growth in the first quarter, on rising orders and advertising revenue.

It now expects revenue to rise in a range of 18%-21%, up from previously expected 15%-17%.

The outlook may reassure investors who have worried that food delivery companies have struggled to retain customers in an overcrowded market after the boom during the pandemic when people treated themselves during lockdowns.

Quarterly total segment revenue increased 21% to 3.02 billion euros ($3.23 billion) in constant currency and excluding hyperinflationary accounting. In reported currency, it grew 17% to 2.95 billion.

The results compare to the 2.81 billion estimated by analysts in a company-provided poll. ($1 = 0.9337 euros) (Reporting by Linda Pasquini; Editing by Josephine Mason)