SAO PAULO, May 12 (Reuters) - Brazil's stock exchange operator B3 SA Brasil Bolsa Balcao on Thursday reported a 12.3% drop in first-quarter net profit from a year earlier as trading volumes fell amid higher interest rates.

B3's net income was 1.1 billion reais ($214.25 million), roughly in line with an expected 1.27 billion-real profit from analysts polled by Refinitiv. ($1 = 5.1342 reais) (Reporting by Gabriel Araujo Editing by Chris Reese)