The company, which is listed on the Nasdaq market for hi-tech stocks in the US, said in a statement it had received revised information showing Wipro GE Medical Systems had made bigger losses than reported.
Wipro's 49% share of the incremental loss is 147m rupees (£2m) under US accounting rules and 186m rupees under Indian GAAP results, the company said.
On 19 July, the Bangalore-based company reported a larger than expected net profit of 1.63bn rupees for April-June under Indian accounting rules.
The after-tax profit for the quarter would be cut by the amount lost by the medical unit, Wipro said.
Wipro shares sank nearly 3% after the news on the Bombay Stock Exchange.
The revision comes after the deadline set by the US stock market watchdog, the Securities and Exchange Commission (SEC), for bosses of large US companies to confirm the correctness of their company results.
Market pick-up
Wipro GE Medical Systems, India's largest medical systems sales and service provider in which Wipro holds a 49%, is controlled by GE .
On Wednesday, Wipro's vice-chairman said the industry was recovering from a sharp slowdown.
"The markets are on the mend," Vivek Paul said.
"We are seeing a lot of first-timers. They are now waking up to the fact that technology outsourcing out of India works," he added.
India has become a key outsourcing centre for international companies because of its big pool of low-cost and high-quality engineering graduates.
The past two years have been tough for the company and its rivals because of the global economic slowdown in information technology spending.
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