A lawyer opened a sex discrimination trial Thursday by accusing the U.S. arm of Swiss drug company Novartis of discriminating against 5,600 female sales representatives, saying they are denied promotions and equal pay and sometimes face a hostile workplace.

Attorney Katherine Kimpel acknowledged to the jury in federal court in Manhattan that the company has extensive written materials warning against discrimination but accused it of "saying one thing on paper but another thing in real life."

She said women hired since 2002 entered a company that disrespects and undermines its female workers, resulting in lower pay, fewer promotions and sometimes a hostile workplace dominated by an "old boys network."

She said the discrimination was especially severe for women who became pregnant. Sometimes, she said, they faced managers who fished through their work looking for ways to spoil their careers or pressured them to take shorter leaves or to work while they were on leave.

Novartis attorney Richard Schnadig said the company does not discriminate against women and there was no glass ceiling.

"This is a fair, decent, responsive company that has been sensitive to women's' needs," he said. "We don't discriminate. ... the company makes no claims that we're perfect."

Schnadig said 70 percent of its sales managers are men because the demographics of the workplace have not yet recovered from the days when fewer women entered the work force. He said the company has 14,000 U.S. employees with significant numbers of senior positions held by women, some of whom will testify at the trial.