Katie Couric says Bryant Gumbel gave her a hard time back in the day over maternity ... which Katie thinks spoke to something deeper, even if he was joking.

The famed newswoman stopped by Bill Maher's 'Club Random' podcast Sunday ... in which she detailed the "prickly" relationship she had with Bryant during their tenure on 'Today' together.

Katie hinted she and Bryant were never close, referring to her coworker as a guy's guy -- but still applauded his broadcasting skills.

However, Katie claimed Bryant got a little upset at her for taking a handful of months off to have her first baby at the time. Remember, Katie and her late husband, Jay Monahan, welcomed their first of 2 daughters in 1991 -- not long after she joined 'Today.'

She says ... "He got mad at me because I was doing something on maternity leave. And he was giving me endless s**t for taking like a month or two off. I was having my first baby."

Katie said Bryant then jokingly told her she should drop her baby in a field and return to work. She added ... "It was emblematic of an incredibly sexist attitude."

Katie and Bryant overlapped at 'Today' for 6 years, as BG left the show in 1997 to work for CBS. Katie eventually left the network as well ... famously becoming the first female anchor for "CBS Evening News." We've reached out to Bryant's legal team ... no word back yet.