Brooke Shields says postpartum depression is more prevalent than anyone wants to admit, and that it's time for US lawmakers to pass legislation to help new mothers.

"There is an entire population of women suffering," the actress told George Stephanopoulos in an interview broadcast today on ABC's This Week.

"And it's time, I believe, for Congress to step in and prevent that, and actually save lives and save potential tragedy," she said.

Shields made headlines last year when she acknowledged taking antidepressants after her first child was born - and Tom Cruise publicly criticised her for using the drugs.

She told Stephanopoulos that she experienced acute postpartum depression after the birth of her first daughter, and it was devastating to her family.

"I had gone through numerous attempts to have a baby, and then I finally did have this perfect, beautiful, healthy baby, and it all but destroyed me," she said.

She said a bill being considered by Congress would be "an easy gift to give to women everywhere."

AP