"I felt like I was not living up to my potential as a parent, or as an entrepreneur, or as an executive," Trump said. "I had had such easy pregnancies that in some ways the juxtaposition hit me even harder."
When asked why she decided to speak out now, Trump said that she had not been planning to, but believes "it's incredibly important," and added that postpartum depression affects new parents indiscriminately.
"I consider myself a very hard-charging person, I'm ambitious, I'm passionate, I'm driven. But this is something that affects parents all over the country," she said.
Postpartum depression can start anytime after the baby's birth and can last up to a year, according to ABC News senior medical contributor Dr. Jennifer Ashton.
"This can be a life-threatening medical emergency so anti-depression medication is key," Ashton said of postpartum depression on "Good Morning America" earlier this month. "Peer support, psychotherapy and behavioral therapy are all very important."
Dr. Sue Varma, a psychiatrist and clinical assistant professor of psychiatry at the NYU Langone Medical Center, told ABC News earlier this year that women should de-stigmatize postpartum depression and not be afraid to seek treatment.
"Look, you would get help for any other medical problem, right?" Varma said. "And postpartum depression is a medical problem and should be treated like one.
"It's a very common disorder and we really don't give it the proper sort of detection and screening and appreciation that it deserves," Varma added, saying that part of the reason for this may be because people tend to focus all their energy on the new baby, "and women end up neglecting their own needs."
ABC News' Kelly McCarthy contributed to this report