Michelle Obama is opening up about her difficult journey to motherhood in an exclusive interview with ABC News anchor Robin Roberts airing this weekend that's pegged to her upcoming memoir.

In a clip from the special shared on "Good Morning America" Friday, the former first lady revealed that she suffered a miscarriage, which left her feeling “lost and alone.” She writes about her fertility issues in her book.

“I felt like I failed, because I didn't know how common miscarriages were because we don't talk about them,” Obama, 54, told Roberts of the incident that happened about two decades ago. “We sit in our own pain, thinking that somehow we’re broken. So, that's one of the reasons why I think it's important to talk to young mothers about the fact that miscarriages happen, and the biological clock is real.”

The "Becoming" author and former President Barack Obama were able to welcome daughters, Malia, 20, and Sasha, 17, through IVF.

"I realized that as I was 34 and 35," she said in the interview. "We had to do IVF."

Obama explained it's her desire to help other women motivates her openness.

“I think it's the worst thing that we do to each other as women, not share the truth about our bodies and how they work, and how they don't work," she said.

In her memoir, out Nov. 13, Obama also details the early days of her relationship with her husband, including their first kiss.

“As soon as I allowed myself to feel anything for Barack,” Obama writes in her book, “the feelings came rushing -- a toppling blast of lust, gratitude, fulfillment, wonder.”

The former occupants of the White House who have been married since 1992 have a union that has benefited from therapy.

“Marriage counseling for us was one of those ways where we learned how to talk out our differences,” Obama informed Roberts. “I know too many young couples who struggle and think that somehow there's something wrong with them. And I want them to know that Michelle and Barack Obama, who have a phenomenal marriage and who love each other, we work on our marriage. And we get help with our marriage when we need it.”

The pages of "Becoming" also include heavy criticism for President Trump. Obama specifically rips him for his behavior toward women. She denounces him over the infamous 2005 "Access Hollywood" tape, which was released weeks before the 2016 election, in which he bragged about sexually assaulting women. She also criticizes him for his debate behavior toward 2016 presidential candidate Hillary Clinton.

Contributing: Bill Keveney, The Associated Press