Michelle Obama's highly anticipated memoir, Becoming, is finally here, bringing her accompanying press tour along with it. The latter may have just started, but Obama has already jumped right into it: Even just a clip of her primetime ABC News special, which airs in full on Sunday, is making waves, thanks to an excerpt of her candidly discussing the miscarriage she went through two decades ago.

At the time, Obama told Good Morning America anchor Robin Roberts, she and Barack Obama had their minds on her so-called "biological clock" and were aiming to start a family. Around five years after they married, the pair discovered that that wouldn't be as easy as they'd thought. After her miscarriage, Obama, who was unaware of any other women going through the same experience, felt herself fill with shame. "I felt lost and alone, and I felt like I failed," she told Roberts. "I didn’t know how common miscarriages were because we don’t talk about them—we sit in our own pain, thinking that somehow we're broken."

Sasha, Barack, Michelle, and Malia Obama in August, 2016.

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"I think it’s the worst thing 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 continued. (To be fair, that's certainly easier for a former first lady to say than a woman without as much experience or resources.)

The Obamas, of course, eventually welcomed their daughters Sasha and Malia, now 17 and 20, into their family—a result, Obama told Roberts, of IVF, or in vitro fertilization. "I realized that as I was 34 and 35, and we had to do IVF," she said. "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 because egg production is limited."

Obama also gave a preview of how she goes into more detail about her relationship with Barack, from their first kiss to their experience with marriage counseling, in the book. "I know too many young couples who struggle and think that somehow there’s something wrong with them," she told Roberts. "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."

Michelle Obama Finally Opens Up About That Awkward Inauguration Gift Exchange with Melania Trump
Donald Trump, Michelle Obama, Melania Trump, and Barack Obama at Donald Trump’s inauguration, January 2017.

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Family turns out to also be the reason why, as she puts it in Becoming, she'll "never forgive" Donald Trump, whom, now that she's out of the White House, she's clearly comfortable with directly criticizing. That's especially true when it comes to Trump's "crazy and mean-spirited" birther conspiracy, which she described as more than just thinly veiled xenophobia and bigotry.

"It was also dangerous, deliberately meant to stir up the wingnuts and kooks," she writes in the book, continuing on to a resounding conclusion: "What if someone with an unstable mind loaded a gun and drove to Washington? What if that person went looking for our girls? Donald Trump, with his loud and reckless innuendos, was putting my family’s safety at risk. And for this I’d never forgive him."

Related: Michelle Obama Thought Melania Trump's Inauguration Gift Was Awkward, Too