(CBS SF) — In an interview about her upcoming memoir, “Becoming,” Michelle Obama opened up about a struggle many American women know all too well, but often feel they can’t discuss publicly: infertility and miscarriage.

Obama divulged that she and former President Barack Obama lost their first baby to a miscarriage, and conceived their two daughters through in vitro fertililzation.

“It turns out that even two committed go-getters with a deep love and robust work ethic can’t will themselves into being pregnant,” she writes in the candid new book.

The former first lady also slammed President Donald Trump for perpetuating the “birther” campaign questioning her husband’s citizenship, calling it bigoted and dangerous, “deliberately meant to stir up the wingnuts and kooks.”