She has also opened up about her heartbreaking struggles with infertility.
"I have had eight or nine miscarriages," the 44-year-old star writes in her new book 'We're Going to Need More Wine,' reports People.
"For three years, my body has been a prisoner of trying to get pregnant-I've either been about to go into an IVF cycle, in the middle of an IVF cycle, or coming out of an IVF cycle," she continued.
The actress stated that she never saw children as a part of her future, but after having raised her husband's sons from his previous relationship.
She discovered that having a baby was something she had always wanted.
"I never wanted kids," she told the publication.
"Then I became a stepmom, and there was no place I'd rather be than with them."
Union has been the target of pregnancy rumors like many other celebrities and had constantly been asked whether she wants children in her future and explained that strangers don't understand the 'frustration' or 'harm' continuous questioning can cause to a woman trying to conceive.
"Once a month, I look like I'm in my second trimester because I'm bloated," she says.
"It leads to the questions and it leads to the rumours and anytime I go into a doctor's office I feel like I'm a member of SEAL Team Six undercover because I don't want people to speculate," the 44-year-old actress added.
Union's book, "We're Going to Need More Wine," will be released on October 17. (ANI)