Katharine McPhee Says Body Image Issues 'Played with My Mind a Little Bit' amid Pregnancy

Katharine McPhee is speaking candidly about the body image struggles she faced during her pregnancy.

The singer and actress, 37, appeared on Katherine Schwarzenegger Pratt's Instagram Live series Before, During and After (BDA) on Thursday, where she opened up about how being pregnant with her son Rennie, now 11 months, affected how she looked at her body.

"Even though you know your body is going to change, and you expect that, if you're someone who has control issues with your body … psychologically, it just does something different," McPhee explained.

"It played with my mind a little bit," added the star, who shares her only child with husband David Foster.

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McPhee, who has shared in years past that she struggled with eating disorders, noted that she was scared to gain extra weight during her first trimester when she was more hungry than normal.

"I was losing control and I was going back to this old disordered version of myself, which was upsetting because I just wanted to enjoy my baby," McPhee said. "I actually called my old psychiatrist, from when I was in a program in my early 20s, and he came and sat with me, and said, 'What's going on?'"

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Explaining that her psychiatrist told her that the feelings she was experiencing were normal and to be expected, McPhee also noted that she was seeing a food specialist at the time as well, but she decided to attend fewer appointments with them and let her body figure out her eating situation on its own.

"The way I was able to overcome disordered behavior, in terms of food, was not obsessing and letting my body tell me what was needed," she said. "Not being like, 'It has to be oatmeal in the morning, four ounces of protein,' because that makes me crazy."

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During the candid conversation with Schwarzenegger Pratt, 32 — who is currently expecting her second child with husband Chris Pratt — McPhee also shared advice about self-love that she has learned over the years.

Noting that "it's a big responsibility to answer a question like that," McPhee said, "I don't know that there's like a secret recipe for it, right?"

"For me, I had to take the steps, walk through it, to kind of find self-love. I think it's reasonable to say that you don't always have moments of self-love," she continued. "I really struggled during that first trimester. It was difficult for me to find that self-love, self-appreciation."

Added McPhee: "But then I found it later, [and] I think how I found it ... is something that I'll now carry with me. ... I really feel like having conversations with yourself are important, because I'll often find myself talking through a situation, like you'd have with a girlfriend, but to yourself."