Katherine Heigl Gets Candid About Her 50-Lb. Weight Gain During Pregnancy

Katherine Heigl has two daughters through adoption, but giving birth to son Joshua Bishop introduced her to the world of pregnancy — and its crazy changes to her body.

The 38-year-old actress shared a blog post about her weight loss journey seven months after welcoming her son with husband Josh Kelley, admitting her 50-lb. weight gain left her with “moments of sheer panic.”

“I had hoped to only gain 25-30 pounds like my mother during her pregnancies but found that just wasn’t possible for me,” she wrote. “Despite starting my gestation out on a pregnancy friendly meal plan and hiking my butt off 5 days a week my weight kept creeping up.”

Heigl continued, “At a certain point, probably around 4 months I gave up the struggle and tried instead to respect my body’s needs and trust my instincts.”

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The Doubt star recalled stepping on the scale about 10 days after the baby’s birth to find that she was “miraculously” down 30 lbs.

The rest of her baby weight has been a bit more stubborn, but Heigl is learning to love her body as is.

“We’ve all heard about the gals who tone up and get right back into their skinny jeans weeks after their babies birth but this was not me, nor was I trying for it to be,” she shared. “I have only lost 10 pounds since that first initial drop but that’s ok because I decided from the start that I was going to lovingly but patiently reclaim my pre baby body, and forgive the glorious imperfections that would forever grace my new post baby body.”

FROM PEN:Katherine Heigl on Pregnancy: ‘My Boobs Got So Ginormous’

Heigl shared some of her tips for getting back to her pre-pregnancy weight, including her favorite smoothie recipes and meal planning websites. However, her best advice had nothing to do with hitting the gym or restricting her diet.

“My best weight loss advice is to start every morning by saying out loud a positive mantra of your choice about your body. Mine is ‘I am easily, with good health, inspiration, grace and gratitude losing weight faster than I can even imagine with harm to none,’ ” she said.

“Then I say my gratefuls. Thanking my body for it’s perfect health, strength, limberness, vibrancy, youthfulness and beauty. Whether I always believe these things about myself and my body or not, I say them. By saying them out loud with love and gratitude I have found that I not only start to believe them, but my body exhibits what I say and believe.”

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Heigl previously opened up to PEOPLE about another physical change due to breastfeeding.

“My boobs just got so ginormous,” she said. “It was horrifying! I’ve always had fairly large breasts, but [I went from a] DD to an I. Did you know that an I even existed in bra sizes? I didn’t. I didn’t know that until I started having to buy bra sizes in an I. That’s D, E, F, G, H, I — that’s horrifying!”

The actress also said that even though she and her family are still adjusting to life with the little guy, she already knows that she’s not done growing her family.

“I’d get pregnant again, and I still am very inspired by adoption. I also have been thinking a lot about fostering. It’s all up in the air,” she said with a smile. “And I’m okay with that!”