Is Chrissy Teigen's Second-Baby Theory Legit?

In the week since Chrissy Teigen announced her second pregnancy through an excruciatingly adorable Instagram video, she's been airing her pregnancy questions and musings on Twitter. This weekend, for example, she tweeted: "Can someone just be honest with me and tell me if it's normal to get bigger, faster with [your] second baby? Because I am getting big, fast, and everyone's go-to is 'It's that second baby!' But they're lying. I know it. I can handle the truth, just tell me. It's not normal, is it?" Chrissy, the truth is: It is normal.

For starters, it's not surprising that Teigen is picking up on differences this time around, because no two pregnancies are exactly the same — even ones that take place inside the same body. But there are a few explanations as to why pregnant people who have had a baby before feel like they grow faster and bigger with subsequent kids.

In the replies to Chrissy's tweet, Abby Bales, DPT, a physical therapist who specializes in pelvic and abdominal rehab postpartum, speculated that this could be tied to muscle laxity — and that's legit. During the first trimester of pregnancy, a hormone literally called "relaxin" kicks in and causes joints, ligaments, and muscles loosen, to allow the uterus to grow and make room for the fetus, Bales tells Refinery29.

Then, once that pregnancy has ended, "the uterus retains some extra size, so when the [next] baby is implanted and grows, the uterus is already at a larger size," she says. Plus, during pregnancy, the abdominals can stretch or separate from their ligaments, and they don't always bounce back into place. So, in the first couple of months of a second pregnancy (or third, etc.), the bump appears sooner, she says.

Now, having a stretchier abdominal wall doesn't necessarily mean you're gaining more weight, it just means that you'll show earlier in the pregnancy, explains Lynn L. Simpson, MD, FACOG, professor of women's health in the department of obstetrics and gynecology at Columbia University Medical Center. That said, it is completely normal to gain weight as you age, so many people start their second or subsequent pregnancies a little heavier than they were for their first, Dr. Simpson says. "This extra weight may impact a woman's metabolism, energy level, and amount of activity they engage in — all impacting weight gain in the current pregnancy," she says.

The TL;DR is that it is normal to grow bigger and faster during a second pregnancy, likely due to a combination of changes that occur to a person's body after having a baby. But despite that initial growth spurt, it's not always an indication of how big the belly will get throughout the rest of the pregnancy, Bales says.

So, while it's totally frustrating for Teigen to have to listen to other people parent-splain what's happening to her pregnant body, in this case, they were actually right. And Chrissy, keep tweeting your pregnancy questions, and we'll help you find the truth. As for the mysteries of Animal Crossing, you're on your own.

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