"I'm just trying not to overdo it right now," she tells PEOPLE

By Amanda Michelle Steiner and Alicia C. Dennis
Updated April 24, 2015 08:00 AM
Credit: Andrew Southam

As Jessa Seewald awaits the birth of her first child with husband Ben, she’s making it a priority to stay fit and keep healthy.

When she learned that she was expecting – on their first wedding anniversary, no less – Jessa tells PEOPLE that one of the first things on Ben’s mind was, ” ‘What does it mean for your workouts? Let’s adjust them for pregnancy.’ ”

Because they’re both concerned about her potentially straining herself, says Jessa, “I’m just trying not to overdo it right now. I am still working out, but not trying to break any records.”

A particularly health-conscious couple, Ben, 19, was shown putting some of the Duggar clan through their paces on a recent episode of 19 Kids & Counting and Jessa, 23, often posts Instagram photos of her smoothies and other healthy foods.

“I want to gain a little less weight and not stress out about it,” Jessa says. “I do want to make sure that I’m eating healthy. You are eating for two but the other is, like, a speck. I am trying to make healthy choices now that I’m entering my second trimester.”

Fans of TLC’s hit show 19 Kids & Counting – which airs Tuesdays at 9 p.m. ET – can see the birth of Israel David, Jill and Derick Dillard‘s first child, on May 5 in advance of Mother’s Day.

For more on Jessa and Ben Seewald’s pregnancy news, pick up this week’s issue of PEOPLE, on newsstands now

Want more Duggars? Click here to get weekly updates on the stars of TLC’s 19 Kids & Counting in the Duggar Family Newsletter.

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