When news got out that Serena Williams' record-breaking win at the Australian Open in January happened while she was almost two months pregnant, the internet lost its cool. Performing like the champ she is was impressive enough—doing so while pregnant has people praising her otherworldly athleticism. We asked an M.D. to give us the dish on how the early days of pregnancy really affect performance for crazy-fit athletes like Serena—and mere mortals prepping for their own athletic feats like a 10-K or Crossfit competition.
"The symptoms of early pregnancy don't discriminate based on athletic prowess," says Leah Millheiser, ob-gyn, assistant clinical professor at Stanford University Medical Center. "In terms of performance, the most common effects around three to four weeks—like fatigue and breast tenderness—could be significant or they could be absolutely zero. It varies from woman to woman," she says.
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In other words, Grand Slam Serena might have been pushing through nasty fatigue and killer breast pain with every serve, or she might have been just fine when she earned her 23rd Grand Slam singles title.
While the kind of shape Serena was in physically wasn't a factor in how her early pregnancy affected her win, her mental shape might have been, says Millheiser. "The reason Serena Williams is who she is is not just because she's a great tennis player—there's a mental side to being a great athlete. Even if she was having mild symptoms in those first few weeks of being pregnant, she might have been able to push through that more than other people because that's what she's been trained to do."
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When it comes to your own performance in the early days of pregnancy, Millheiser says rule number one is to check in with your OB. "Every woman has to talk to her doctor about the kind of activities they want to do and make sure it's okay with their particular pregnancy, since every case is different." (Dance your way fit with Women's Health's High-Intensity Dance Cardio DVD!)
If you're having a normal, healthy first trimester and are given the all clear to run that half you've been training so hard for, Millheiser suggests mitigating any nausea and breast tenderness with a little stomach soothing ginger and one hell of a supportive sports bra.