It’s not every day that a woman competes and wins in the U.S. open at 8 weeks pregnant. Then again, not every woman is Serena Williams. However, in the days and weeks after Williams gave birth to her daughter, Alexis Olympia, in September, things weren’t as peachy.

According to a recent interview with Vogue, Williams explains that her baby’s heart rate dropped when she started having contractions, prompting and emergency cesarean section that was performed without issue. "And then everything went bad," the 36-year-old told the magazine. But it wasn’t the baby who was at risk this time, it was Serena herself.

Despite being a world-class athlete, the tennis star has a history of blood clots, for which she takes blood thinners. However, after her C-section, Williams went off her medication to heal from the surgery. A couple days later, the tennis champ found herself struggling to breathe while recovering in the hospital. Not wanting to panic her visiting mother, Williams ventured into the hallway and found a nurse, whom she asked for a herapin (a blood thinner) IV and a CT scan. Kind of a boss move for a person that just made another person. The attending doctor ignored Serena's requests (for shame!) and gave her an ultrasound that came back clear. Williams insisted however, and thank god for that, because the CT scan revealed several small blood clots in her lungs.

Unfortunately, it wasn’t as simple as hopping back on her medication. Serena had to go into surgery to correct the pulmonary embolism (that’s a lung clot for all you lay folk), and that’s when doctors found a large hematoma (clotted blood in the tissue) in her abdomen that had been caused by the very blood thinners she had resumed. Finally, after a week, Williams was able to return home.

Understandably, she wasn’t able to enjoy her newfound motherhood right away and spent six weeks in bed. Williams admitted that she felt depressed at times. "No one talks about the low moments. The incredible letdown every time you hear the baby cry. Or I'll get angry about the crying, then sad about being angry, and then guilty, like, 'Why do I feel so sad when I have a beautiful baby?' The emotions are insane," she said. She'll be dominating both motherhood and the courts soon enough, and we won't be surprised.