Serena told medical staffers that she needed a CAT scan and a heparin drip. A nurse told her, “I think all this medicine is making you talk crazy.”

In 2017, tennis champ Serena Williams gave birth to her daughter, Olympia, with her husband Alexis Ohanian by her side.

The star has been open about the life-threatening medical complications that she faced after childbirth, which forced her to have four back-to-back surgeries in the space of a week.

Serena suffered several blood clots that could have killed her if she did not receive immediate treatment, but she has now revealed that she had to advocate for herself after medical staffers dismissed her concerns.

In a new essay for Elle, Serena said that she was forced to save her own life as she drew attention to the fact that “Black women are nearly three times more likely to die during or after childbirth than their white counterparts” in the United States.

Instagram: @olympiaohanian

In the United Kingdom, Black women are more than four times as likely to die from pregnancy- or childbirth-related causes than white women.

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In her new piece, Serena said that giving birth ended up being “a test for how loud and how often I would have to call out before I was finally heard” as she shared concerning details from her time in the hospital.

Instagram: @olympiaohanian

She started by explaining that she’d had a “wonderful pregnancy” and that she was induced on Aug. 31, 2017. She even said that she actively enjoyed “the work of labor.”

“I loved feeling my body trying to push the baby out. I wasn’t on an epidural; to get through it, I was using my breath and all the techniques I’d learned from birth training,” she recalled.

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However, when her labor went on into the next day, doctors decided that she should have a C-section as the baby’s heart rate was unstable.

Instagram: @olympiaohanian

“Being an athlete is so often about controlling your body, wielding its power, but it’s also about knowing when to surrender,” Serena wrote. “I was happy and relieved to let go; the energy in the room totally changed. We went from this intense, seemingly endless process to a clear plan for bringing this baby into the world.”

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Olympia arrived safely — but not long after, Serena began to feel unwell. Having suffered a pulmonary embolism back in 2010, she knew that she should be on a heparin drip as she is at high risk for blood clots.

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“So much of what happened after that is still a blur,” Serena explained. “I may have passed out a few times. In my haze, I wondered if I should ask someone about my drip. In 2010, I learned I had blood clots in my lungs — clots that, had they not been caught in time, could have killed me.”

Instagram: @serenawilliams

“Ever since then, I’ve lived in fear of them returning. It wasn’t a one-off; I’m at high risk for blood clots. I asked a nurse, ‘When do I start my heparin drip? Shouldn’t I be on that now?’ The response was, ‘Well, we don’t really know if that’s what you need to be on right now.’ No one was really listening to what I was saying,” she added.

Instagram: @serenawilliams

Serena said that the staff were wary of putting her on blood thinners as it could make her C-section bleed, but she “kept pressing” because she “felt it was important.”

Instagram: @serenawilliams

She was already in “excruciating pain” and unable to move due to the surgery. She then began to cough uncontrollably and struggled to breathe.

“I couldn’t breathe. I was coughing because I just couldn’t get enough air. I grabbed a towel, rolled it up, and put it over my incision. Sure enough, I was hacking so hard that my stitches burst. I went into my first surgery after the C-section to get restitched,” she recalled.

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However, it turned out that Serena was coughing due to a clot in her arteries, with doctors later discovering a hematoma — a collection of blood outside the blood vessels — in her abdomen, followed by “even more clots.”

“I felt like I was dying,” Serena admitted in the piece. “All I could think was, ‘I’m dying, I’m dying. Oh my God.’”

Instagram: @serenawilliams

Despite her panic, Serena said that she approached a nurse and told her that she needed to have a bilateral CAT scan of her lungs and be put on a heparin drip, but the nurse replied: “I think all this medicine is making you talk crazy.”

Instagram: @serenawilliams

“I said, ‘No, I’m telling you what I need: I need the scan immediately. And I need it to be done with dye,’” Serena went on. “I guess I said the name of the dye wrong, and she told me I just needed to rest. But I persisted: ‘I’m telling you, this is what I need.’ Finally, the nurse called my doctor, and she listened to me and insisted we check.”

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“I fought hard, and I ended up getting the CAT scan,” Serena said. “I’m so grateful to her. Lo and behold, I had a blood clot in my lungs, and they needed to insert a filter into my veins to break up the clot before it reached my heart.”

Her experience has understandably shocked many people, and it has also sparked an important conversation about the medical care that Black people receive — with many pointing out that if a wealthy celebrity with access to top hospitals and doctors could be treated this way, there is far less hope for those with fewer resources.

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“Even one as rich, powerful & famous as @serenawilliams cannot escape the bias, pervasiveness & harms of #MedicalGaslighting as long as they are women, Black, or members of other minoritized, marginalized groups,” cardiologist Sharonne Hayes tweeted.

Twitter: @SharonneHayes

Another medical professional wrote: “Don’t be afraid to speak up – Advice from an RN. Serena’s experience makes my blood boil. This is why maternal mortality is so high for Black Women. This is caused by racism. I have always listened to my patients and highly recommend all medical people do too.”

A third person tweeted: “Doctors didn’t even want to listen to Serena Williams, who is likely more in tune with her body than 99.99% of the population. No wonder Black women suffer from maternal mortality at much higher rates.”