It would appear that Serena Williams, winner of 23 Grand Slam titles, has it all.

An incredibly successful career in tennis, a loving husband in Reddit co-founder Alexis Ohanian and, of course, the beautiful daughter they share, Alexis Olympia Ohanian Jr.

However, the 40-year-old sports superstar has been vocal about the trauma she experienced in 2017 when she gave birth to the little one, who is now four years old.

In 2018, Williams wrote a first-person piece for CNN, revealing that she had "almost died after giving birth to" her daughter Olympia.

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Now, more than fours years later, the mother of one has written another piece, this time for Elle magazine, in which she goes into detail about how she "saved her own life" during her labor.

Williams explained that she began experiencing a great deal of pain and couldn't stop coughing after giving birth via C-section. However, when she requested that her nurse arrange a CAT scan, it initially fell on deaf ears.

She recalled: "I spoke to the nurse. I told her: 'I need to have a CAT scan of my lungs bilaterally, and then I need to be on my heparin drip.' She said, 'I think all this medicine is making you talk crazy.' I said, 'No, I’m telling you what I need: I need the scan immediately. And I need it to be done with dye.'"

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Williams continued: "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.

"I fought hard, and I ended up getting the CAT scan. 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."

The athlete, who underwent three surgeries after her C-section, says she could have died had she remained silent in spite of her concerns.

"Giving birth to my baby, it turned out, was a test for how loud and how often I would have to call out before I was finally heard," she said.

She then proceeded to highlight the following stat: "In the US, Black women are nearly three times more likely to die during or after childbirth than their white counterparts. Many of these deaths are considered by experts to be preventable."

Featured image credit: Image Press Agency / Alamy

Serena Williams opens up about how she 'almost died' after giving birth to daughter