THURSDAY, Jan. 11, 2018 (HealthDay News) — Though Serena Williams commands the tennis court with ease when she plays, life-threatening complications following the birth of her daughter sidelined her for six weeks.

Williams tells the story of her medical ordeal in the latest issue of Vogue, published Wednesday.

After an easy pregnancy, things turned precarious when she had to have an emergency C-section because the baby’s heart rate was dropping rapidly during contractions. The C-section went off without a hitch and her daughter, Olympia, was born on Sept. 1. But what followed was far from smooth, Williams told the magazine.

The next day, Williams suddenly felt short of breath. Having suffered a pulmonary embolism in 2011 following a fall, Williams knew in her bones what was wrong.

She had a history of blood clots in her lungs and she had been taken off blood thinners before delivery, so she did not waste time telling the nurses and doctors what to do. To make sure her mom wouldn’t worry, Williams said she walked out of her room while gasping for breath and told a nurse that she needed a CT scan and IV heparin (a blood thinner) immediately.

But the medical professionals were not easily convinced. The nurse thought pain medication might be confusing Williams, while a doctor ordered only an ultrasound of her legs. Nothing was found, so they sent her for a CT scan. Williams turned out to be right. There were several small blood clots in her lungs and a heparin drip was started within minutes, she told Vogue.

But the complications did not end there.

After suffering some severe coughing from the clots in her lungs, the sutures on her C-section incision gave way. It turned out that the blood thinner they had put her back on to save her life caused bleeding at the incision site and a large hematoma had filled her abdomen. Yet another surgery was needed, and a filter was inserted into a major vein so that no more clots would find their way to her lungs. Afterwards, she wasn’t able to get out of bed for six weeks, she told Vogue.

Williams is not alone with her post-delivery nightmare.

According to the U.S. Centers for Disease Control and Prevention, one-fifth of the 4 million women who deliver have a serious problem before labor and one-quarter have a serious complication during labor or delivery. And race plays a part in outcomes: the risk of pregnancy-related death is four times higher among black women than it is among white women, the CDC says.

More information

Visit the U.S. Centers for Disease Control and Prevention for more on pregnancy-related complications and deaths.