Serena Williams revealed she suffered major health complications in the days after she gave birth to her daughter, Alexis Olympia, that left her bedridden for her first six weeks of motherhood.

Williams, 36, opened up to Vogue for the magazine’s February issue — sharing the cover with her baby — and talked about her “greatest medical ordeal” that began with the emergency C-section. The tennis star said she had an “enviably easy pregnancy,” but was rushed into surgery when the infant’s heart rate dropped dangerously low during labor.

“That was an amazing feeling,” Williams said when she heard Alexis’ first cry. “And then everything went bad.”

Williams said she felt short of breath the next day and suspected she was having a pulmonary embolism, when blood clots block one or more arteries in the lungs. She had stopped taking her daily anticoagulant regime because of her recent procedure. Williams insisted she get a CT scan and blood thinners despite the nurse’s skepticism.

“I was like, a Doppler? I told you, I need a CT scan and a heparin drip,” Williams recalled.

After the ultrasound turned up empty, doctor discovered several small blood clots in her lungs.

“I was like, listen to Dr. Williams!” the tennis star said.

The ordeal continued for another six days. She went back into surgery after her C-section wound burst open from intense coughing fits. Doctors then found a hematoma flooding her abdomen — caused by a chain reaction from her blood thinners that led to hemorrhaging at her C-section wound.

She went back to the operating room so doctors could place a filter in a vein to prevent more blood clots.

Williams went home a week later, but was unable to leave her bed for six weeks. She also didn’t have a night nurse to take care of her daughter. Reddit co-founder Alexis Ohanian, who Williams married in November, told Vogue he was happy to step in and take care of baby duties while Williams rested.

“I was happy to change diapers,” Ohanian said. “But on top of everything she was going through, the feeling of not being able to help made it even harder. Consider for a moment that your body is one of the greatest things on this planet, and you’re trapped in it.”

Williams said the first few months of being a mother has caused her to break down countless times, adding that the “emotions are insane.”

“No one talks about the low moments — the pressure you feel, the incredible letdown every time you hear the baby cry,” Williams said. “I’ve broken down I don’t know how many times. 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.”

Despite the struggle, she said the family is doing well and is even considering having more children, but added she is in “no rush.”

Williams said she is ready to get back on the court and is expected to return in March for the BNP Paribas Open, also known as the Indian Wells Masters.