She told the publication that the problems began after Alexis Olympia's heart rate started to drop during her delivery and it was decided that the best option would be to have Serena undergo an emergency c-section.
Doctors ordered an ultrasound but that turned up nothing, she was then sent for a CT scan which revealed blood clots in her lungs.
Having experienced the symptoms before, she assumed she was having a pulmonary embolism and demanded the medical team give her a scan and a blood thinner medication.
'I was like, a Doppler? "I told you, I need a CT scan and a heparin drip", she recalled of the scary time.
"Sometimes I get really down and feel like, man, I can't do this", she said.
Worse still, Williams' C-section wound then broke open due to her intense coughing, US Vogue reports, requiring another surgical procedure, which in turn revealed a hematoma had flooded her abdomen - requiring yet more surgery.
In the end, Williams had to have a filter inserted into a major vein to prevent any possible clots from entering her lungs, and was forced to go on bed rest for the next six weeks.More news: Female BBC News editor speaks out against her employer's 'illegal pay culture'
"It will be cool to see if I get there again, to what I call my spot - where I feel I belong".
"I was happy to change diapers, but on top of everything she was going through, the feeling of not being able to help made it even worse", he said. "(The) incredible letdown every time you hear the baby cry ...
On December 30, she lost an exhibition match against Jelena Ostapenko, the 2017 French Open champion, at the World Tennis Championship in Abu Dhabi.
"Knowing I've got this attractive baby to go home to makes me feel like I don't have to play another match", she explained.
But that's not to be confused with the idea that Serena is anxious about reclaiming her spot as number one when she returns.
We're sure Olympia would have her say in the accompanying feature piece if, you know, she was old enough to talk, but the input from her mum is compelling enough on its own. "All Vogue covers are special but to share this one with my attractive daughter Olympia Ohanian also the youngest Vogue cover star makes it moment I will never forget".
"After competing in Abu Dhabi I realised that although I am super close, I'm not where I personally want to be", she said in a statement on Snapchat.