The tennis star was forced to undergo an emergency caesarean and had surgery for blood clots in her lungs during the birth of Alexis Olympia Ohanian Jr in September last year – her first child with husband Alexis Ohanian, who she married in Rome just 11 weeks later.
Williams told Harper’s Bazaar that although she was now ready to have another child, she had gone through some tough times before returning to the court for the first time at the Fed Cup in North Carolina in February.
“Honestly, sometimes I think I still have to deal with it,” said the 36-year-old, who earlier this year revealed that she “almost died” during the birth.
“I think people have to talk about it more because it’s almost like the fourth trimester, it’s part of the pregnancy.
“I remember one day, I couldn’t find Olympia’s bottle and I got so upset I started crying because I wanted to be perfect for her.”
But things have since taken a positive turn for Williams, who was one of the star guests at the royal wedding of the Duke and Duchess of Sussex.
This week she is making her first Grand Slam appearance in more than a year at the French Open and she could be seeded for Wimbledon in July, despite plummeting down the world rankings during her time off.
Should she win at Roland Garros, it would be her 24th Grand Slam singles title. She is also playing in the women’s doubles with sister Venus.
Despite the already impressive comeback, Williams also told the magazine that she was keen to have another child with her Reddit co-founder husband – and soon.
“If I wasn’t playing tennis, I’d be pregnant right now – sorry, I’m one of those women,” she said.
“I’ve been injured so many times, and played on it, my body is used to adjusting.
“Olympia needs a little sister, and then we can have a boy. I’ve only been around girls my whole life.”
:: What is postnatal depression?
The NHS defines postnatal depression as a common mental health problem affecting parents after having a baby.
While many women feel a bit down, tearful or anxious in the first week after giving birth, symptoms that go on for longer are often a sign of postnatal depression.
It affects more than one in 10 women, but it can often go untraced because the effects – which include a persistent feeling of sadness and struggling to bond with their baby – can come on gradually.
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The NHS advises that you should speak to your GP or health visitor if you think you may be depressed.
Many health visitors are said to have been trained to recognise postnatal depression and have techniques that can help.