Serena Williams asked for pregnancy advice on Twitter.

The 35-year-old professional tennis player is currently expecting her first child with fiancÈ Alexis Ohanian, and on Wednesday, she took to Twitter and admitted to tell 8.81 million followers that she is struggling to turn over due to her bump and wanted to know if anyone had any tips.

She wrote: "Any tips on how to turn over at night? I'm having trouble going from my left ... To my right ... to my left side. (sic)"

On the whole, Serena has had a pretty easy pregnancy although she has been "disappointed" to not get any weird cravings.

She previously said: "I have been really fortunate and I have had a really good pregnancy, and everything has just been really good.

"Sometimes I am walking in my house, and I'm like, 'I really like being pregnant.' I never thought I would say that. I am definitely [the type] that enjoys it. I don't have the cravings. So I am a little disappointed with that."

In the absence of any cravings, Serena - whose sister Venus is also a top tennis player - has continued to maintain a healthy diet and stay fit as she "normally" would by eating as much fish and as many vegetables as possible.

She explained: "I have just been trying to eat healthy and stay fit and definitely eating healthier than I normally do. It's pretty backwards ... lots of greens, lots of vegetables ... either fish or different types of nuts and seeds."