Article about the topic prior to the birth of the twins:
If Roger Federer thinks becoming a father will have little impact on his goal of equalling and then breaking Pete Sampras's record of 14 grand slam titles he might be in for a rude awakening.
Federer excitedly announced his news last month, declaring: "It's not going to really disturb my mindset on tennis a whole lot", but any parent who has had to deal with sleepless nights may think the Swiss is deluding himself.
While Federer and his girlfriend Mirka Vavrinec eagerly await the arrival of their first child, his fellow professional Ivan Ljubicic had a word of warning.
"I'm sure it's going to be a shock for him. There's no question about that," said the Croatian, who is still trying to come to grips with the demands of his five-month-old son.
"It's just that your life changes completely. Priorities are different. You're not the one in the family who's the most important. You kind of lose your wife for a while."
In case Federer thinks grand slam champions like him can easily buck the trend, he would do well to flick through the record books.
The last time a mother won a singles grand slam crown was in 1980 when Australian Evonne Goolagong triumphed at Wimbledon. Since then, only eight men have captured a major after embracing the joys of fatherhood.
While four - Pat Cash, Andres Gomez, Petr Korda and Albert Costa - were one-slam wonders, multiple champions Boris Becker, Yevgeny Kafelnikov and Andre Agassi managed to add just one further slam to their haul after becoming parents.
Jimmy Connors was the only singles player to successfully combine family life with playing on the tour in that time, winning three of his eight majors after the birth of his son Brett in August 1979.
For the likes of John McEnroe, Ivan Lendl and Stefan Edberg, the titles dried up as soon as they gingerly cradled the new additions to their families.
Tennis fathers have won only 10 of the last 115 grand slam titles.
"(Fatherhood) changes (your) life dramatically," explained Becker, who won the 1996 Australian Open after the birth of his first son Noah.
"It would be more difficult to focus on one thing alone because your main focus is for your child and your wife, and tennis becomes secondary. That's a fact."
If the tennis annals are to be believed, the arrival of Federer junior could end the world number two's chances of adding to his collection of 13 grand slam titles.
The Swiss has remained cagey about exactly when his baby is due, with his only comment being: "The baby is due in summer. I'm not going to say any more."
His reluctance to be more specific has sparked theories that the arrival of baby Federer could coincide with any of the three remaining majors - the French Open in May, Wimbledon in June or the US Open, where he is the defending champion, in August.
While Federer is ready to embrace the next stage of his life, it is hard to imagine the 27-year-old swapping his racket for regular nappy-changing duties.
"I always had the dream that once I became number one in the world that if I have a child I hope I have it early enough so he can see me playing," said Federer. "So this is very exciting."
Apart from the Sampras record, Federer still yearns to get his hands on an elusive title at the French Open, where his great rival Rafael Nadal has ruled since 2005.
Already struggling to find a way to beat players such as world number one Nadal and Andy Murray - against whom he has 6-13 and 2-6 losing records respectively - the prospect of turning up bleary eyed for a major final could cost him dearly.
With his record of achievement and his strong mental outlook, Federer could perhaps succeed where many of his predecessors failed.
"Roger always handles the pressure and I'm sure he's going to do the same with this," said Ljubicic.
"He enjoys this sport so much that he doesn't really need to be focused 24 hours a day to play well."
Federer, who has already committed himself to play on until at least the 2012 London Olympics, added: "If it does something to me, I think it's going to motivate me to play for a long time."