From Longman Dictionary of Contemporary Englishin the clubin the clubBABY/HAVE A BABY British English old-fashioned if a woman is in the club, she is going to have a baby – used humorously SYN pregnant → club
Examples from the Corpus
in the club• Prosecutors allege Combs was illegally carrying a gun in the club.• The strain of having him in the club practically all the time had been hard enough.• Now Alice had asked her to ride Jack Rabbit, her pony, in the club horse show!• The weather was wet and chilly and this run underlines the standard that White is setting in the club this year.• Millionaire computer tycoon Alan Sugar, a lifelong Spurs fan, bought a 48 percent stake in the club earlier this year.• The other intelligence services also proliferated, and there were dark tales in the clubs and messes of rivalry and hatred.• And they huddled together in the club for warmth, and safety, and the strength that came with family feeling.• It happens a few times where I have to pummel one of these guys who causes trouble in the club. 