The dashing wicket-keeper batsman might be granted two to three weeks leave on compassionate grounds to attend the birth of his child.
The news came as further blow with Andrew Symonds already nursing an injury and set to miss the opening matches, besides the team is unsettled by their shock defeat to England in the CB Series finals.
Australia might have to make do without their opening bat at least until their final Group A match against South Africa in St Kitts on March 24, according to a report in the Sydney Morning Herald.
Meanwhile, Brad Haddin has been named in the 15-man World Cup squad as a cover for Gilchrist. However, Haddin will be worth his place in the squad as a specialist batsman, after a prolific domestic season.
''It's such an important tournament that my leaning is to take a second specialist wicketkeeper, but that second specialist wicketkeeper has to offer us more than just wicketkeeping,'' said John Buchanan.
''It has to be able to offer us batting potential and probably top-seven material. That's my personal leaning and I've expressed that to the selectors.'' Gilchrist already had been allowed to be rested from the three-match Chappell-Hadlee series starting this week in New Zealand.
Australia's World Cup pool matches are against Scotland (March 14), The Netherlands (March 18) and South Africa (March 24).