The navy continues to add more women to ship crews. But in the last few years it has discovered a problem it had not anticipated; women seek medical help ("sick call") six to ten times more often than male sailors. If crews are to eventually be twenty percent women, this will mean medical staff on ship will have to be doubled to handle the workload. Before the latest study was published in a military journal, the official navy line was that female sailors only used sick call sixty percent more than men. Ship's officers are under a lot of pressure to make "mixed crews" work and are encouraged (if they value their promotion prospects) to play down any behavior that would reflect badly on the navy policy.