The Year 2008 itself saw alarmingly high suicide cases in US army more due to the stress in the Iraq and Afghanistan operations. A latest report by the US army is said to be indicating a far higher number of suicide cases in 2009, which can in turn put pressure on Obama to reconsider sending additional troops to Afghanistan.
If he does not send additional troops, then he is risking the lives of the troops stationed in Iraq and Afghanistan. So either way it looks to be a losing game for Obama.