Howard's panic surrounding the 'Wolobaby' was mainly based around the financial implications of a third mouth to feed, a child to eventually put through college, and every other little expense that a baby can incur, both immediately and down the line. However, Wolowitz could obliterate two birds with one stone if he races to complete a doctorate. That could open the door to a higher-paid job and definitively end all jokes about the rest of the gang being doctors in their fields, unlike Howard.