I don't know if the rules have changed (I finished residency last year), but the spring after I started residency I applied for economic hardship deferment using my income tax form from the previous year - since you presumably only worked half the year for the first year. Deferment is better than income-based repayment because your subsidized loans won't accrue interest for the year. After the year of deferment, it might be worth then going into forbearance (I assume they let you still do that for being in residency?) because your interest doesn't capitalize until the end of the period of forbearance and it gives you more flexibility about how much/when you pay rather than being required to pay a monthly amount unless you think that just means you won't pay anything (at least get enough for your student loan interest deduction!).
While in residency, I agree with staying frugal in general. Does your program offer a 401K match? That's the first place I would put any extra money up to getting the full match. Then I would fully fund the Roth IRAs since you probably won't be able to do that in the future. After that, unless you're sure that you want to work with populations/in areas that would provide loan forgiveness (and even then, would those programs cover all your loans anyway? I'm guessing there's a limit below your total loans), I would repay the debt aggressively as much as you can. Every dollar you pay towards that debt now is a guaranteed 6.8% return. While it's likely that once your salaries increase, the debt becomes easier to repay, the more you pay off now, the more interest you save, and the more choices you have later - you can make career choices without feeling as burdened by your debt, you can think about buying a house earlier (since you currently essentially have a mortgage), etc. And what if you end up hating medicine or one of you decides to be a stay-at-home parent or develops a health problem or whatever? You just never know exactly what the future holds - that future salary is not guaranteed and it's best to keep your options open by having as little debt as possible. Student loans will stay with you even through bankruptcy.
The other thing I would say is that your salaries now probably seem low in terms of your actual hourly wage and in comparison to future earnings. But the key is to realize that you two actually have a pretty nice income even now (take a look at median household income in the U.S.). I ended up saving more than half my income in residency even while traveling often, but most of my fellow residents ate out frequently, went shopping often, etc. and I can totally understand because we work long hours, we need to de-stress, and we will likely make plenty of money in the future. But if you can get into more of a MMM mindset (
http://www.mrmoneymustache.com/2012/04/18/news-flash-your-debt-is-an-emergency/), you'll realize that your huge debt is a chain that can weigh you down enough to not go for that fellowship you're interested in, or not to move to that city you've always loved, or whatever. And if you're interested in early retirement/financial independence, the sooner you'll attain that by paying off your debts. I know plenty of older physicians in good-paying jobs who are still paying off student loans decades later because they don't know how to save money.
Oh, and I know I've already written a novel, but this just caught my eye:
My husband thinks that the loans are not really worth worrying about during residency because our debt is so big that anything that we could manage to do would have very little impact on the total.
That just doesn't make any sense. Think of it this way: let's take just $1000 of that debt so it's easier to think about. If you pay it off now, it's gone. If you don't pay any of it, it will accrue $403.60 extra in interest by the end of 5 years of residency (assuming capitalization in interest every month). Even if you go into forbearance and the interest capitalizes at the end, that's still $340 of interest. Every $1000 extra you can throw at your debt right now will save you over $400 by the end of your residency! The more you can throw at your debt, the better off you are. It's hard to get that kind of guaranteed return in the stock market. The fact that your debt is so big should make you *more* motivated to pay it off, not *less*! If you paid nothing towards your debt during 5 years of residency, your debt would go from $233,000 to $327,000 at the end of 5 years (nope, not a typo).
Oh, and even if you disagree with me about all of the above, it's at least worth looking into possibly making some student loan payments by the end of this year to get at least a student loan interest deduction on your taxes for this year, depending on your tax situation (your income may be low enough for this year that it may not matter though).