I am in your same situation. I'm 27 (almost 28) and between my husband and I we had over $120K in student loans. We have been working really, really hard to pay them off over the past 5 years and have the amount down to $40K.
What has helped us in the baby decision is making a spreadsheet with all of our expenses and our income. That made us realize that it was way more practical to wait a few years before having a baby and pay off our loans, then to have our budget streched so tight that life and rasing a child would be very hard. (Keep in mind that the number one reason for couples fight is money.)
One thing to think about is will one of you stay home with the baby and if so, can you survive on one income? If both of you plan on working will you have to pay for daycare?
We are 11 months from paying off all of our loans, and it has been a long, hard road, but very much worth it. It has been so hard seeing everybody else being pregnant and having babies, but in the end I know that we made the right decision. And when we have met our finically goals, bringing a child into this world will just be that much more sweeter and enjoyable.