"Unfortunately, at the age of 28, I'm afraid that I can't wait 7 more years to start a family."
Actually, there are lots of women who have children well into their thirties and even early forties now. Pregnancies in older women can be managed with a lot of success if you choose the right OBGYN. The risks for complications and birth defects do increase (but so does our ability to manage problems pre-natally though amniocentesis, etc.), but you also have to consider what quality of life you are going to have for you and your baby.
Start asking around, and you will hear about lots of women who have healthy first babies at 38 yrs+. I myself know a number of women with such stories.
I am 33 and will be an MS-1 next year and really hope you are wrong about 35 being the cutoff for being "too late" to have kids, because I can't imagine trying to have a child in medical school (I think it is a different situation for male medical students, at least the time from conception to birth!). We are going to aim for my second year of residency. At the hospital I worked in, there were a number of pregant second-year residents.
If I can be philosophical for a moment....
ultimately, it seems to me that life is a huge swap-meet where we trade one thing we value for another thing we value more. Time for money, a town we like living in for a better job, a less demanding job for more time with family, etc...You just have to arrive at a deal that seems fair for you to get as much of what you want from life as you can.
Good luck!