Optimal Time to Conceive: Considerations for Aspiring Parents

Question
I am a 31 yr old female , happily married for 3 yrs , both me and my husband are foreign MDS, now studying for USMLE. We live in texas. We don't have any health insurance, My husband is 35 yrs old. We would love to have babies.  I don't have any health problem besides h/o UTI once and family h/o diabetes and heart disease. I know my biological clock is ticking .But we want to wait till I finish my exams and residency (3 yrs). Because i heard that I can't be pregnant during my residency since it's too hard. So I am afraid i'll have to wait another 4-5 yrs.Then i'll be 35. Will it be risky for us to wait that long? We were considering our financial state and our carrier, but should we worry about my biological clock? I am in deep confusion, Please give us some advise! in this era of technological advancement can we wait till we take care of other things in life? Or should we start our family now? I need your help. Please give me some hope.

Answer
There are many women who wait until they are established in their careers before starting a family. I have several patients who are in their 40s and are having their first child. As I'm sure you know, as you approach 35 years of age and older, you risk for chromosomal abnormalities increases logarithmically. At the age of 30, the risk of Down's syndrome is 1:2700. At the age of 35, the risk of 1:350. At the age of 40, it is 1:100. You certainly would have an amniocentesis to test for chromosomal abnormalities and see the karyotype of the fetus. Then the decision would be yours. Other than that, there should be  no problems in waiting. The oldest patient I had delivered was 48 years old having her first child, and she did beautifully. Good Luck to you both.