Natalie, I dont know if you talked before marriage about children but if you did and he agreed to more than one than you may need to remind him of that. I am not a believer in only children, I know a ton of people that have them and it works great for them but I have always wanted my kids to have the oppurtunity to learn interaction that will create life skills that only comes from siblings. Since your DH is a science man you may want to look at some of the studies that have been done to show that the biggest influence on childrens ability to deal with conflict resolution comes from sibiling. There was one recently in Time magazine that was really good.
The other thing my DH and I discuss on a regular basis is that since I do 95% of the child care it is really up to me to decide what I can handle. The finacial stuff always works itself out and the fact is in our family that if my oldest was an only child she would have a TON of preassure on her because I have so many aspirations for my kids, now I have hopes that all of my dreams will be met for them, but it may be one of the other kids.

__________________