It depends on the individual relationship, I think...though for most, that first two years is the time to really get to know each other and learn the fundamentals of working together, and kids can really complicate things. I've personally been with my husband two years now, and our daughter will be born within the next couple of weeks. In our case I think that while more time alone together might have been a good thing, having a baby now really isn't crippling. We know each other well, and both have kids from previous marriages -- his are older, mine will be 5 in December -- so children have been a factor since the beginning, and we've already become well-acquainted with each other's parenting styles. Parenting styles seem to be one of the biggest disagreements between a lot of couples who have kids early on in the relationship, and something that should probably be discussed extensively before having children.