A lot of the folks that are saying they don't regret having children are at the end of the spectrum with their kids being at or near adulthood. I would love to hear how they really felt when the kids were very young and their lives were turned upside down.
My wife and I have a 2 1/2 year old and a 4-month old. While we don't regret it for a minute, I can't say that I would automatically do it again if I went back in time. I love my kids more than anything and they have been incredible blessings, but I've aged more in these 3-years and have endured more stress than I ever thought possible.
In the first year of my son's life, he endured fully dislocated hips and spent the first 8-months of his life in a half-body cast. Shortly after, he had an epidural hematoma and had to have emergency brain surgery. He's perfectly fine now, but I wouldn't wish what we went through on my worst enemy.
The first 3-months of my daughter's life hasn't been much better. While she is perfectly healthy, she has a very sensitive stomach and basically screamed day and night for the first 12-weeks. Those 3-months were were worse than any period with my son.
Before kids, my wife and I both worked, both made 6-figures each. Now, she stays home and thankfully my income has continued to increase, but the financial stresses are still there. Even with great insurance, we have been hit with a minimum of 25k in medical bills every year. In 2011, we had over 50k in bills. Even with a great income, my savings is now depleted.
Bottom line, yes, kids are a blessing and a wonderful treat to get to see grow up and become their own little people. However, the stresses that come with the territory, especially if you don't get a perfectly healthy kid out of the gate, make you think twice before answering whether or not you would do it again.
Sorry for the long post, but I wanted to share the perspective of someone going through the experience currently. I'm sure in 10-15 years, I will have complete amnesia about the first few years of their lives and completely forget about how bad it was at various times. That's the beauty of the human spirit; it has the ability to make you remember the good times and forget the bad. In fact, the old adage about babies is that the reason people have a second or third kid is due to the fact that they forget just how horrible it was caring for an infant the first time around.