With both my wife and I working, we have a combined income of round $225-$300k, depending on the year, which is higher than the vast majority of the population, and even for us it's hard. $50-$60k for full-time childcare. $10k into the college fund. Easily $10k-15k a year in healthcare, dentistry, etc, because somebody always needs tonsils out, knocks out a tooth, etc. Another $5k in school supplies, activities, and sports. Already I'm at $75-$90k/year for my three, and that's not even including food, clothes, and fun ... and you can't forget about the $10-$20k that it cost to bring each into the world.
Just to offer a contrasting view to any prospective parent reading the above, I find having kids to be totally affordable, on less income.
Try Christian health ministries. It is much cheaper than health insurance and they payed the entire bill for our 4 kids to be delivered. We also have found having one parent at home be a worthwhile investment in many ways. Cheers mate. I personally consider each of my children to have added to my wealth immeasurably.