That's the problem. Pre-school care. Hiring someone to care for your baby while you work.
Working women cannot make enough to pay for the costs of a baby, of the health care, of the child care, transportation and everything else they need nowadays.
And then there is the dream of a home and a college education for your kids. Raising a child, I have heard a young mother say, is estimated to cost around a million dollars over a lifetime. I assume that part of the cost is in the loss that a couple experiences due to the fact that one parent will miss work and receive fewer promotions at work because of the demands of parenting like taking a baby to the doctor, etc.
Employers don't offer much support or understanding for young parents who need extra time off for their children.
It's partly the costs of a child and partly the fear of losing their jobs that makes young people hesitate to have another baby.