We don't see many methadone mothers in our hospital because the methadone program for pregnant women in our area is located in a hospital across town. Most of the drug using moms we see are cocaine users. Their kids don't have as bad withdrawal as babies whose mothers used opiates such as heroin or methadone. There is some debate about whether cocaine harms the developing fetus. I haven't exhaustively studied the subject in the last couple of years, but I think that fetuses are relatively unscathed by intrauterine cocaine exposure. When cocaine became the popular drug in the late 80's and early 90's, there were some gloom and doom articles in the popular press saying we would have an epidemic of "crack" babies who would all reach kindergarten at the same time and need special education, putting an unbearable strain on our educational system. That hasn't happened, a testimony to the incredible resilience of the fetus and newborn. By the way, I don't allow residents and students in our NICU to use the term "crack" babies, a derogatory term that pegs them as losers before they even have a chance.
I like to ask the residents, "What is the worst common drug of abuse you can take in pregnancy, in terms of harming the fetus?" Some of them get it right, even though it's a bit of a trick question. The answer is alcohol, the only legal drug of the bunch. Alcohol causes growth and brain retardation and mental deficiency. If you're looking for a good long term outcome, give me a baby of a heroin or cocaine addict any day over that of an alcoholic mom.
In closing, I'd just like to point out a group of people who are probably especially frustrated with drug using moms, and that group is the infertile nurses who work in the NICU. We have two such nurses in our NICU now, both in their mid to late thirties, who have been struggling to have a baby for years. It must drive them crazy to see moms in their early twenties with 4 or 5 kids, and drug using moms with 8 or 9 kids, all dropping babies like rabbits, when they can't even have a single child. My heart goes out to them.