This NYTimes article from late last year examines the number of adoptions in our current tough economy. NY Agencies had expected an influx of children placed for adoption, thinking that higher poverty rates are often correlated with higher birth rates (I find this logic problematic--more on that later) and more relinquishments due to financial strain. But it didn't happen. Rates actually decreased.
Some speculate that birth mothers are going through private, non-agency channels with individual couples, because often they'll receive more $ for medical expenses, etc. (But then again, I'm thinking, maybe there are fewer adoptive families able to pay high prices for private adoption.)
One expert's guess: Maybe moms are just trying to keep their babies...single motherhood is becoming much more accepted anyway.
It's anybody's guess. It goes to show that you can't predict these things, and that there is never just one single factor involved in complex human decisions and transactions in regard to family, unexpected pregnancies, and adoption. Maybe it's sad news for hopeful adoptive parents, that there may be fewer children on the market. But, I'd say it's a good thing that there aren't more kids being put up for adoption. Hopefully struggling mothers are getting more help, and children can stay in their families. This is, after all, the best outcome.