Can you point me to this research? Thanks!
Our Babies, Ourselves by Meredith Small presents anthropological data, like the fact that the USA is about the only country in the world where parents do not sleep with their infants, and other data in defense of cospleeping. She doesn't present much biomedical research type stuff though if that's what you're looking for.
dr. james mckenna is considered "the" expert on mother-baby sleep and is a huge advocate of co-sleeping based on numerous studies he has conducted at his sleep lab (www.nd.edu/~jmckenn1/lab/
also look at sept/oct 2002 issue of mothering
Glad someone gave you Prof. McKenna's website.
Here is the Gently to Sleep Resource Page
It has links to lots of pro-articles online. Not exactly what you may be looking for, but it's a great resource.
THREE IN A BED by Deborah Jackson (2000?) is an awesome book. It has much more scientific info (that's where I learned of Prof. McKenna's work) on the benefits of co-sleeping.
Here's Dr. Sears' co-sleeping page:http://www.askdrsears.com/html/7/T071000.asp
Deborah Jackson has a few books - Three in a Bed is probably most relevant but Baby Wisdom also has some information in it. Also Nightime Parenting by Dr Sears.