Ryan - I don't think you're off on this subject at all! An infant too young could easily be injured (even if not visibly) while in a trailer. I do however think it can depend if you have a cheap trailer vs. a model with shock absorption features etc. Also if you are on a newly paved road vs. an older bumpy road. Continual shaking of a newborn on a bike ride is not something I'd recommend though.

Bob - Child carriers are an absolute MUST for mom and dad to have! They have those you've linked and also slings/mei tai are options as well. They're great for any time you need free hands, happy babies, and hiking of course. As far as putting it into a bike trailer for security.. I can't recommend that as they can be unsturdy, bulky, and may not fit in properly.

I've seen dozens of parents come to the downtown farmers market with infants in trailers under 12 months! I haven't done it myself, but have been commuting with my toddler for a almost a full year now. I'd stick with a Chariot for an infant and then Burley as a runner up for trailer choices.

Chariot makes a baby supporter for infants 3 -18 months.
http://www.chariotcarriers.com/english/html/accessories.php?accID=3

Burley makes a baby snuggler for infants 3-12 months.
http://www.burley.com/products/accessories/index.cfm

I'd chose a Britax car seat if I were to use one in a trailer.
http://www.britaxusa.com/safety/what-safe-reason.aspx
http://www.britaxusa.com/products/product_detail.aspx?ID=2

Any of the infants I've come across in trailers are in car seats. I do recommend waiting until your infant can sit up though which would occur sometime between 4-7 months. There is always public transportation and taking turns with dad staying home when going out. Trust me it goes by quick and there is always a way!

Congratulations Shea!

Krisha

--
Krisha Pessa
Youth Director
Salt Lake City Bicycle Collective
2312 S. West Temple
Salt Lake City, UT 84115
w: 801-328-2453
c: 801-931-0895
f: 801-466-3856
krisha@slcbikecollective.org
www.slcbikecollective.org