Originally Posted by
zansu
Stroller frames should not replace a stroller for long periods. Carseats are for use in the car. Frames are fine for in and out errands, but long periods of time confined to an infanct carseat can cause intestinal and respiratory problems, as well as cranial deformities.
I'm not an expert (except wrt cranial deformities), but my searches of the literature suggest that the respiratory issues are really only significant for very small infants (and preemies).
http://www.ncbi.nlm.nih.gov/entrez/q...m_uid=16882803
I can't find any referrences related to any intestinal problems.
Cranial molding is related to any supine positioning, whether in a car seat or elsewhere. This is not really a significant health problem, or anything with any real long-term consequences.
http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum