It is already recommended in the US that travel is minimised for premature babies and the new data suggests that full-term new borns (those born at or around 39 to 40 weeks) would also benefit from this.

BBC: Car seat danger to new babies

Cambodia's national children's welfare office says the number of foreign adoptions tripled in 1999, yet there is no shortage of destitute new-borns.

ECONOMIST: Cambodia

As for risk taking, the later borns, including middle and last borns, according to Adler are typically most game for new experiences.

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