Exactly how the differences in bacteria might make vaginally born babies less prone to allergies and asthma isn't yet clear, but it does point to a difference that researchers can look at going forward.

VOA: standard.2010.06.30

No significant height differences were found between the California boys born in December and controls, results showed.

WSJ: Exercise in Short Bursts Is Effective

The results confirm those of previous studies that found higher rates of asthma among American children compared with kids from other countries, and investigators have also reported similar differences in allergic diseases between immigrants and native-born citizens in Italy, Israel and Australia.

CNN: American kids have higher allergy risk

The differences persist in the job market, even between migrants and German-born citizens with similar education.

ECONOMIST: Minorities in Germany