Table 3.

Duration of the HHE.

Duration (min)	n/N*	Level
<1	2/12***	1 and 2
1-<2	1/12	1
2 -<3	1/12	1
4-<5	3/12	1 (2) and 2(1)
9-<10	3/12	1 (2) and 2 (1)
14-<15	1/12	I
59–60	1/12	3

^*n/N: number of events/number of cases

^**One out of the 2 infants presented hyporeactivity for 12 hours, but hypotonia and pallor immediately resolved.