Table 3.

Infants born at the threshold of viability (<750 g) and neonatal mortality rate: Colorado, 1991–1996 vs 1997–2003

Birth weight (g)	1991–1996				1997–2003
	Live births	Neonatal deaths	NMR (%)	Survival rate (%)	Live births	Neonatal death	NMR (%)	Survival rate (%)
<300	75	71	94.7	5.3	186	181	97.3	2.7
300–399	130	115	88.5	11.5	204	189	92.6	7.4
400–499	160	139	86.9	13.1	267	216	80.9	19.1
<500	365	325	89.0	11.0	657	586	89.2	10.8
500–699	255	161	63.1	36.9	397	265	66.8	33.2
600–749	409	147	35.9	64.1	610	233	38.2	61.8
500–749	664	308	46.4	53.6	1007	498	49.5	50.5
<750	1029	633	61.5	38.5	1664	1084	65.1	34.9
⩾750	327 277	775	0.2	99.8	449 415	906	0.2	99.8

Abbreviation: NMR, neonatal mortality rate.