Survival Rate of Extremely Low Birth Weight Infants and Its Risk Factors: Case-Control Study in Japan

Table 3

Results of univariable and multivariable logistic regression analysis in terms of risk factors for neonatal deaths in extremely low birth weight infants.

	Univariable	Multivariable
Clinical chorioamnionitis	0.81 [0.61, 1.06]	0.88 [0.51, 1.52]
Premature rupture of the membranes	0.67 [0.54, 0.85]	0.81 [0.51, 1.30]
Placenta previa	0.94 [0.53, 1.64]	1.10 [0.34, 3.54]
Fetal growth restriction	1.00 [0.83, 1.22]	1.01 [0.85, 1.29]
Oligohydramnios	0.86 [0.65, 1.15]	1.36 [0.29, 4.29]
Placental abruption	1.91 [1.46, 2.51] *	2.50 [1.24, 5.03] *
Antenatal steroid	0.29 [0.19, 0.42] *	0.41 [0.22, 0.75] *
Nonvertex presentation	1.55 [1.29, 1.86] *	1.81 [1.21, 2.71] *
Nonreassuring fetal status	0.96 [0.77, 1.19]	0.82 [0.54, 1.24]
Gestational week at delivery	0.80 [0.76, 0.85] *	0.97 [0.87, 1.08]
Vaginal delivery	2.99 [2.48, 3.62] *	1.56 [1.00, 2.43] *
Male	0.86 [0.72, 1.04]	0.88 [0.59, 1.30]
Birth weight (100 grams)	0.994 [0.993, 0.995] *	0.996 [0.995, 0.998] *
Apgar score at 5 minutes	0.51 [0.48–0.55] *	0.56 [0.52–0.61] *

Values are presented as odds ratios [95% confidence intervals]. *Significant factors in predicting neonatal death. Underlines indicate significant data and bold indicates significant contributing factors for neonatal death.