Results: Among 1260 neonates entered, the placentas of 527 had evidence of histologic chorioamnionitis and 733 did not. Those with histologic chorioamnionitis had a lower mean gestational age, lower birth weight, and higher rate of major neonatal morbidities than those without it. After adjusting for confounding variables, histologic chorioamnionitis independently associated with lower gestational age, lower birth weight, and neonatal death. Among neonates exposed to antenatal steroids who had histologic chorioamnionitis, there was a significantly lower incidence of low Apgar scores (18% compared with %, P < .001), respiratory distress syndrome (RDS) (% compared with %, P < .001), intraventricular hemorrhage and periventricular leukomalacia (% compared with %, P < .001), major brain lesions (% compared with %, P < .001), patent ductus arteriosus (% compared with %, P = .018), and neonatal death (% compared with %, P = .02), with no increase in rate of proven neonatal sepsis (% compared with 14%, P = .24).
As the condition is more prevalent in black women in the US and the UK, it has been suggested to be an explanation for the higher rate of preterm birth in these populations. It is opined that bacterial vaginosis before or during pregnancy may affect the decidual inflammatory response that leads to preterm birth. The condition known as aerobic vaginitis can be a serious risk factor for preterm labor; several previous studies failed to acknowledge the difference between aerobic vaginitis and bacterial vaginosis, which may explain some of the contradiction in the results. 
The responsible use of oxygen should also be promoted at all levels. Adequate monitoring is essential, especially in the premature infant <32 weeks gestation and <1 500g birth weight, as these infants are at an increased risk for retinopathy of prematurity (ROP), a leading cause of blindness in children. The second Benefits of Oxygen Saturation Targeting trial (BOOST II) recently reported that lower saturations of 85 - 89%, which reduce the risk of ROP, had a significantly higher rate of death than saturations of 91 - 95%. 9