The impact of changes in preterm birth among twins on stillbirth and infant mortality in the United States

Abstract

OBJECTIVE To examine trends for preterm births, stillbirths, neonatal and infant deaths in twin births by gestational age and birth weight categories, as well as trends in induction of labor and cesarean delivery during 1995–2006. STUDY DESIGN A trend analysis was performed on data derived from the National Centers for Health Statistics’ Vital Statistics Data files (1995–2006). The primary outcomes examined were preterm birth, stillbirth, neonatal and infant mortality. RESULT During the study period, rates of labor induction among twins decreased by 8% and rates of cesarean delivery increased by 35%. Concurrently, the preterm birth rate increased by 13% from 54% in 1995–96 to 61% in 2005–06. The overall stillbirth rate, and neonatal and infant death rates decreased during the same period by 21% (95% confidence interval (CI): 18–25%), 13% (95% CI: 9–16%) and 12% (95% CI: 8–15%), respectively. There were significant reductions in neonatal death rates related to respiratory distress syndrome (RDS; 48%, 95% CI: 41–54%) and congenital anomalies (25%, 95% CI: 16–33%) during the study period. Reductions in post-neonatal infant mortality were mainly in RDS (88%) and sudden infant death syndrome (26%). Mortality rates among infants born by either induction of labor or cesarean delivery fell during the study period and remained much lower than the overall infant mortality rate. CONCLUSION The findings of this study suggest that during 1995–2006 there was an increase in preterm birth rates and a decrease in labor inductions with a sharp decline in stillbirth, neonatal and infant mortality rates.

Improved Perinatal Mortality in Twins—Changing Practice and Technologies

“…9 While the twins have an established increased risk of perinatal morbidity and mortality, 1 improvements in monitoring and technologies associated with management of twin pregnancy and prematurity, 10,11 as well as altered practices regarding antenatal management and delivery practices have led to improvements in rates of stillbirth and neonatal mortality. 12 In view of new evidence and attitudes to management of twin pregnancies, we sought to examine changing rates of perinatal mortality. We also sought to examine in detail the characteristics of twin mortalities across the 17-year period from 1996 to 2012.…”

The Effect of Twin Birth on Neonatal and Infant Mortality Rates: A Systematic Review

“…15 In a study carried out during1995-1996 and 2005-2006, the statistics were compared with each other. 8 In the United States, because of advanced medical and health services, other causes have also been studied. The causes of twin death can be attributed to factors such as congenital malformations, complications of pregnancy, respiratory distress syndrome, spinal and neurological complications, intrauterine hypoxia, infection and other causes.…”

“…complications of placenta, hypoxia in the uterus and congenital anomalies increased. 8 However, in developing countries such as South Africa, some communicable diseases like tetanus, malaria, gastroenteritis, blood infections, malnutrition and LBW could still be the leading causes of death. In these countries, there is no systematic study of the causes due to the poor levels of medical and health services.…”

“…On the other hand, because of the use of cesarean section for delivery, the number of the premature births has been increased, which may in turn increase the number of twin deaths. 8 Furthermore, the study of trends in developed countries showed that women who have lower socioeconomic status and lived in deprived areas, were less likely to have twin pregnancies, especially women over the age of 35. 13 Ultimately, this study showed that the mortality rates in twins would be greater than in singletons, with higher rates among boys than girls.…”

“…7 The increase in multiple pregnancies may be accompanied by an enhancement of preterm birth; moreover, women who have had the multiple births could prefer to choose cesarean section more than others. 8 In addition, one of the reasons for twin death could be the premature birth as well as limited embryonic growth in the mother's uterus. 9 Twins may account for about 10% of all prenatal mortality, which might be exclusively due to premature births.…”