The primary concern with<unk>  is inadequate blood supply, and thus oxygen, to the baby if the<unk>  becomes compressed. The<unk>  can become compressed either due to mechanical pressure (usually from the presenting fetal part) or from sudden contraction of the vessels due to decreased temperatures in the vagina in comparison to the uterus. This can lead to death of the baby or other complications. Historically, the rate of fetal death in the setting of<unk><unk>  has been as high 40%. However, these estimates occurred in the context of home or births outside of the hospital. When considering<unk><unk> s that have occurred in inpatient labor and delivery settings, the rate drops to as low as 0-3%, though the mortality rate remains higher than for babies without<unk><unk> . The reduction in mortality for hospital births is likely due to the ready availability of immediate cesarean section. Many other fetal outcomes have been studied, including Apgar score (a quick assessment of a newborn's health status) at 5 minutes and length of hospitalization after delivery. While both measures are worse for newborns delivered after<unk><unk> , it is unclear what effect this has in the long-term. Relatively large studies that have tried to quantify long-term effects of<unk><unk>  on children found that less than 1% (1 in 120 studied) suffered a major neurologic handicap, and less than 1% (110 in 16,675) had diagnosed cerebral palsy.
Umbilical cord prolapse
Placental abruption
Shoulder dystocia
Retained placenta
Persistent cloaca
Neonatal sepsis
Cephalopelvic disproportion
Omphalitis of newborn