Breech presentation and delivery in singleton term pregnancies in Finland

The cesarean section rate is increasing worldwide and breech presentation is with approximately 17 % one of the major indications for elective cesarean sections. Cesarean section might be a life-saving procedure for mother and child during labor, but is also a major procedure with possible complications and adverse long-term effects for future pregnancies. Breech presentation occurs in 2-3 % of term pregnancies. The safety of vaginal breech delivery has been questioned for a long time, as a trial of vaginal breech labor is associated with an increased adverse short-term outcome. The study was designed to evaluate the potential pathophysiology of breech presentation itself, to look for unidentified risk factors associated with adverse perinatal outcome in vaginal breech deliveryand to investigate if a trial of vaginal labor at term with the fetus in breech position, is associated with adverse neurodevelopmental outcome in the children at the age of four. The breech presentation rate at term in Finland is 2.2 %. Breech presentation is compared with vertex presentation associated with a higher stillbirth rate Breech presentation is compared with vertex presentation associated with a higher stillbirth rate, fetal growth restriction, oligohydramnios, gestational diabetes, congenital fetal abnormalities and a previous cesarean section. The perinatal outcome in induced deliveries compared to spontaneous breech deliveries did not show differences. However, a trial of induced breech labor was associated with a higher intrapartum cesarean section rate compared to spontaneous breech labor. An active second delivery stage lasting less than 40 minutes protects from adverse perinatal outcome. A higher intrapartum cesarean delivery rate of at least 24 % was also associated with a lower rate of adverse outcome. Epidural anesthesia, instead, was associated with a higher risk for adverse neonatal outcome. The study results confirmed fetal growth restriction as a risk factor for adverse perinatal outcome in vaginal breech labor. In addition we found that oligohydramnios, a previous cesarean section, gestational diabetes, epidural anesthesia and nulliparity are associated with a higher risk for adverse peri- and neonatal outcome. The neurological development of children at the age of four years, which were born after a trial of vaginal labor with the fetus in breech presentation, compared to those born by elective cesarean section with the fetus in breech presentation. In conclusion our studies showed that breech presentation at term is more often associated with other clinical factors that are per se markers for possible adverse obstetric risks. We showed that an active second delivery stage lasting less than 40 minutes or a higher intrapartum cesarean section rate of at least 25 % have a protective influence on fetal outcome in a trial of vaginal labor with the fetus in breech presentation. Adverse neonatal outcome in vaginal breech delivery was associated with oligohydramnios, fetal growth restriction, gestational diabetes, previous cesarean delivery, epidural anesthesia and nulliparity. An induction of labor while the fetus is in breech presentation is feasible. There were no differences in the neurological development of children born after a trial of vaginal breech labor at term compared to children, who were born by elective cesarean section while the fetus was in breech presentation.