Author: David Douglas
Twins tend to do better if born vaginally rather than by cesarean section, researchers report in a February 4th online paper in BJOG. But regardless of delivery mode, the first-born twin is less likely to suffer complications than the twin born second.
As Dr. A. Cristina Rossi told Reuters Health by email, “My review shows that the first twin is less likely to experience adverse outcomes compared with the second co-twin. Vaginal delivery seems to be safer for the first twin than cesarean section.”
Dr. Rossi of San Giacomo Hospital, Monopoli, Bari, Italy, and colleagues conducted a systematic review and meta-analysis involving 18 studies, 12 of which reported neonatal outcomes for both twins. In all studies, both twins were alive during labor and outcomes were stratified for birth order and presentation as well as planned and actual delivery mode.
More than 39,000 pairs of twins were involved. Neonatal morbidity was lower in the first than the second twin (3.0% versus 4.6%). This was also true of mortality (0.35% versus 0.6%). In either twin, there were no differences between vertex and non-vertex and attempted vaginal delivery versus planned cesarean section.
In the first twin, neonatal morbidity was lower after vaginal delivery than cesarean section (1.1% versus 2.1%). When the first twin underwent vaginal delivery and the co-twin underwent cesarean section (combined delivery), morbidity was significantly higher in the co-twin (19.8%) than was the case for vaginal delivery (9%) or cesarean delivery of both newborns (7.2%).
“In the absence of more definitive data, our systematic review suggests that an attempt at vaginal delivery should be considered in twin pregnancies,” say the investigators.
“With regard to the second twin, no differences are noted between cesarean section and vaginal delivery. Therefore, when the twins are both in vertex presentation, vaginal delivery can be attempted,” added Dr. Rossi. “If there is a vertex presentation of the first twin and nonvertex presentation of the second, women should be advised that trial of labor may be a safe option in the absence of risk factors for combined delivery.”
“However, predicting combined delivery in the antenatal period can be very difficult,” she concluded.