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Twin pregnancy: Labor and delivery

Stephen T Chasen, MD
Frank A Chervenak, MD
Section Editor
Charles J Lockwood, MD, MHCM
Deputy Editor
Vanessa A Barss, MD, FACOG


Twin pregnancies are at increased risk of intrapartum complications, such as fetal heart rate abnormalities and complications related to malpresentation. This topic will review issues related to the delivery of twins, such as timing and route of delivery, fetal monitoring, maternal analgesia/anesthesia, and management of delivery. Antepartum assessment and neonatal management of these pregnancies, and monoamniotic twin pregnancy, are discussed separately. (See "Twin pregnancy: Prenatal issues" and "Monoamniotic twin pregnancy" and "Neonatal complications, outcome, and management of multiple births".)


Spontaneous or medically indicated preterm birth complicates over 50 percent of twin pregnancies, thus scheduling the timing of delivery is not subject to the discretion of the obstetrician in most cases [1]. In the absence of a spontaneous or medically indicated preterm delivery, the optimum time to deliver ongoing twin pregnancies depends on chorionicity and amnionicity.

Dichorionic twin pregnancy — For normal uncomplicated dichorionic/diamniotic twin pregnancies, we suggest elective delivery at 38+0 to 38+6 weeks of gestation, in agreement with recommendations from the American College of Obstetricians and Gynecologists (ACOG) [2]. Twin pregnancies complicated by fetal growth restriction are delivered earlier than 38 weeks, with the timing dependent on the clinical scenario.

There are no high-quality data from randomized trials on which to base a recommendation for the optimum timing of delivery of dichorionic/diamniotic twins. The optimal length of gestation appears to be shorter in twin than in singleton pregnancies. Epidemiological evidence suggests that the lowest rate of perinatal mortality (PNM) occurs at 37 to 39 weeks in twin pregnancies versus 39 to 41 weeks in singleton pregnancies [3-7]. Within this 37 to 39 week range, neonatal morbidity can be minimized by intervention at 38 to 39 weeks versus 37 to 38 weeks [7].

Although the authors of a 2016 systematic review of timing of delivery in uncomplicated dichorionic twin pregnancies recommended delivery at 37+0 to 37+6 weeks, we do not believe their data warrant a firm conclusion. The authors found that in dichorionic twins, the prospective risk of stillbirth was equivalent to the rate of neonatal death between 37+0 and 37+6 weeks, and the risk of stillbirth significantly exceeded the risk of neonatal death at 38+0 to 38+6 weeks and later [8]. Rates of neonatal morbidity, including respiratory distress syndrome, septicemia, and neonatal intensive care unit admission were all lower at later gestational ages. These data, however, are limited by the absence of data about quality of ultrasound examination, antepartum fetal monitoring, mode of delivery, and level of neonatal care. Without such data, it is difficult to assess the impact of a policy of delivering all dichorionic twins prior to 38 weeks of gestation. Therefore, we continue to recommend delivery of uncomplicated dichorionic twin pregnancies at 38+0 to 38+6 weeks.


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