Management of Twins
Mar 2012 – by T. Aeby, MD
While twins can be two-for-one bundles of joy, they also come with a significantly increased rate of complications, as compared to singleton pregnancies. Specific considerations are involved with antepartum management as well as plans for delivery.
A. Need for early ultrasound to
1. Determine chorionicity since monochorionic/diamniotic pregnancies have 10-15% risk of twin-to-twin transfusion syndrome while di/di and mo/mo have almost no chance.
2. Detect anomalies and syndromes given that twin pregnancies have a greater than 2-fold higher rate of aneuploidy.
3. Identify congenital heart defects, which occur at higher rates in IVF and monochorionic twins.
B. Preterm labor
1. Affects 60% of twin pregnancies.
2. FFN and cervical length measurements (using >25mm as a cut-off) perform equally well in identifying symptomatic patients at risk for preterm delivery (neither is useful in asymptomatic patients).
3. Home uterine monitoring, prophylactic tocolytics, bed rest and cerclages are not helpful in asymptomatic patients.
4. Steroids are effective and a single rescue dose, if given greater than 14 days after a full steroid course, is also effective.
C. Discordant growth
1. Defined as 15-25% discrepancy in EFW
2. Growth-restricted twins donít do any better than similar sized, growth-restricted singletons
3. Management needs to be individualized but is similar to management of a growth restricted singleton
4. Impact on both twins must be considered when contemplating delivery of a discordant set of twins
D. Intrauterine demise of one twin
1. Expectant management of the second twin is often appropriate because any insult to the surviving twin usually occurs shortly after the demise of the first twin, but before the death is detected.
2. Antepartum testing is appropriate
3. DIC is theoretically possible but quite rare
E. Mothers of twins are at greater risk of hypertensive disorders, HELLP, gestational diabetes, anemia, acute fatty liver, thromboembolic disease, PUPPPS, postpartum hemorrhage and death
F. Newborns are at greater risk of cerebral palsy, growth restriction, anomalies and handicaps
G. Timing of Delivery
1. Di/Di twins, uncomplicated 38 -40 weeks
2. Mono/Di, uncomplicated, 36-38 weeks
3. Mono-amniotic twins are very high-risk and should be hospitalized for monitoring at an early gestational age (24-26 weeks) and delivered by 32-34 weeks
4. Early delivery for obstetric complications only
5. Amniocentesis is generally not required since the medical complication is dictating the timing of delivery, not fetal lung maturity
H. Route of Delivery
1. Depends on presentation and estimated fetal weights
2. General agreement that twins should only labor in a setting that would allow immediate cesarean delivery if needed
3. A trial of labor is appropriate when the first twin is vertex
4. When the second twin presents in a non-cephalic fashion, the options for delivery of the second twin are external cephalic version, breech extraction or cesarean delivery. Outcome data seem to favor breech extraction as long as:
a. Gestational age is >28 weeks;
b. Estimated fetal weight >1500gms;
c. Discordance is < 20%; and
d. An obstetrician experienced in breech deliveries is present
5. Epidural anesthesia for labor and delivery is recommended
6. Trial of labor after cesarean delivery (TOLAC) appears to be safe