Abstract
Research question
Does fetal reduction of triplet pregnancies to singleton result in superior obstetric
and neonatal outcomes compared with triplets reduced to twins?
Design
A historical cohort study including 285 trichorionic and dichorionic triplet pregnancies
that underwent abdominal fetal reduction at 11–14 weeks in a single tertiary referral
centre. The study population comprised two groups: reduction to twins (n = 223) and singletons (n = 62). Main outcome measures were rates of pregnancy complications, preterm delivery
and neonatal outcomes. Non-parametric statistical methods were employed.
Results
Triplet pregnancies reduced to twins delivered earlier (36 versus 39 weeks, P < 0.001) with higher prevalence of Caesarean section (71.1% versus 32.2%, P < 0.001) compared with triplets reduced to singletons. Preterm delivery rates were
significantly higher in twins compared with singletons prior to 37 weeks (56.9% versus
13.6%, P < 0.001), 34 weeks (20.2% versus 3.4%, P = 0.002) and 32 weeks (9.6% versus 0%, P = 0.01). No significant difference was found in the rate of pregnancy loss before
24 weeks (1.3% in twins versus 4.8% in singletons, P = 0.12) or in the rate of intrauterine fetal death after 24 weeks (0.4% versus 0%,
P = 1.0). Both groups had comparable obstetrical complications and neonatal outcomes,
except for higher rates of neonatal intensive care unit admission in twins (31.9%
versus 6.8%, P < 0.001).
Conclusions
Reduction of triplets to singletons rather than twins resulted in superior obstetric
outcomes without increasing the procedure-related complications. However, because
the rate of extreme prematurity in pregnancies reduced to twins was low, the overall
outcome of those pregnancies was favourable. Therefore, the option of reduction to
singletons should be considered in cases where the risk of prematurity seems exceptionally
high.
Keywords
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Biography

Roni Zemet obtained her MD degree in 2013 as a graduate of The Hebrew University Hadassah Medical School in Jerusalem. She is completing her residency in the Department of Obstetrics and Gynecology at the Sheba Medical Center, Tel-Hashomer, Israel.
Key message
Reduction of triplet pregnancies to singletons rather than twins resulted in superior obstetric outcomes without increasing procedure-related complications. As the rate of extreme prematurity in pregnancies reduced to twins was low, the overall outcome of twins was favourable. Reduction to singletons should be considered for cases at high risk of prematurity.
Article info
Publication history
Published online: December 30, 2019
Accepted:
December 18,
2019
Received in revised form:
November 12,
2019
Received:
August 25,
2019
Declaration: The authors report no financial or commercial conflicts of interest.Identification
Copyright
© 2019 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.