Introduction
Advanced maternal age and widely application of assisted reproductive
technologies have led to an increase in multiple gestations. Twins,
triplets, and higher-order multiple gestations now account for more than
3% of all live births.1 It is well known that
multiple gestation is associated with an increased risk of maternal
complications, as well as high perinatal morbidity and
mortality.2
Because triplet or higher-order multiple gestation are more likely to
develop these risks, several preventive strategies to limit the number
of fetuses are suggested. Elective single embryo transfer (eSET) and
multifetal pregnancy reduction (MFPR) are the recommended methods for
this purpose. In contrast to eSET which is a relatively acceptable
useful method,3,4 MFPR is a more complicated method in
clinical practice, involving a number of medical, economical,
psychological and ethical issues. Moreover, triplet pregnancies are more
common than quadruplet or higher-order pregnancies, making MFPR in
triplet pregnancy a more challenging subject.
As MFPR is not easily acceptable for infertile couples, more clear
evidences are required to recommend MFPR in triplet pregnancy. Most data
to advocate MFPR in triplet pregnancy were derived from comparison of
maternal and perinatal outcomes between twin and triplet pregnancies,
although direct comparison of outcomes between continuing triplets and
reduced twin from triplets is more desirable. To show the usefulness of
MFPR for triplet pregnancy, improved maternal and neonatal morbidity and
mortality in reduced twin from triplets should be demonstrated, but few
studies have been conducted in these points of view. Multifetal
reduction of a quadruplet or higher-order pregnancy to twins has been
advocated, with data showing that MFPR prolongs gestational age and
increases birthweight.5,6 Nonetheless, there are
conflicting data about whether pregnancies reduced from triplets to
twins fare better than expectantly managed triplet
pregnancies.7 Moreover, most of studies were conducted
several years or decades ago. Maternal and fetal morbidity and mortality
should be carefully assessed on the basis of contemporary data. To
clarify this issue, we conducted this study to compare maternal,
perinatal and long-term outcome of triplet pregnancies managed
expectantly with those reduced to twins.