Optimal timing of fetal reduction from twins to singleton: earlier the better or later the better?

Abstract

What are the novel findings of this work? Compared with late first-trimester reduction of twins, second-trimester reduction is associated with an increased rate of prematurity and adverse neonatal outcome, without increasing procedure-related complications. What are the clinical implications of this work? Technological advances in sonographic diagnosis and more frequent use of chorionic villus sampling have enabled earlier detection of fetal anomalies. Therefore, efforts should be made to complete early fetal assessment in order to allow fetal reduction during the first trimester.

International Society for Prenatal Diagnosis Position Statement: cell free (cf)DNA screening for Down syndrome in multiple pregnancies

“…There are various procedures that can be used depending on the provider's preference, the gestational age, and zygosity. A recent report 36 of one tertiary referral center's experience with dichorionic diamniotic twin reductions to singleton reductions compares outcomes between procedures performed in the late first trimester (12-14 weeks) with those performed in the early second trimester (16-20 weeks). The earlier reductions (N=172) were often due to patient's request or abnormal ultrasound findings while the latter group (N=76) were mainly due to structural or genetic abnormalities.…”

Ten reasons why we should not abandon a detailed first trimester anomaly scan

“…Zemet al examined the outcome of selective terminations in dichorionic twin pregnancies between 15 and 23 weeks. 28 % of the healthy co-twins were born preterm and 12.0 % before 34 weeks, respectively [54] In contrast, selective terminations carried out between 11 and 14 weeks resulted in a preterm delivery rate of 14 % and only 1,8 % of the co-twins were born before 34 weeks' gestation.…”

“…Unter den verbliebenen Zwillingen waren 28 % Frühgeburten, und 12,0 % wurden vor der 34. SSW geboren [54]. Bei selektiven Abbrüchen zwischen der 11 und 14Schwangerschaftswochen betrug dagegen die Frühgeburtenrate 14 % und nur 1,8 % der Schwangerschaften kamen vor der 34.…”

Believing that transferring more embryos will result in increased pregnancy rates: a flawed concept: a SWOT analysis

“…Rates of prematurity and cerebral palsy are elevated in twins as compared to singleton pregnancies [16][17][18]. The problem with multiple pregnancies remains the higher risk of complications, both maternal and fetal/neonatal [17][18][19]. These complications include higher rates of miscarriage including late second trimester miscarriages, higher rates of preterm delivery, admission to the neonatal intensive care unit, cesarean section, fetal/neonatal death, preeclampsia, gestational diabetes [17][18][19].…”

“…The problem with multiple pregnancies remains the higher risk of complications, both maternal and fetal/neonatal [17][18][19]. These complications include higher rates of miscarriage including late second trimester miscarriages, higher rates of preterm delivery, admission to the neonatal intensive care unit, cesarean section, fetal/neonatal death, preeclampsia, gestational diabetes [17][18][19]. There are many situations where a single embryo transfer makes more sense than multiple embryo transfer and would not be debated.…”