P18.15: Chorionic Villus Sampling in Assisted Conception Versus Spontaneously Conceived Twins

This study evaluates the impact of chorionic villus sampling (CVS) in twins conceived with assisted reproduction technology (ART) versus spontaneously conceived (Sp) twins regarding obstetric outcome. Case control study of 162 consecutive twin pregnancies that underwent CVS at a single center (Alexandra hospital, Athens, Greece). From 01.01.2000 to 30.6.2013 we recruited 32 ART and 130 Sp twin pregnancies. Patients having undergone multifetal reduction or chorionic villus sampling and those with fetal anatomic or chromosomal anomalies, discordant growth, death, or a monoamniotic sac detected at ultrasonography were excluded. The mean maternal age was not significantly different between the two groups. The fetal loss rate was also similar (6.3 vs 4.2% for the ART and Sp twins, respectively). The admissions to NICU were higher in the ART (29.7%) than in the Sp group (9.2%) (p < 0.001). The proportion of neonatal deaths was not significantly different between the two groups and was equal to 3.1% for ART twins group and 0.4% for the spontaneous twins group. Delivery before the 28 week was more frequent in the ART group compared to the spontaneous twins group (18.8% vs 1.5%, p = 0.001). The preterm delivery rate before 37 weeks was similar in the two groups (50% vs. 47.7%). The mean birthweight for the ART group was 2162 g (SD = 750 g), and for the spontaneous twins group was 2501g (SD = 485 g), (p = 0.004). First trimester CVS in ART and Sp twins carries a similar fetal loss rate and has the same impact on perinatal outcome.