Comparison of pregnancy outcomes after second trimester amniocentesis between procedures performed by experts and non-experts

Objectives To compare the rate of fetal loss in pregnancy after second trimester amniocentesis between procedures performed by experts and non-experts and to assess other pregnancy complications as secondary outcomes. Methods A retrospective cohort study was performed on singleton pregnancies that underwent mid-trimester amniocenteses in a single institution. The fetal loss rates of procedures performed by experts and non-experts were collected and analyzed. Other adverse pregnancy outcomes were also examined. Results In total, 14,450 amniocenteses were performed during the study period. These included 11,357 (78.6%) procedures in the group expert operators and 3,093 (21.4%) procedures in the group non-expert operators. In the non-expert group, the fetal loss rate was slightly increased but not significantly (p=0.24).In addition, the higher number of spontaneous abortions was associated with blood-stained amniotic fluid sample (p<0.001; RR=9.28). Multiple needle insertions also increased in the non-expert group significantly. However, no difference in pregnancy outcomes was found between in single and multiple needle insertions. Conclusions The amniocentesis procedures performed by the non-experts was not increase the fetal loss rate. However, the other adverse pregnancy outcomes, including preterm birth, low birth weight and fetal growth restriction were significantly increased in the non-expert group.