Background and purpose: Amniocentesis is the most commonly used method for diagnosis of aneuploid and other genetic disorders of the fetus. Cautious should be taken when entering the amniocentesis needle to avoid entering the placenta. The purpose of this study was to investigate the consequences of needle transposition from the placenta during amniocentesis.
Materials and methods: In a cohort study, 1000 pregnant women candidates for amniocentesis were selected from Mashhad Perinatology Clinic, 2014-2016. A needle was inserted into the gestational sac and 20cc amniotic fluid was taken, using the ultrasound guidance. Passage or not passage of needle through the placenta was recorded and complications such as abortion, spotting, preterm labor, and rupture of membrane in each group were compared. Data analysis was done in SPSS applying Kolmogorov-Smirnov test, t-test, and Chi-square. The relative risk (RR) was also calculated.
Results: The mean age of participants was 33.4 years old (16-48 years of age). Spotting after amniocentesis was recorded in 1.4% nontransplacental amniocentesis and in 6.1% of transplacental amniocentesis (RR; 6.85, p=0.03). There was no significant relationship between needle passage through the placenta and other complications such as abortion, amnionitis, preterm labor, and amniotic fluid leakage following amniocentesis (p=0.08).
Conclusion: Current findings showed that transplacental amniocentesis increases the probability of spotting following amniocentesis.