title: Fetal hyperechogenic bowel following intra-amniotic bleeding.
abstract: OBJECTIVE
  To test the hypothesis that increased echogenicity of the fetal bowel at second-trimester scans results from intra-amniotic bleeding.
  
  
  METHODS
  We studied 726 patients undergoing second-trimester amniocentesis for advanced maternal age. Three groups were identified according to the color of the amniotic fluid (AF) obtained: clear fluid, blood-stained fluid, and dark brown fluid. Two to 4 weeks after the amniocentesis, all patients had a targeted ultrasound examination for the detection of fetal structural anomalies and markers of chromosomal abnormalities, which included a survey of the fetal bowel. The incidence of hyperechogenic bowel in each group was compared by Fisher exact test. P < .05 was considered significant.
  
  
  RESULTS
  In 694 cases, the AF was clear (95%), in 20 blood-stained (3%), and in 12 dark brown (2%). Hyperechogenic bowel was detected in 14 fetuses with clear fluid (2%), in two with blood-stained fluid (10%), and in three with dark brown fluid (25%). Fetuses with proven intra-amniotic bleeding (ie, dark brown or blood-stained AF at amniocentesis) had a significantly higher incidence of hyperechogenic bowel compared to those with clear AF (five of 32 [15.6%] and 14 of 694 [2.0%], respectively; P < .001, 95% confidence interval for the difference in proportions 6.3-17.6%).
  
  
  CONCLUSIONS
  Our study demonstrates that intra-amniotic bleeding is associated with an increased incidence of fetal hyperechogenic bowel at second-trimester ultrasound scans. This sonographic phenomenon may be due to the presence of blood in the fetal bowel caused by fetal swallowing of bloody AF.
authors.affiliation: Centre for Fetal Care, Royal Postgraduate Medical School, Queen Charlotte's and Chelsea Hospital, London, United Kingdom.
authors.forename: W
authors.initials: W
authors.lastname: Sepulveda
authors.forename: J
authors.initials: J
authors.lastname: Hollingsworth
authors.forename: S
authors.initials: S
authors.lastname: Bower
authors.forename: J I
authors.initials: JI
authors.lastname: Vaughan
authors.forename: N M
authors.initials: NM
authors.lastname: Fisk
mesh_terms: D000649:Amniocentesis / Q000009:adverse effects; D000653:Amniotic Fluid; D005260:Female; D006470:Hemorrhage / Q000209:etiology*; D006801:Humans; D007231:Infant, Newborn; D007422:Intestines / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000209:etiology*; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D016216:Ultrasonography, Prenatal