Echogenic particles in the amniotic fluid of term low-risk pregnant women: does it have a clinical significance?

J Obstet Gynaecol. 2021 Oct;41(7):1048-1052. doi: 10.1080/01443615.2020.1834520. Epub 2021 Jan 11.

Abstract

In this study, we aimed to analyse the clinical features of the third-trimester pregnant women, with echogenic amniotic fluid and to compare their obstetric and neonatal outcomes with pregnant women with normal amniotic fluid echogenicity. This case-control study was conducted in a tertiary antenatal care centre. A total of 560 term (37-42 weeks of gestation) singleton women; 280 with echogenic particles in amniotic fluid and 280 with clear amniotic fluid, who delivered within 24 h after the ultrasound scan were evaluated. The women in the two groups were similar in terms of age, parity, body mass index, foetal birth weight, and gestational age. More patients in the particulate amnion group had lower Apgar scores (<7) in 1st and 5th minutes than controls (p = .006, p = .031 respectively) however the rate of admission to neonatal intensive care was similar. Vernix stained amniotic fluid was more common in the study group (48.8%, p = .031), the rate of meconium-stained amniotic fluid was similar in the study and control groups (9.6-9.2%, p = .881). The primary caesarean section rate was higher in women with particulate amnion (18.4%, p = .037). Echogenic particles in the amniotic fluid in the third trimester could not be attributed to meconium, however, higher rates of primary caesarean section may require further attention.IMPACT STATEMENTWhat is already known on this subject? Previous studies showed that high-density intra-amniotic particles were possibly related to vernix caseosa, intra-amniotic bleeding, and meconium. The number of study groups in these studies was also limited.What do the results of this study add? Additional to other previous studies, we found an increased rate of intra-amniotic echogenic particles in male foetuses.What are the implications of these findings for clinical practice and/or further research? The presence of echogenic particles on ultrasound was not related to increased risk for the presence of meconium. Significantly more neonates born to mothers with intra-amniotic echogenic particles tended to have lower Apgar scores (<7), however, this significant difference did not affect the need for NICU admission. The presence of echogenic particles in the amniotic fluid of the third-trimester pregnant women could not be attributed to meconium and adverse perinatal outcomes, however, the higher rates of primary caesarean section may require further attention.

Keywords: Meconium; amniotic fluid; amniotic fluid sludge; vernix caseosa.

MeSH terms

  • Adult
  • Amnion / diagnostic imaging
  • Amniotic Fluid / chemistry*
  • Amniotic Fluid / diagnostic imaging*
  • Apgar Score
  • Case-Control Studies
  • Cesarean Section / statistics & numerical data
  • Female
  • Humans
  • Infant, Newborn
  • Meconium / chemistry
  • Meconium / diagnostic imaging
  • Particulate Matter / analysis*
  • Pregnancy
  • Pregnancy Outcome
  • Pregnancy Trimester, Third / metabolism
  • Ultrasonography, Prenatal*
  • Vernix Caseosa / chemistry
  • Vernix Caseosa / diagnostic imaging

Substances

  • Particulate Matter