Discolored amniotic fluid--results of prenatal diagnosis and clinical significance

7000 pregnancies were analysed after genetic amniocentesis in respect of the further course and results of prenatal diagnosis (observation period 1975-1988). In 3.1% (217 cases) samples of amniotic fluid were discoloured. Vaginal haemorrhages prior to amniocentesis were recorded with significantly higher incidence (18%) in patients with discoloured amniotic fluid than in a control group (n = 217) with normal colour of the amniotic fluid (4.6%) (p less than 0.001). Miscarriages and chromosome anomalies occurred more often in the study group (3.7%/2.8%, control group: 0.9%/1.8%, n.s.). The risk of miscarriages was increased in cases with sanguineous amniotic fluid if the amniotic fluid alpha-fetoprotein values were enhanced at the same time. Significant differences were observed in respect of the incidence of foetal malformations in patients with discoloured amniotic fluid (7.8%) and in the control group (2.3%) (p less than 0.01). Borderline or definitely pathological amniotic fluid AFP concentrations were found often if the amniotic fluid was discoloured (6.9%, control group 3.2%). If discoloured amniotic fluid was sampled, foetal malformations should be excluded sonographically. In 82% of all cases with discoloured amniotic fluid and foetal malformations pathological sonographic findings and/or enhanced MS-AFP values were recorded even prior to amniocentesis.