[Foetomaternal transfusions after amniocentesis in early pregnancy - evaluation of 1,000 cases (author's transl)]

Abstract

The foetal haemoglobin (HbF) content was determined before and 2 hours after amniocentesis in 1,000 cases of amniocentesis conditioned by genetic indication (between the 15th and 20th pregnancy week). HbF-identification was effected according to the method of Kleinhauer and Betke. In primarily (before amniocentesis) negative HbF findings, HbF positive findings after amniocentesis were obtained in 7.2% of the patients. However, if the HbF-determinations were positive already before amniocentesis, a quantitative increase of HbF-cells in the maternal blood smear after amniocentesis was observed in 15.9% of the patients. Patients with punctures in the case of placenta of the anterior wall showed and increase in HbF values after amniocentesis in 12.2% of the cases, compared against 8.9% only in patients with posterior wall placenta, but these differences were statistically not significant. Amniocentesis under ultrasonic visual control caused a drop in the number of repeated amniocentesis trials to 20/500, aspiration of bloodstained amniotic fluid to 3.6% and HbF-cell positive blood smears after amniocentesis to 7%. (Free-hand-needle-technique: amniocentesis failures 42/500, amniotic fluid samples contaminated with blood in 9.6% of the cases and increases in HbF-values after amniocentesis in 12.6% of the cases). A total of 82 Rh-negative patients were given conventional anti-D-prophylaxis independent of the localisation of placenta. No sensitization was observed in any of the cases. No boosting was caused by early amniocentesis in cases where a positive anti-body finding had been established (3 cases to date).