[Correlation between cordocentesis performed during pregnancy and premature delivery]

Cordocentesis is a procedure used to obtain fetal blood sample or to perform an intrauterine therapy. The cordocentesis is performed to determine the blood group, blood cell counts, fetus karyotype, intrauterine infection, level of 17-OH progesterone and fetus renal secretion. Access to the umbilical vein is possible from the 16-18th week of gestation.

The aim of our study was to determine the impact of cordocentesis on the premature delivery.

Authors have analysed the course of gestation and delivery in all the cases with at least one cordocentesis carried out in the Department of Obstetrics in Gdańsk in 1991-2002. The group of 145 pregnant women was analysed. In this group 199 cordocenteses were performed. In 31 cases there was a premature delivery which was not a complication of cordocentesis. The duration of pregnancies in each group was compared to the control group--a total of 1657 patients who gave births in the Institute of Obstetrics and Gynecology in 1998. For statistical analysis of the results the T-Student test was used with the significance level p = 0.05.

The mean duration of pregnancy in the control group was 40 +/- 2.47 weeks (from 23 to 45), in the group of patients after cordocentesis--33.97 +/- 4.68 weeks (from 23 to 42)--no statistical difference was found. In the group of patients with lethal malformation of foetus the induction of delivery was performed in the 30.97 +/- 4.66 week of gestation (from 23rd to 41st)--statistical difference to the group of all patients after cordocentesis. In cases with only diagnostic cordocentesis the delivery took place in 36.85 +/- 2.60 weeks of gestation and in the group with fetal blood transfusions the mean duration of pregnancy was 35.36 +/- 3.72 weeks. The incidence of the premature deliveries in the control group was 7.18% and in the group of patients after cordocentesis--72.46%--there is significant difference between these two groups. The cesarean section was performed in the control group in 23.60% and in 36.23% in the group of patients with performed cordocentesis.

The intrauterine transfusions during cordocentesis do not influence the term of delivery. The term of delivery after the diagnostic and therapeutic cordocenteses does not statistically differ from the term of delivery in the control group. The cordocentesis (the result of blood tests) allows to determine the need of induction of delivery. It gives better prognosis for the newborn.