A new funipuncture technique: two-needle ultrasound- and needle biopsy-guided procedure.

A new technique is presented for funipuncture under ultrasound guidance using a biopsy guide and a 20/25-gauge needle combination. The 20-gauge needle was used for uterine entry and the 25-gauge needle for the actual cord puncture. The method was used for sampling fetal blood in 262 pregnancies with 264 fetuses (two sets of twins) between 17-39 weeks, at risk for beta-thalassemia, chromosomal disorders, TORCH infection, fetal hypoxia, and Rh-isoimmunization. Pure fetal blood was aspirated from 241 fetuses (91.3%), including the twins. The procedure lasted less than 5 minutes in 76.5% of the cases and less than 10 minutes in 90.1% of the cases. Intra-amniotic bleeding was seen in only 23.1% of the cases, and fetal bradycardia was not noted. Forty-four pregnancies were terminated after the diagnosis of genetic or infectious disease. Seven fetuses at risk for Rh-isoimmunization, found to be Rh-positive and anemic, were transfused immediately after blood sampling using the same needle. Of the 220 continuing pregnancies, there were 14 fetal losses (three before 28 weeks and 11 after 28 weeks or during the perinatal period). A probable etiology for the loss was found in 11 cases. These included one severely Rh-isoimmunized hydropic fetus who died in utero after transfusion at 26 weeks, one fetus who died in utero at 31 weeks following a car accident, and nine malformed newborns. The corrected rate for fetal losses probably related to the procedure was thus 0.9% before 28 weeks and 0.8% after 28 weeks. This new funipuncture technique seems to have several advantages over the freehand and/or biopsy-guided single-needle techniques.