Objective: The purpose of this study was to report our experience with placental bed biopsy with the use of forceps.
Study design: Placental bed biopsies were undertaken transcervically under ultrasound guidance in 313 women who underwent termination of pregnancy between 7 and 20 weeks of gestation, in 104 women with a missed abortion who underwent evacuation of retained products of conception between 7 and 21 weeks of gestation, and in 13 women after vaginal delivery. Placental bed biopsies were also undertaken in 139 women who underwent caesarean delivery. Frozen sections were immunostained with monoclonal antibodies to cytokeratin, factor VIII-related antigen, and desmin.
Results: Of the 417 cases attempted at <22 weeks, the placental bed was successfully sampled 281 women (67%); in 229 women (55%), at least one of the biopsy specimens contained a uterine spiral artery. Success was correlated with gestational age. Figures for the late cases that were sampled during caesarean delivery were 108 of 139 cases (78%) and 66 of 139 cases (47%) and after vaginal delivery were 11 of 13 cases (84%) and 6 of 13 cases (46%), respectively. The sampling procedure did not result in any significant morbidity.
Conclusion: With the use of forceps, uterine spiral arteries can be sampled successfully throughout pregnancy in approximately 50 % of cases.