In about one-tenth of pregnancies in which the mother has a congenital bleeding disorder (CBD), recommended fetal precautionary measures may influence the mode of delivery, according to research published in the European Journal of Haematology.
CBDs, which include coagulation factor deficiencies, von Willebrand Disease (VWD), platelet function defects, and bleeding disorders of unknown cause, can make pregnancy management difficult. Risks of maternal bleeding and fetal hemmorhage persist, depending on the CBD subtype and mode of inheritance, which is not always well-characterized.
As CBDs in pregnant patients present a large number of variable complications, multidisciplinary teams of obstetricians, hematologists, anesthetists, and pediatricians are recommended to ensure optimal outcomes. Intrapartum precautions and fetal restrictions — including avoiding ventouse, midcavity forceps, fetal scalp electrode, and fetal blood sampling — are employed when there is significant risk of fetal hemmorhage.
Extensive restrictions during vaginal delivery are linked with a risk of requiring emergency Cesarean section, leading to debate about their use. For this study, researchers aimed to understand the effect of fetal restrictions imposed “due to CBD on maternal and neonatal outcomes, examining the influence on the rate of emergency [Cesarean section] or delivery related complications.”
All data were collected retrospectively, and were obtained from a cohort of patients with CBD treated at a hospital where fetal restrictions were more frequently used.
Overall, 76 patients were included in the final cohort, comprising 94 pregnancies; 20 patients were carriers of hemophilia, 28 had low von Willebrand Factor levels or VWD, 8 had other coagulation factor deficiencies, and 20 had a bleeding disorder of unknown etiology.
Of the 94 pregnancies, 83 (88.3%) had fetal precautions advised, while 11 (11.7%) did not. There was no significant difference between the groups in the numbers of nonlabor elective Cesarean section, emergency Cesarean section not in labor, or emergency Cesarean section in labor (6 [7.2%] with precautions advised vs 3 [27.3%] without; P =.07).
Among 63 patients who went into labor with fetal precautions, 6 (10%) underwent Cesarean section because of the precautions.
Primary postpartum haemorrhage was noted in 9 patients (12.2%) overall.
“This study is not of sufficient size to comment on maternal and foetal safety with different modes of delivery in different CBDs. It does show, however, that 10% of women who labour with foetal precautions in place are delivered by Caesarean section because of these restrictions. This is important information when counselling this group of women about mode of delivery,” concluded the investigators.
Lavin M, Horan M, Durand O’Connor A, et al. The impact of foetal restrictions on mode of delivery in women with inherited bleeding disorders [published online June 30, 2020]. Eur J Haematol. doi: 10.1111/ejh.13481