Assisted reproductive technologies: an additional risk factor for severe postpartum haemorrhage

Several high-income countries have reported increases in severe postpartum haemorrhage (Knight et al. BMC Pregnancy Childbirth 2009;9:55), although the factors underlying the increase remain unclear. This rise in severe postpartum haemorrhage is cause for concern; it cannot be dismissed as being an artefact of increased vigilance and closer monitoring of blood loss, as objective markers of severity such as blood transfusion, hysterectomy and other invasive procedures to control blood loss have increased concurrently. The study by Nyfløt et al., which shows an increased risk of severe postpartum haemorrhage associated with assisted reproductive technologies (ART) adds a new dimension to the ongoing discussion regarding temporal trends in severe postpartum haemorrhage. Whereas infant outcomes such as preterm birth and low birthweight have been the focus of numerous studies on ART, maternal complications have received less attention. Nyfløt et al. assessed several important determinants of severe postpartum haemorrhage including body mass index, birthweight, mode of delivery, use of anti-coagulation therapy and labour augmentation and induction. They reported a modest relationship between ART and severe postpartum haemorrhage among singleton deliveries (OR 1.58; 95% CI 1.12–2.24), and a seven-fold increased risk following delivery of multi-fetal pregnancies. It is not clear whether the mechanism underlying the demonstrated relation between ART and severe postpartum haemorrhage is related to a maternal health condition associated with reduced fertility or some aspect of ART itself. The authors’ hypothesis regarding a potential effect of ART on placentation is supported by a systematic review which reported a higher risk for placenta-mediated complications such as stillbirth (OR 2.55; 95% CI 1.78–3.64), small-for- gestational age (OR 1.6; 95% CI 1.3–2.0), pre-eclampsia (OR 1.55; 95% CI 1.23–1.95), and placenta praevia (OR 2.87; 95% CI 1.54–5.37) among singleton deliveries following in vitro fertilistion (Jackson et al. Obstet Gynecol 2004;103;551–63). In addition, both placenta accreta and placental abruption have been associated with in vitro fertilization (IVF) and IVF/intracytoplasmic sperm injection (ICSI) (SOGC. J Obstet Gynaecol Can 2014;36;64–83). The combined and synergistic effect of placental problems due to multi-fetal pregnancy and ART potentially explain the large increased risk of severe postpartum haemorrhage among multiple pregnancies. However, it is not clear whether the multi-fetal pregnancies without ART in the Nyfløt et al. study were spontaneously conceived (or received other non-IVF methods), and clarifying the role of different technologies in the aetiology of severe postpartum haemorrhage is important. Given the increased risk of severe postpartum haemorrhage associated with ART demonstrated in this study, as well as the increased risk of placenta praevia and placenta accreta reported in previous studies, clinicians should consider ART, specifically in pregnancies conceived by IVF or IVF/ICSI, a risk factor for severe postpartum haemorrhage. This is especially important in cases of multi-fetal pregnancy following ART where the risks of severe haemorrhage are substantially higher. On the other hand, the contribution of ART to the temporal increase in severe postpartum haemorrhage in high income countries requires further study. None declared. Completed disclosure of interests form available to view online as supporting information. © 2017 Royal College of Obstetricians and Gynaecologists Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.