Women with von Willebrand disease (VWD) experience many obstetric and gynecologic challenges, including higher levels of von Willebrand factor (VWF) in pregnancy, Romina Brignardello-Petersen, PhD, of McMaster University, Hamilton, Ont., and colleagues wrote.
The American Society of Hematology, the International Society on Thrombosis and Haemostasis, the National Hemophilia Foundation, and the World Federation of Hemophilia convened a working group in 2017 to address updated guidelines on VWD with a focus on women, the researchers said.
In an article published in Blood Advances, the researchers described the evidence from three systematic reviews conducted to inform three recommendations for the guidelines: first-line management of heavy menstrual bleeding (HMB), treatment of women requiring or desiring neuraxial analgesia, and management of postpartum hemorrhage. The authors identified studies published through October 2019.
The first systematic review of first-line therapies for HMB included five case series, one retrospective cohort study, and one randomized controlled trial. In the randomized controlled trial of 232 patients, low-certainty evidence suggested less reduction of blood loss with desmopressin, compared with tranexamic acid (TxA), with no significant differences in side effects. Very-low-certainty evidence from an observational study also supported lower effectiveness of desmopressin versus hormonal therapy. Finally, the case series showed very-low-certainty evidence for the comparative effectiveness of hormonal therapy delivered via a levonorgestrel-releasing intrauterine system (LNG-IUS) and other therapies for HMB control.
The second systematic review compared VWF levels in women who received neuraxial anesthesia during labor.
The review included five case series that described outcomes of women with VWF levels greater than 0.50 IU/mL; however, the studies did not describe outcomes according to VWF levels and did not cite the proportion of women with VWF levels greater than 1.50 IU/mL. Consequently, the evidence for the effects of increasing VWF levels was very low certainty, the authors said. In a meta-analysis, the proportion of anesthesia complications in these women was 6% (very low certainty). The complications included hypotension, accidental dural puncture, inadequate analgesia, bloody tap with no further complications, and failed block requiring general anesthesia.
The third systemic review included two retrospective cohort studies on the use of TxA during the postpartum period. In these studies, the authors found very-low-certainty evidence that TxA reduced the risk of severe primary postpartum hemorrhage, primary postpartum hemorrhage, and secondary postpartum hemorrhage (risk ratios, 0.36, 0.25, and 0.42, respectively). The effects of TxA on blood transfusions, vaginal hematoma, blood loss, and thrombotic complications also showed very-low-certainty evidence.
The currently available evidence for treatment options in women with VWD remains very low certainty, the researchers wrote in their discussion. “Because hormonal therapy is effective in controlling HMB (based on data from women without bleeding disorders), we believe the most effective strategy to be hormonal therapy with a LNG-IUS or combined oral contraceptives, followed by TxA and desmopressin.”
The study findings were limited by several factors including scarce evidence, the risk of bias in the observational studies, and lack of comparisons/controls in the case series, the researchers noted. Notable literature gaps included data on outcomes including major bleeding and the need for surgery or additional treatments in the first review; mortality, major bleeding, spinal hematoma, transfusion, and thrombotic events in the second review; and mortality, major bleeding, and the need for other procedures in the third review.
However, the findings were strengthened by the use of broad eligibility criteria to include any studies with potential useful advice, including case series, if these were the only available options. In developing recommendations, “the guideline panel interpreted the evidence adding their experience and knowledge of indirect evidence,” the authors noted.
The current evidence, though mainly very low certainty, “is the best available to inform decisions about management. Clinicians seeking advice on how to manage their patients with VWD should refer to the practice guidelines and assess to what extent they are applicable to their patients,” the researchers concluded.