Abstract Number: PB0402
Meeting: ISTH 2021 Congress
Theme: Fibrinogen, Fibrinolysis and Proteolysis » Fibrinogen and Factor XIII
Background: We report a patient with congenital hypofibrinogenemia showing embryo implantation, continuation of pregnancy, and delivery following the continuous transfusion of dry human fibrinogen preparations.
Aims: [Case report] A 38-year old woman underwent embryo transfer (pre-pregnancy fibrinogen [Fbg] activity and antigen levels: 33 and 91 mg/dL, respectively). During the 2nd embryo transfer (failure), the Fbg level just after Fbg supplementation was 145 mg/dL and 66 mg/dL on day 5. During the third attempt (successful), we supplemented 4 g of Fbg 2 days before the embryo transfer (day 0) and at days 2, 7, and 12 for stabilizing the endometrium. The Fbg levels at implantation were maintained at 150 mg/dL. In the early phase of pregnancy, we supplemented 4 g of Fbg (thrice/2 weeks) regularly; Fbg levels were maintained at > 150mg/dL. From the 32nd week of pregnancy, the baby gained weight and the Fbg levels decreased. Then, we supplemented 3 g of Fbg (thrice/week); Fbg levels were maintained at 130-150 mg/dL. Because the Fbg levels decreased from the 34th week, we supplemented 13 g of Fbg/week. A child was born in the 35th week via cesarean operation.
Methods: [Gene analysis] Genetic anlysis of the DNA base sequences of the PCR products of the Aα, Bβ, and γ chains confirmed heterozygosity, with the nucleotides TGT (normal, wild-type) and CGT (morph), which encoded the 326thamino acid in the γ chain of exon 8. Further, cysteine (normal, wild-type) was replaced with arginine (morph); thus far, no studies have reported this finding.
Results: [Discussion] Although Fbg is not reported to be necessary during implantation in natural pregnancies, herein, implantation was successful in the presence of Fbg levels > 150 mg/dL during embryo transfer.
Conclusions: Fbg levels > 150 mg/dL may be necessary for implantation during embryo transfer in patients with congenital hypofibrinogenemia.
To cite this abstract in AMA style:
Seki Y, Ushiki T, Masuko M, Takizawa J, Sone H, Okumura N. A Patient with Congenital Hypofibrinogenemia who Showed Embryo Implantation, Continuation of Pregnancy, and Delivery Following Continuous Transfusion of Dry Human Fibrinogen Preparations [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/a-patient-with-congenital-hypofibrinogenemia-who-showed-embryo-implantation-continuation-of-pregnancy-and-delivery-following-continuous-transfusion-of-dry-human-fibrinogen-preparations/. Accessed December 7, 2021.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-patient-with-congenital-hypofibrinogenemia-who-showed-embryo-implantation-continuation-of-pregnancy-and-delivery-following-continuous-transfusion-of-dry-human-fibrinogen-preparations/