Safety and efficacy of low-molecular-weight heparin related to pregnancy and risk of thromboembolism in the postpartum-period
Year: 2017
Type: dissertation
Study design: Observational Study
Abstract: Venous thromboembolic event (VTE) is one of the leading causes of maternal deaths in the Western world, with highest risk during the postpartum period. Low-molecular-weight heparin (LMWH) is currently the medicine of choice for the management of acute VTE and for VTE prophylaxis during pregnancy. The aims of the study were to evaluate the maternal and neonatal safety and the efficacy of the long-term use of LMWH during pregnancy, and the incidence, risk factors, and mortality of postpartum VTE in Finland through 180 days after delivery. The safety and efficacy of LMWH exposure during pregnancy were evaluated in studies I-III. LMWH exposed women (n=475), were included in Study I (1994-2007). Study II was a sub-study of Study I concerning recurrent VTEs in women with a history of previous VTE (n=271). Whether there is a subsequent decrease in bone mineral density (BMD) after long-term use of LMWH during pregnancy, was observed in study III (2008-2012), by measuring BMD in women with (n=92) and without LMWH exposure (n=60). Study IV (2001-2011) was a population-based study to assess the incidence and risk factors for postpartum VTE 180 days after delivery. The study population consists of all women with deliveries (N=634292) and all fertile-aged non-pregnant women (N=1232841). Women with VTE after delivery were collected. The incidences of thrombocytopenia, bleeding, preterm delivery, stillbirth, pre-eclampsia, or fetal growth restriction were same between LMWH-exposed women and healthy controls and no heparin-induced thrombocytopenia or osteoporotic fractures were observed. Few allergic reactions for LMWH occurred. The incidence of VTE despite ongoing LMWH prophylaxis was high in women with a history of at least two VTEs, prior estrogen - or antiphospholipid antibody syndrome -related VTE. LMWH was not associated with decreased BMD. The risk of postpartum VTE was highest during the first week declining thereafter, but small residual risk remained through 175 postpartum days. The VTE risk remained elevated for 180 days in women with thrombophilia, Cesarean section, twin birth, varicose veins, and cardiac disease. Three VTE-related deaths occurred. We showed that the use of LMWH during pregnancy was safe for both the mother and the fetus. The recurrence rate of VTE was high in high-risk women. Small residual VTE risk remained elevated for six months after delivery. Studies on the optimal dosing and duration of LMWH in high-risk groups are needed.
Source: Työväentutkimus Vuosikirja
Author: Päivi J. Galambosi
Language: English
Subfield: Internal Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2605675963