The length of time a pregnant woman needs to be given heparin if she is prone to embolism cannot be generalised, but is determined by her condition and relevant indicators. If a pregnant woman has a history of unexplained miscarriage, persistent elevated D-dimer levels, advanced age, excessive obesity, antiphospholipid syndrome or other common risk factors for embolism, then heparin/low-molecular-weight heparin may be chosen for prophylactic intervention depending on the risk level.
During treatment, regular review of relevant indicators and assessment of bleeding risk is required. Some pregnant women may require heparin/low-molecular-weight heparin throughout pregnancy until about 6 weeks after delivery, when the decision to continue anticoagulation is made on a case-by-case basis after assessing the risk of thrombosis, but long-term anticoagulation carries a risk of bleeding and therefore the medication should be administered strictly in accordance with medical advice.