This handout is for vte in pregnancy and postpartum. Your care team identified this based on: unilateral leg swelling + pain + erythema in pregnant or postpartum patient — dvt until proven otherwise; compression us first-line (acog pb 196 pmid 29939938).
Other reasons your team may use this plan: pleuritic chest pain ± dyspnea ± hemoptysis in pregnant or postpartum patient — pe until proven otherwise; pregnancy-adapted years algorithm (van der pol 2019 pmid 30893534); unexplained sinus tachycardia (hr > 100) or hypoxemia (spo2 < 95% on room air) in pregnant or postpartum patient — pe workup mandatory; sudden cardiopulmonary collapse + hypotension + rv failure in pregnant or postpartum patient — massive pe; consider thrombolysis or surgical thrombectomy; afe differential (ob.amniotic-fluid-embolism.v1).
Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.
| Medication | Starting dose | How | When | What it does |
|---|---|---|---|---|
| enoxaparin | Therapeutic: 1 mg/kg SC q12h (weight-based). Prophylactic: 40 mg SC daily (or 30 mg SC q12h if BMI > 40) | SC | q12h therapeutic; daily prophylactic | PregCat: former B — extensive pregnancy experience; LMWH does not cross placenta (large molecular weight ~ 4-6 kDa). | Lactation: compatible per LactMed — large molecular weight prevents milk transfer; routinely used postpartum. | First-line acute VTE treatment per ASH 2018 STRONG recommendation (Bates PMID 30482767) over UFH because of more predictable PK, lower HIT risk, and outpatient feasibility; weight-based dosing q12h preferred (twice-daily preferred to once-daily in pregnancy per conditional ASH recommendation due to expanded plasma volume + glomerular hyperfiltration); anti-Xa monitoring NOT routine. |
| heparin | Therapeutic: 80 units/kg IV bolus + 18 units/kg/h infusion; titrate aPTT 1.5-2.5x control. Prophylactic SC: 5000 units SC q8-12h | IV/SC | continuous (therapeutic IV) or q8-12h (prophylactic SC) | PregCat: former C — long pregnancy experience; UFH does not cross placenta. | Lactation: compatible per LactMed — does not transfer in significant amounts; routine postpartum use. | Reserved per ASH 2018 (Bates PMID 30482767) for renal impairment (eGFR < 30 favors UFH given LMWH renal clearance) or near-delivery period when shorter half-life + IV reversibility (protamine) is advantageous; transition from LMWH to UFH 24 h before scheduled induction/elective cesarean for therapeutic dose, 12 h before for prophylactic — enables neuraxial anesthesia per ASRA + ACOG PB 196 guidance. |
| warfarin | 5 mg PO daily POSTPARTUM ONLY; titrate to INR 2-3 (target depends on indication and bridging plan) | PO | daily | PregCat: former X in pregnancy — warfarin embryopathy (nasal hypoplasia, stippled epiphyses) at 6-12 wk; fetal CNS abnormalities + fetal hemorrhage later in pregnancy; STRICTLY CONTRAINDICATED throughout pregnancy. | Lactation: compatible POSTPARTUM per LactMed — does not transfer to breast milk in significant amounts; safe during breastfeeding. | Standard postpartum anticoagulation option when continued therapy needed beyond 6 wk postpartum; bridge with LMWH/UFH until INR therapeutic for 24-48 h then stop heparin; AVOID re-initiation if next pregnancy planned (switch back to LMWH preconception or at first positive pregnancy test). |
| alteplase | 100 mg IV over 2 h (standard PE regimen); 50 mg IV bolus if cardiac arrest | IV | single infusion | PregCat: former C — large molecule unlikely to cross placenta in significant amounts but limited pregnancy data. | Lactation: limited-data per LactMed — short half-life (~ 5 min); resume breastfeeding 24-48 h post-infusion reasonable. | Reserved for LIFE-THREATENING massive PE (SBP < 90 sustained, RV failure, cardiac arrest) where survival benefit outweighs hemorrhage risk; ASH 2018 (Bates PMID 30482767) discusses thrombolysis as reasonable for life-threatening PE in pregnancy; coordinate with critical care + hematology + obstetrics + neurology for intracranial hemorrhage risk discussion; catheter-directed thrombolysis is selective alternative. |
| IVC filter retrievable | — | — | — | PregCat: N/A — device. | Lactation: N/A — device. | ONLY for absolute anticoagulation contraindication (active major hemorrhage, recent intracranial bleed, severe thrombocytopenia); retrievable filter preferred + remove as soon as anticoagulation feasible; framework per ACOG PB 196 (PMID 29939938) + ASH 2018 (PMID 30482767). |
| apixaban | — | — | — | PregCat: former B label but CONTRAINDICATED in pregnancy per ASH 2018 (Bates PMID 30482767) — limited pregnancy data, no formal recommendation. | Lactation: CONTRAINDICATED per ASH 2018 — small molecule likely crosses into breast milk; insufficient data on infant exposure. | Documented to flag the safety rule; transition to LMWH if patient becomes pregnant while on apixaban — switch as soon as pregnancy recognised; do NOT use postpartum in breastfeeding patients. |
| rivaroxaban | — | — | — | PregCat: former C — CONTRAINDICATED in pregnancy per ASH 2018 (Bates PMID 30482767) — placental transfer demonstrated in animal studies + insufficient human data. | Lactation: CONTRAINDICATED per ASH 2018 — small molecule crosses into milk in animal studies + insufficient human data. | Documented to flag the safety rule; transition to LMWH if patient becomes pregnant while on rivaroxaban — switch as soon as pregnancy recognised; do NOT use postpartum in breastfeeding patients. |
Plan: VTE in pregnancy and postpartum — LMWH backbone + UFH transition near delivery + warfarin postpartum only + alteplase for massive PE + IVC filter for absolute anticoagulation contraindication + DOACs explicitly CONTRAINDICATED (ACOG PB 196 PMID 29939938 + ASH 2018 Bates PMID 30482767 + van der Pol YEARS NEJM 2019 PMID 30893534)
Contact your care team if any of the following happen:
Call 911 or go to the nearest emergency room right away if you have:
Continue anticoagulation 3 mo total OR 6 wk postpartum (whichever is longer) per ACOG PB 196 (PMID 29939938) + ASH 2018 (Bates PMID 30482767). Postpartum transition: warfarin acceptable (LactMed compatible — no milk transfer) OR continue LMWH/fondaparinux throughout breastfeeding; AVOID DOACs during breastfeeding per ASH 2018. Thrombophilia workup AFTER anticoagulation completed (acute thrombus + heparin confound results). Subsequent-pregnancy counseling: prophylactic LMWH throughout pregnancy + 6 wk postpartum if VTE in prior pregnancy or known thrombophilia (ACOG PB 196 risk-stratified). Contraception counseling: AVOID combined OCs (estrogen) given VTE history; progestin-only methods or non-hormonal preferred. Lifestyle: weight optimization, smoking cessation, mobility.
Guideline: ACOG Practice Bulletin 196 (2018) Thromboembolism in Pregnancy + American Society of Hematology 2018 guidelines for VTE in pregnancy (Bates et al, Blood Adv) + Pregnancy-Adapted YEARS NEJM 2019 (van der Pol) for diagnostic algorithm