There are many anticoagulant agents including newer agents with limited use and evidence in lactating parents (1).
For more detailed information and references on specific medications, please refer to LactMed, e-lactancia, Infant Risk, or Mother to Baby.
Aspirin is generally considered safe in lactation. The other medications in this class are relatively new with limited data or have high levels in breastmilk so thorough risk benefit discussions should be had and alternatives are preferred if available.
- Aspirin: There is no absolute indication to pump and dump.
- P2Y12 ADP receptor blockers (clopidigrel/Plavix, ticagrelor/Brillinta, ticlopidine, prasugrel/Effient): Infants of lactating parents who are on these medications should be monitored for bruising. As Ticagrelor and its metabolite are 99% bound to plasma proteins, there is minimal transfer to milk, and it is likely safe. While alternative medications should be considered due to a lack of data and infants should be monitored for bruising with the use of these medications, there is no absolute indication to pump and dump and shared decision making is recommended with this class of medications.
- Glycoprotein 2b/3a receptor blockers (abciximab, eptifibatide, tirofiban): Due to the lack of data is available on these medications, avoidance of their use during lactation is recommended. However, the drug molecules are large polypeptides so their excretion into milk theoretically should be very low. Lactating parents may choose to feed through and monitor their infants for bruising if they must be on one of these medications. While alternative medications should be considered due to a lack of data and infants should be monitored for bruising with the use of these medications, there is no absolute indication to pump and dump and shared decision making is recommended with this class of medications.
- Phosphodiesterase inhibitors (dipyridamole, cilostazol): While little information on these drugs is available, they are found to be available in high levels in human milk. Alternative medications should be considered due to the high milk levels of these medications.
Heparin & Low Molecular Weight Heparins
Very small amounts of these large molecular weight medications get into the breastmilk and they have low oral bioavailability for the infant (2). There is no absolute indication to pump and dump with heparin or low molecular weight heparins (dalteparin, enoxaparin/Lovenox).
Synthetic Selective Factor Xa Inhibitor
There is no data on the use of fondaparinux/Arixtra in lactation. This medication has a high molecular weight, is highly protein bound, and has low oral bioavailability, making it highly unlikely that the infant would be exposed to significant amounts of medication via breastmilk. Premature and newborn infants may have a higher risk of absorbing this medication via the gut so caution should be used in lactating individuals with young or premature babies. While there is a lack of data on the use of this medication by lactating individuals and infants should be monitored for signs of bleeding, there is no absolute indication to pump and dump with fondaparinux and shared decision making should be utilized regarding the use of this medication in lactating individuals.
Factor Xa Inhibitors
- Rivaroxiban: Small amounts are excreted into breastmilk. Preterm and newborn infants should be monitored for signs of bleeding. While infants should be monitored for signs of bleeding, there is no absolute indication to pump and dump.
- Apixiban/Eliquis: Early data on apixaban (Eliquis) indicates that it is excreted into breastmilk and the safety of this medication in lactation is unknown (3). Alternative medications should be considered due to the known excretion of this medication into breastmilk and a lack of safety data.
Direct Thrombin Inhibitors/Direct Acting Oral Anticoagulants (DOACs)
- Univalent (argatroban, dabigatran) No studies are available on argatroban, but small studies on dabigatran show that minimal amounts are excreted in breastmilk, though infant’s serum levels seem insufficient to have any effect on clotting (4). Alternative medications should be considered due to the known excretion of these medications into breastmilk and a lack of safety data.
- Bivalent (bivalirudin): Alternative medications should be considered due to the lack of data with this medication (4).
Warfarin/Vit K Inhibitors
Warfarin is generally considered safe in lactating parents because of very low transmission into breastmilk. There is no absolute indication to pump and dump.
Alteplase is a normal component of human milk with the highest levels of this compound found in colostrum. No studies are available on milk levels after exogenous administration, but this medication is likely safe to use in the lactating parent because it is a large protein molecule with probable destruction of this medication in the infant’s gastrointestinal tract. While this medication should be used with caution in lactating parents of newborns and preterm infants due to limited data, there is no absolute indication to pump and dump.
- Bates SM, Rajasekhar A, Middeldorp S, et al. American Society of Hematology 2018 guidelines for management of venous thromboembolism: Venous thromboembolism in the context of pregnancy. Blood Adv 2018;2:3317-59. doi: 10.1182/bloodadvances.2018024802 (Accessed August 2022).
- Richter C, Sitzmann J, Lang P, et al. Excretion of low molecular weight heparin in human milk. Br J Clin Pharmacol. 2001;52:708–10. doi: 10.1046/j.0306-5251.2001.01517.x (Accessed August 2022).
- Datta P, Bramnik A, Rewers-Felkins K, et al. Transfer of apixaban into human milk. Obstet Gynecol 2021;137:1080-2. doi: 10.1097/AOG.0000000000004388 (Accessed August 2022).
- Daei M, Khalili H, Heidari Z. Direct oral anticoagulant safety during breastfeeding: A narrative review. Eur J Clin Pharmacol 2021. doi: 10.1007/s00228-021-03154-5 (Accessed August 2022).