Heparin is a medication commonly known as a blood thinner, or anticoagulant, frequently prescribed to prevent and treat blood clots, such as deep vein thrombosis (DVT) or pulmonary embolism (PE). Many parents who require this medication often wonder about its safety during breastfeeding.
Breastfeeding While on Heparin
Healthcare providers generally consider it safe for parents to continue breastfeeding while taking heparin. This includes both unfractionated heparin (UFH) and low molecular weight heparins (LMWH), such as enoxaparin (Lovenox) and dalteparin. These medications are widely recommended because very little of the drug passes into breast milk. Even if trace amounts do transfer into the milk, they are poorly absorbed by an infant’s digestive system. Studies involving infants whose mothers were on LMWH have shown no adverse effects on the babies.
Why Heparin is Considered Safe
The safety of heparin during breastfeeding stems from its molecular characteristics. Both unfractionated heparin and low molecular weight heparins have large molecular sizes, making it difficult for them to cross from the bloodstream into breast milk in significant amounts. This substantial size limits their excretion into breast milk.
Furthermore, heparin and LMWHs are large protein molecules that are not well absorbed orally. If any minimal quantity were to enter the breast milk, it would likely be broken down in the infant’s digestive system. This means that even if a tiny amount is ingested, it is highly unlikely to have any systemic effect on the baby. Research, including a 1996 study on enoxaparin, found no change in anticoagulant activity or evidence of bleeding in exclusively breastfed infants whose mothers received the medication.
Important Considerations for Parents
Parents taking heparin should always consult with their healthcare provider, such as a doctor or lactation consultant, to discuss their specific situation and medication regimen. It is important to inform all healthcare professionals involved in your care that you are breastfeeding. While no special monitoring of the infant is typically required when the parent is on heparin, parents should observe their baby for any unusual symptoms. Reporting any unexpected changes or concerns to the pediatrician is always advised. The consensus among medical professionals is that the benefits of breastfeeding generally outweigh the minimal theoretical risks associated with heparin.