Skip to Main Content
The first stop for professional medicines advice

Using heparins during breastfeeding

Published
Topics: Cardiovascular system disordersDalteparinEnoxaparin · HeparinSafety in BreastfeedingTinzaparin ·

Low molecular weight heparin and unfractionated heparin can be used during breastfeeding. Recommendations apply to full term, healthy infants only.

Contents

  1. General considerations
  2. Recommendations
  3. Clinical considerations
  4. Specific recommendations
    1. Dalteparin
    2. Enoxaparin
    3. Tinzaparin
    4. Unfractionated heparin
  6. Patient Information
  7. Contact us
  8. About our recommendations
  9. Bibliography

General considerations

It is important to complete an individual risk assessment (SPS page) for your patient and to apply the principles of prescribing in breastfeeding (SPS page) when looking at the available information and making treatment decisions.

Recommendations

Any heparin (low molecular weight (LMWH), or unfractionated) can be used during breastfeeding.

Negligible amounts are expected to pass into breast milk due to the large molecular weight and any drug present in the breast milk would not be expected to be absorbed by the breastfed infant.

Clinical considerations

The choice of heparin will depend on the clinical indication. Treatment choice should be based on the clinical scenario with safety in breastfeeding a secondary consideration.

Specific recommendations

Dalteparin can be used during breastfeeding. Infant monitoring is still required

Infant monitoring

As a precaution, infants should be monitored for rare bruising on the skin or any unusual bleeding.

Monitoring the infant will quickly pick up any potential issues, but further investigation is usually required before the cause can be attributed to the medicine.

Further information

Limited published evidence indicates that dalteparin passes into breastmilk in very small amounts. Any drug present in the breast milk would not be expected to be absorbed by the breastfed infant.

Infant side effects from exposure via breastmilk have not been reported and would not be anticipated.

Dalteparin can be used in full-term neonates from birth.

Enoxaparin can be used during breastfeeding. Infant monitoring is still required

Infant monitoring

As a precaution, infants should be monitored for rare bruising on the skin or any unusual bleeding.

Monitoring the infant will quickly pick up any potential issues, but further investigation is usually required before the cause can be attributed to the medicine.

Further information

Limited published evidence indicates that enoxaparin passes into breastmilk in negligible amounts. Any drug present in the breast milk would not be expected to be absorbed by the breastfed infant.

Infant side effects from exposure via breastmilk have not been reported and would not be anticipated.

Enoxaparin can be used in full-term neonates from birth.

Tinzaparin can be used during breastfeeding. Infant monitoring is still required

Infant monitoring

As a precaution, infants should be monitored for rare bruising on the skin or any unusual bleeding.

Monitoring the infant will quickly pick up any potential issues, but further investigation is usually required before the cause can be attributed to the medicine.

Further information

There is no published evidence of use during breastfeeding. However, tinzaparin is expected to pass into breast milk in negligible amounts. Any drug present in the breast milk would not be expected to be absorbed by the breastfed infant.

Infant side effects from exposure via breastmilk have not been reported and would not be anticipated.

Tinzaparin can be used in infants from one month of age.

Unfractionated heparin can be used during breastfeeding. Infant monitoring is still required.

Infant monitoring

As a precaution, infants should be monitored for rare bruising on the skin or any unusual bleeding.

Monitoring the infant will quickly pick up any potential issues, but further investigation is usually required before the cause can be attributed to the medicine.

Further information

There is no published evidence of use during breastfeeding. However, due to its very high molecular weight, unfractionated heparin is expected to pass into breast milk in negligible amounts. Any drug present in the breast milk would not be expected to be absorbed by the breastfed infant.

Infant side effects from exposure via breastmilk have not been reported and would not be anticipated.

Unfractionated heparin can be used in full-term neonates from birth.

Patient Information

The NHS website provides advice for patients on the use of specific medicines in breastfeeding.

Contact us

Get in touch with the UK Drugs In Lactation Advisory Service (UKDILAS) (SPS page), our specialist breastfeeding medicines advice service if you need support in the following situations:

  • you need further advice
  • the medicine in question is not included here
  • the infant is unwell or premature
  • multiple medicines are being taken

About our recommendations

Recommendations are based on published evidence where available. However, evidence is generally very poor and limited, and can require professional interpretation. Assessments are often based on reviewing case reports which can be conflicting and lack detail.

If there is no published clinical evidence, assessments are based on: pharmacodynamic and pharmacokinetic principles, extrapolation from similar drugs, risk assessment of normal clinical use, expert advice, and unpublished data. Simulated data are now increasingly being used due to the ethical difficulties around gathering good quality evidence in this area.

Bibliography

Full referencing is available on request.