Is treatment with Fragmin (dalteparin) compatible with breast-feeding?/nBackground: A woman will un

Fråga: Is treatment with Fragmin (dalteparin) compatible with breast-feeding?

Background: A woman will undergo orthopedic surgery two days after delivery, and will receive routine thromboprophylaxis with an anticoagulant.

Sammanfattning: The available data in the literature is limited but indicate that it is highly unlikely that administration of low-molecular weight heparin to the mother has any clinically relevant effects on the nursing infant.

Svar: A previous answer by DRIC to this question concluded that the issue of low-molecular weight heparins and lactation was poorly investigated, but that it was unlikely that dalteparin would be transferred to breast milk to any significant extent, and that the oral absorption by the baby would be expected to be low (1). A similar reasoning has been made elsewhere (2), where the conclusion is that significant biological effects on the baby seem unlikely.

Only a single relevant report on the subject was retrieved in an updated literature search (3). This report includes data from 15 mothers treated with daily subcutaneous doses of dalteparin (2500 IU) the first week after uncomplicated pregnancy and delivery by Caesarean section. Anti-factor Xa activity was measured in plasma and milk 3-4 h after an injection of dalteparin. There was a marked variability in milk/plasma ratio of anti-Xa activity, ranging from undetectable levels in four cases to 0.22 in a single case. The authors conclude that the maximal daily oral exposure to a child drinking 250 ml of milk would correspond to 5% of the mother´s dose adjusted for bodyweight. Based on observations in previous publications saying that 5000 IU of low-molecular weight heparin given orally to patients, did not result in any measurable plasma activity, the authors concluded that it is highly unlikely that thromboprophylaxis with low-molecular weight heparin has any clinically relevant effects on the nursing infant. 1 Drugline no 12324 (year 1995) 2 Läkemedel och amning. Uppdated 2001. Available from: URL: http://www.janusinfo.org 3 Richter C, Sitzmann J, Lang P, Weitzel H, Huch A, Huch R. Excretion of low molecular weight heparin in human milk. Br J Clin Pharmacol 2001;52:708-10.