title: Vitamin K1 levels and coagulation factors in healthy term newborns till 4 weeks after birth.
abstract: Vitamin K1 serum levels were assessed by means of an off-line multidimensional liquid chromatography in 18 mothers, shortly after delivery, and in their healthy term infants. Umbilical cord and venous blood samples were assayed up to 4 weeks of life. Concurrently, levels of coagulation factors II and X, antithrombin III and platelets were established. Although the detection limit of the assay was as low as 22 pg/ml, vitamin K1 concentration appeared to be still beyond that level in cord blood or in newborn serum within 30 min after birth, whereas vitamin-K-dependent coagulation factors are already at a level of 40%, without evidence for the presence of descarboxy prothrombin, in any of the investigated neonates. After 3 days, breast-fed neonates had lower vitamin K1 levels than formula-fed infants (0.76 and 1.44 ng/ml, respectively). The levels of the vitamin-K-dependent coagulation factors II and X, however, were comparable, regardless of the kind of feeding. After 28 days, breast-fed neonates had even lower vitamin K1 levels (0.49 ng/ml, while the formula-fed infants showed higher vitamin K1 levels (4.45 ng/ml). But even then, the levels of vitamin-K-dependent coagulation factors II and X were comparable, regardless of the kind of feeding. From this we conclude that the serum levels of vitamin K1 in formula-fed neonates exceed those of breast-fed infants from the moment of feeding (24 h and later) without a concomitant rise in vitamin-K-dependent coagulation factors. A relationship between vitamin K1 levels and vitamin-K-dependent coagulation factors could not be established in healthy term breast-fed or formula-fed infants.
authors.affiliation: Department of Gynecology and Obstetrics, Reinier de Graaf Gasthuis, The Netherlands.
authors.forename: A L
authors.initials: AL
authors.lastname: Pietersma-de Bruyn
authors.forename: P M
authors.initials: PM
authors.lastname: van Haard
authors.forename: M H
authors.initials: MH
authors.lastname: Beunis
authors.forename: K
authors.initials: K
authors.lastname: Hamulyák
authors.forename: J C
authors.initials: JC
authors.lastname: Kuijpers
mesh_terms: D001942:Breast Feeding; D005170:Factor X / Q000032:analysis*; D005312:Fetal Blood / Q000032:analysis; D006801:Humans; D007225:Infant Food; D007231:Infant, Newborn / Q000097:blood*; D011516:Prothrombin / Q000032:analysis*; D010837:Vitamin K 1 / Q000097:blood*
chemical_list: D010837:Vitamin K 1; D011516:Prothrombin; D005170:Factor X