[1] Rigshosp, Univ Dept Growth & Reprod, DK-2100 Copenhagen, Denmark
[2] Rigshosp, Univ Dept Neonatol, DK-2100 Copenhagen, Denmark
[3] Sygehus Vestsjaelland, Dept Gynecol & Obstet, Holbaek, Denmark
[4] Rigshosp, Univ Dept Biochem, DK-2100 Copenhagen, Denmark
[5] Statens Serum Inst, Dept Clin Biochem, DK-2300 Copenhagen, Denmark
[6] Glostrup Cty Hosp, Dept Clin Physiol & Nucl Med, Glostrup, Denmark