Two scientific studies, one in Norwegian (Tidsskr Nor Laegeforen) and one in English (Eur J Clin Pharmacol) were published in February and can be found here:
Nordeng S, Nordeng H, Høye S. [Use of antibiotics during pregnancy]. Tidsskr Nor Laegeforen. 2016 Feb 23;136(4):317-21. In Norwegian. Link
Heitmann K, Havnen GC, Holst L, Nordeng H. Pregnancy outcomes after prenatal exposure to echinacea: the Norwegian Mother and Child Cohort Study. Eur J Clin Pharmacol. 2016 Feb 19. Link