I appreciate your query.
definitely interferes with the urinary pregnancy
The article you mentioned in Lancet is from 1984, but I can suggest you other references also that mention the same phenomenon.
The references are :
1. Human chorionic gonadotropin
in pregnancy diagnostics
Clinica Chimica Acta, doi:10.1016/j.cca.2011.05.025
2. Kaplan and Sadock ́s pocket handbook of psychiatric drug treatment. This book also contains details of the same.
Hence, you cannot rely on home pregnancy tests , if using carbamazepine.
Please consult your gynecologist and rely on blood B - HCG estimation or better still, an ultrasound
for confirmation of diagnosis.
Hope this helped you.