The Duchess of Cambridge has been forced to cancel another engagement - for The Art Room, in London - as she continues to suffer from hyperemesis gravidarum of pregnancy. As we know, no one can rush these things & HG often worsens with succeeding pregnancies. Wishing her well... DorrisWedding vintage and antique wears for a wedding

HG symptoms are caused by levels of HCG (human chorionic gonadotropin) in a pregnant woman's body. If Kate is currently at 9-10 weeks pregnant, she's likely at peak HCG levels. Chart from http://nucopiamom.com/hcg-levels-and-a-miracle/