GlaxoSmithKline Plc, the U.K.’s largest drugmaker, failed to properly warn consumers that its antidepressant drug Paxil could cause birth defects, a lawyer for the family of an injured teenager told jurors. Glaxo officials had research from the 1980s showing Paxil caused deaths among the offspring of animal test subjects and didn’t provide clear warnings about those deaths, Kimberly Baden, a lawyer for Anna Blyth and her family, told a Philadelphia jury. Baden said the drug caused a narrowing of the aorta leading from the heart of Anna, now 14 years old.