This prospective pregnancy case was reported in a literature article and described the occurrence of vaccination failure in a adult female subject who received Flu seasonal TIV Dresden. On an unknown date, unknown after receiving Flu seasonal TIV Dresden, the subject developed vaccination failure. Serious criteria included hospitalization and GSK medically significant. Additional event(s) included influenza with serious criteria of hospitalization and vaccine exposure during pregnancy. The outcome of vaccination failure was unknown. The outcome(s) of the additional event(s) included influenza (unknown) and vaccine exposure during pregnancy (unknown). The pregnancy was lost to follow up. The investigator considered that there was a reasonable possibility that the vaccination failure, influenza and vaccine exposure during pregnancy may have been caused by Flu seasonal TIV Dresden. Relevant Tests: Lab tests were performed on an unspecified date. The patient was diagnosed with laboratory confirmed influenza infection. Diagnostic results (unless otherwise stated, normal values were not provided): On an unknown date, Influenza virus test result was see text unknown. Additional information was provided. This prospective pregnancy case was reported in a literature article and described suspected vaccination failure in a pregnant female aged between 40 and 49-year who was vaccinated with unspecified seasonal influenza vaccine (manufacturer unknown) during pregnancy. The patient was part of the study that analysed 2010 census and 2008- 2012 community survey data from 14 sites and conducted population-based surveillance or laboratory-confirmed influenza-associated hospitalizations among residents of 78 counties. The patient's last menstrual period was on an unknown date. Estimated date of delivery was on an unknown date. No information on patient's medical or family history or concomitant medication or was provided. On an unspecified date during 2010-2011 or 2011-2012 influenza season, the patient received unspecified seasonal influenza vaccine (administration site and route unspecified; dosages unknown; batch number not provided) during pregnancy. The age of vaccination was not provided. On an unspecified date during 2010-2011 or 2011- 2012 influenza season, an unknown period after the vaccination, the patient developed influenza infection. Subsequently, the patient was diagnosed with laboratory confirmed influenza infection. The patient was hospitalised. (In this study, laboratory-confirmed influenza-associated hospitalisations were defined as hospitalization of persons residing in the surveillance area less than or equal to 14 days after or equal to less than 3 days before a positive influenza test result during 1 October and 1 April each year). This case has been considered as suspected vaccination failure being time to onset was unknown. This case has been considered serious due to hospitalisation/suspected vaccination failure. Treatment was unknown. The outcome of the event was not reported. The pregnancy outcome was lost to follow up. The authors did not comment on the event of influenza infection and unspecified seasonal influenza vaccine. The authors concluded "Overall rates of influenza-associated hospitalization were not significantly different for men and women after excluding pregnant women. Among women aged 18-49, pregnancy increased the risk of influenza-associated hospitalization six-fold but did not increase the likelihood of vaccination. Improving vaccination rates in pregnant women should be an influenza vaccination priority".