This is a serious observational study case, initially received from other health professional on 18-Feb-2019, concerning a 21-year-old, adult female pregnant subject of body weight: 140 lbs, height: 63 inches and body mass index (BMI): 24.8, prospective observational safety study on pregnancy outcomes in women immunized with seasonal cell culture influenza trivalent (TIVc) or quadrivalent (QIVc) vaccine during pregnancy. The subject had no maternal and paternal history of major congenital malformations. The subject had no history of offspring with major congenital malformations. The subject had 2 previous pregnancy reported in which both were of spontaneous abortions. The subject did not use tobacco, alcohol or illicit drugs during pregnancy. The subject's historical condition included bacterial vaginitis. The subject's historical drugs included metrogel for bacterial vaginitis. The subject's current conditions included anaemia and hyperemesis. The subject's concomitant medications included Prenatal Vitamins (minerals nos, vitamins nos) for pregnancy, promethazine for hyperemesis and ferrous sulfate for anaemia. The subject's last menstrual period (LMP) date was 20-Mar-2018. The type of pregnancy was singleton. On 01-May-2018, the subject had undergone haemoglobin electrophoresis test, spinal muscular atrophy and cystic fibrosis mutation and no major congenital malformation was noted. On 10-May-2018, the subject experienced vaginitis and had undergone ultrasound screening and subchorionic haemorrhage and echogenic cardiac focus were identified. On 17-May-2018, the vaginitis was recovered. On 23-May-2018, 07-Jun-2018 and 11-Jun-2018, the subject had undergone ultrasound screening and ultrasound screening and subchorionic haemorrhage and echogenic cardiac focus were again identified. On 22-Jun-2018, the subject experienced vaginitis again which was recovered on 23-Jun-2018. On 11-Jul-2018, the subject had undergone maternal serum alpha-fetoprotein (MSAFP)/serum markers test and Q-Natal test no major congenital malformation was noted. On 28-Sep-2018, the subject developed candidiasis and was treated with Terazol (terconazole) and Flagyl (metronidazole). On 29-Sep-2018, the subject recovered from candidiasis. On 03-Oct-2018, at gestational age of 28 weeks, the subject was administered Flu Vaccine Cell Subunit QIV NVD (influenza vaccine, subunit influenza virus vaccine polyvalent, batch number: 252664, dose, route of administration, anatomical location and expiry date: not reported) (explicitly coded as vaccine exposure during pregnancy) for an unknown indication. On 31-Oct-2018, the subject had undergone ultrasound screening and no major congenital malformation was noted. On the same day, the subchorionic haemorrhage was resolved. On 26-Nov-2018, 1 month and 23 days after vaccination, the subject experienced cellulitis. The subject was treated with Keflex (cefalexin) for cellulitis for 7 days.  The outcome of the event cellulitis was recovered on 03-Dec-2018. The subject (at the gestational age of 39.1 weeks) gave live birth to male infant of body weight: 2745 grams, head circumference: 32.4 cm and body length: 47 cm. The Apgar score of the infant at one minute was 8 and 5 minutes was 9 and no major congenital malformation was identified at birth. The delivery method was vaginal, and no pregnancy complications were noted at birth. The subject's estimated delivery date (EDD) was reported as 31-Dec-2018. There were no changes to maternal paternal information since last visit.; Reporter's Comments: A 21-year-old pregnant subject experienced cellulitis, 1 month 23 days after receipt of Flu Vaccine Cell Subunit QIV NVD (vaccine exposure during pregnancy). Considering implausible temporal relationship between vaccination and reported event cellulitis, the causality assessed as not related to study vaccine. The decision to administer a vaccine during pregnancy is related to medical decision made by the mother and her physician and is not related to any property of the medication. Hence, the event vaccine exposure during pregnancy assessed as not related considering the intended use of the vaccine. The company assessed the case as serious (medically significant).