Birth weight of baby was 4054 g at gestational age 39.6 weeks/Large for gestational age; Unspecified pregnancy complication; Vaccine exposure during pregnancy; This is a serious observational study case, initially received from other health professional on 16-Jul-2019, concerning a 31-year-old, adult female pregnant subject of body weight: 120 lbs, height: 63 inches and body mass index (BMI): 21.3 enrolled in a 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 one previous pregnancy which included one spontaneous abortion. The subject did not have any history of previous birth defect. On an unknown date, the subject's family history of major congenital malformation was collected, and the subject had no maternal/paternal history with major congenital malformations. The subject's historical condition included bacterial vaginosis and candida vaginitis (both from 11-May-2018 to 22-May-2018). The subject's historical drug included Metrogel (metronidazole, 0.75 percent twice daily vaginally from 15-May-2018 to 22-May-2018) for vaginitis. The subject's concomitant medications included Prenatal vitamins (vitamin NOS, mineral NOS) for pregnancy.  The subject's last menstrual period (LMP) date was 10-Feb-2018. The type of pregnancy was singleton. The subject did not consume tobacco, alcohol and illicit-drugs during pregnancy.  On 30-Apr-2018, the subject underwent haemoglobin (Hgb) electrophoresis, spinal muscular atrophy, cystic fibrosis mutation analysis and no congenital malformation was reported. On 11-May-2018, the subject underwent ultrasound scan and no congenital malformation was reported. On 06-Jun-2018, the subject underwent ultrasound scan and Quad screen analysis and no congenital malformation was reported. On 24-Sep-2018, the subject underwent ultrasound scan and no congenital malformation was reported.  On 08-Oct-2018, approximately at gestational age of 34 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 an unknown date, unspecified time after vaccination, the subject was noted to have unspecified pregnancy complication.  On 14-Nov-2018, at gestational age of 39.6 weeks, the subject delivered male neonate through caesarean method of delivery and no pregnancy complications were observed. The birth weight of the neonate was 4054 g (explicitly coded as large for gestational age), head circumference was 35.6 cm and length was 50.8 cm. Appearance, pulse, grimace, activity and respiration (APGAR) score at one minute was 9, at five minutes was 9 and no data was reported for APGAR score at ten minutes. No major congenital malformation was identified at birth.  The outcome of the event 'unspecified pregnancy complication' was not reported.  The subject's estimated delivery date (EDD) and corrected estimated delivery date (CEDD) was 17-Nov-2018.  This case is cross linked to the case: 201904145 (baby case).; Reporter's Comments: A 31-year-old female pregnant subject experienced unspecified pregnancy complication, unspecified period after receipt of Flu vaccine cell subunit QIV at approximately 34 weeks of gestation (considered as vaccine exposure during pregnancy). Considering the lack of information regarding the reported pregnancy complication and onset latency, the causal role of study vaccine assessed as unassessable. The subject delivered large for gestational age (LGA) baby (4054 grams) at 39.6 weeks of gestation by caesarean section. The known aetiologies of LGA includes genetic, increased maternal weight gain during pregnancy and maternal gestational diabetes. Considering the lack of biological evidence associated with study vaccine, the causality of event LGA assessed as not related. Also, the temporal relationship between vaccination and reported event LGA appear to be unlikely. 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).