Birth weight baby was 4054 g; Foetal exposure during pregnancy; This is an observational study case, initially received from other health professional on 07-Jul-2020, concerning a female neonate, whose mother was 29-year-old pregnant female subject of body weight: 170 Ibs, height: 64.8 inches and body mass index (BMI) 28.5, enrolled in, a prospective observational study on pregnancy outcomes in women immunized with Flucelvax, seasonal cell culture influenza trivalent (TIVc) or quadrivalent (QIVc) vaccine during pregnancy.  The neonate's mother medical history included BMI high.  The neonate's mother concomitant medications included vitamins (unspecified vitamins) as obstetrics (OB) supplementation and TDAP (diphtheria vaccine toxoid, pertussis vaccine acellular, tetanus vaccine toxoid) as vaccine.  The neonate's mother had one previous pregnancy with one full term live birth. The neonate's mother had no maternal or paternal history with major congenital malformations (MCMs) and had no history of offspring with MCM. The neonate's mother did not use tobacco, alcohol or illicit drugs during pregnancy.  The mother's last menstrual period (LMP) date was 12-Aug-2019, the estimated delivery date (EDD) and corrected estimated date of delivery (CEDD) were reported as 18-May-2020. The type of pregnancy was singleton. The neonate's father was 33-year-old.  On 06-Nov-2019, the neonate's mother underwent the first trimester screen, nuchal translucency and initial ultrasound, and no MCM was noted.  On 11-Dec-2019, at approximately 17 weeks of gestation (calculated per LMP), the neonate's mother was administered Flucelvax QIVc (Flu Vaccine Cell Subunit QIV NVD) [influenza vaccine, subunit influenza virus vaccine polyvalent; dose: 0.5 ml, batch number: 261228, , route of administration, anatomical location and expiration date: not reported] (explicitly coded as Foetal exposure during pregnancy') for an influenza immunisation.   On the same day, the neonate's mother underwent the second trimester screen and maternal serum alpha-fetoprotein (MSAFP)/serum marker and no MCM was noted.  On 30-Dec-2019, the neonate's mother underwent anatomy ultrasound and no MCM was noted.  On 04-Mar-2020, 2 months and 22 days after vaccination, the neonate's mother developed anaemia and started treatment with ferrous sulfate (one tablet, every day, orally).  On 05-May-2020, the neonate's mother underwent ultrasound growth and no MCM was noted.  On 11-May-2020, at gestational age of 39 weeks (as reported), the mother delivered live female neonate by vaginal method of delivery. The neonate's birth weight was 4054 g, head circumference and length were not reported. Appearance, pulse, grimace response, activity, respiration (APGAR) score at one minute was 8, at five minutes was 9 and at ten minutes was not reported. No MCMs noted at birth.  At the time of initial reporting, the outcome of event high birthweight baby' was not reported.  Per company, the event of high birthweight baby' was assessed as serious due to criterion of medical significance.  The reporter did not provide causality assessment.  This case is linked to the case 202003846, the corresponding mother case.  Company comment: The neonate's mother was administered the suspect product, Flucelvax QIVc at approximately 17 weeks of gestation (explicitly coded as Foetal exposure during pregnancy'). Reportedly, at 39 weeks of gestation, the subject vaginally delivered male neonate whose birth weight was 4054 grams (coded as large for dates baby). Medical history of body mass index high confound causality. For the event large for dates baby, causal role of the suspect product is assessed as not related unrelated due to biological implausibility. Per some sources, the range of normal is between 2.5 and 4.5 kilograms. Foetal exposure during pregnancy is assessed as not related per company conventions.; Sender's Comments: The neonate's mother was administered the suspect product, Flucelvax QIVc at approximately 17 weeks of gestation (explicitly coded as Foetal exposure during pregnancy'). Reportedly, at 39 weeks of gestation, the subject vaginally delivered male neonate whose birth weight was 4054 grams (coded as large for dates baby). Medical history of body mass index high confound causality. For the event large for dates baby, causal role of the suspect product is assessed as not related unrelated due to biological implausibility. Per some sources, the range of normal is between 2.5 and 4.5 kilograms. Foetal exposure during pregnancy is assessed as not related per company conventions.