Foetal exposure during pregnancy; Low birth weight; This is an observational study case, initially received from other health professional on 02-Dec-2019 concerning a female neonatal subject whose mother was 45-year-old pregnant, female subject of body weight: 222 Ibs, height: 65 in and body mass index (BMI) 36.9 enrolled in a prospective observational safety study. The subject's father was 47-year-old.  The subject's mother had five previous pregnancies with two spontaneous abortions and three full term live birth pregnancies with no birth defects. The subject's mother had no maternal or paternal history with major congenital malformations (MCMs). The subject's mother had no history of offspring with MCM. The subject's mother used half pack of cigarettes per day during pregnancy. The subject's mother did not use alcohol or illicit drugs during pregnancy.  The mother's current medical condition included deep vein thrombosis. The mother's concomitant medications included enoxaparin and Aspirin (acetylsalicylic acid), both for deep vein thrombosis, and prenatal vitamins (unspecified vitamins and minerals) for pregnancy.   The mother's last menstrual period (LMP) date was on 15-Mar-2019. Estimated delivery date (EDD) was reported as 15-Dec-2019 and corrected estimated date of delivery (CEDD) was reported as 18-Dec-2019. The type of pregnancy was singleton.   On 31-May-2019, the subject's mother underwent ultrasound and no MCMs were noted. On the same day, the subject's mother underwent Maternit 21 and increased risk for chromosome 21 was noted.  On 24-Oct-2019, at approximately 31 weeks of gestation, the subject's mother was administered Flu Vaccine Cell Subunit QIV NVD (Flucelvax QIVc) [influenza vaccine, subunit influenza virus vaccine polyvalent; batch number: 261226, dose: 0.5 mL, route of administration, anatomical location and expiration date: not reported] (explicitly coded as Foetal exposure during pregnancy') for influenza immunisation.   At approximately 37 weeks of gestation, the mother delivered a live female neonate via Caesarean method. The neonate's birth weight was 2211 grams, body length and head circumference were not reported. The reported appearance, pulse, grimace, activity, and respiration (APGAR) score at one minute was 7, at five minutes was 9 and no data was provided at 10 minutes. No MCMs were identified at birth.  At the time of initial reporting, the outcome for the event of low birth weight baby was not reported.  Per company, the event of low birth weight baby was assessed as serious due to criterion of medical significance.   The reporter did not provide causality assessment to Flucelvax QIVc.  This case is linked to case number 201907068 (corresponding mother case).  Company Comment: The female neonatal subject was delivered as low birth weight baby after foetal exposure during pregnancy (at approximately 31 weeks of gestation) with the suspect product Flucelvax QIV. Chronology is plausible. Mother's medical history of cigarette smoking may provide more plausible alternative aetiology for the event. Mother's concomitant medications, enoxaparin and Aspirin (acetylsalicylic acid), and obesity body mass index (36.9) may have also contributed to development of the event in significant way. Foetal exposure during pregnancy is assessed as not related per company's conventions. For the event low birth weight baby, causal role of the suspect product cannot be totally excluded and is assessed as unlikely related.; Sender's Comments: The female neonatal subject was delivered as low birth weight baby after foetal exposure during pregnancy (at approximately 31 weeks of gestation) with the suspect product Flucelvax QIV. Chronology is plausible. Mother's medical history of cigarette smoking may provide more plausible alternative aetiology for the event. Mother's concomitant medications, enoxaparin and Aspirin (acetylsalicylic acid), and obesity body mass index (36.9) may have also contributed to development of the event in significant way. Foetal exposure during pregnancy is assessed as not related per company's conventions. For the event low birth weight baby, causal role of the suspect product cannot be totally excluded and is assessed as unlikely related.