Foetal exposure during pregnancy; Low birth weight; This is an observational study case, initially received from other health professional on 27-Nov-2019, concerning a female neonatal subject whose mother was 21-year-old pregnant, female subject of body weight: 155 Ibs, height: 67 in and body mass index (BMI) 24.3 enrolled in a prospective observational safety study.   The subject's mother had four previous pregnancies with two spontaneous abortion and two full term live births 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 cigarette during pregnancy, one pack per day. The subject's mother did not use alcohol or illicit drugs during pregnancy.  The mother's historical condition included bacterial vaginosis.   The mother's historical drug included Metrogel (metronidazole) for bacterial vaginosis. The mother's concomitant medications included prenatal vitamins (unspecified vitamins and minerals) for pregnancy.   The mother's last menstrual period (LMP) date was on 15-Feb-2019. Estimated delivery date (EDD) was reported as 22-Nov-2019 and corrected estimated date of delivery (CEDD) was reported as 05-Dec-2019. The type of pregnancy was singleton.   On an unspecified date in 2019, the subject's mother underwent ultrasound and no MCMs were noted.  On 23-Apr-2019, the subject's mother underwent horizon and no MCMs were noted.  On 24-Apr-2019, the subject's mother underwent spinal muscular atrophy and no MCMs were noted.  On 13-May-2019, the subject's mother underwent panorama test and no MCMs were noted.  On 27-Jun-2019, the subject's mother underwent ultrasound and no MCMs were noted.  On 25-Oct-2019, at approximately 36 weeks of gestation, the subject's mother was administered Flucelvax QIVc [influenza vaccine, subunit influenza virus vaccine polyvalent; batch number: 261218, dose: 0.5 mL, route of administration, anatomical location and expiration date: not reported] (explicitly coded as Foetal exposure during pregnancy') for influenza immunisation.   On the same day, the subject's mother underwent ultrasound and no MCMs were noted.  At approximately 39 weeks of gestation (also reported as 37 weeks of gestation), the mother delivered a live female neonate via vaginal method. The neonate's birth weight was 2400 grams, body length was 48.3 cm and head circumference was 31.8 cm. The reported appearance, pulse, grimace, activity, and respiration (APGAR) score at one minute was 8, 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.  The event of low birth weight baby was considered as serious due to criterion of medical significance.  The reporter did not provide causality assessment to Flucelvax QIVc.  This case is linked to case 201907045 (the corresponding mother case).  Company comment: Subject's mother received Flucelvax at approximately 36 weeks of gestation. A neonate of low birth weight was delivered at gestational age of 39 weeks. Causality assessment is confounded by mother's smoking. Nevertheless, causal involvement of vaccine is not excluded, therefore the event of low birth weight is assessed as possibly related to Flucelvax. Foetal exposure is assessed as unrelated to the suspect product per company's conventions.; Sender's Comments: Subject's mother received Flucelvax at approximately 36 weeks of gestation. A neonate of low birth weight was delivered at gestational age of 39 weeks. Causality assessment is confounded by mother's smoking. Nevertheless, causal involvement of vaccine is not excluded, therefore the event of low birth weight is assessed as possibly related to Flucelvax. Foetal exposure is assessed as unrelated to the suspect product per company's conventions.