Polyhydramnios third semester; Foetal exposure during pregnancy; This is an observational study case, initially received from other health professional on 27-Nov-2019, concerning a female neonatal subject whose mother was 26-year-old pregnant, female subject of body weight: 140 Ibs, height: 56 in and body mass index (BMI) 31.4  enrolled in a prospective observational safety study. The subject's father was 26-year-old.  The subject's mother had two previous pregnancies, one was spontaneous abortion and one was full term live birth 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 did not use tobacco, alcohol or illicit drugs during pregnancy.  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-Mar-2019. Estimated delivery date (EDD) was reported as 20-Dec-2019 and corrected estimated date of delivery (CEDD) was reported as 28-Nov-2019. The type of pregnancy was singleton.   On 29-Jul-2019, the subject's mother underwent spinal muscular atrophy, panorama, fragile X and cystic fibrosis mutation analysis. No MCMs noted.  On 22-Aug-2019, the subject's mother underwent ultrasound and no MCMs were noted.  On 17-Oct-2019, at approximately 30 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: 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.  On 07-Nov-2019, the subject's mother underwent ultrasound and no MCMs were noted.  At approximately 39.1 weeks of gestation, the mother delivered a live female neonate via caesarean method. The neonate's birth weight was 3470 grams, body length was 51.4 cm and head circumference was 36.2 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. Pregnancy status was collected and polyhydramnios was noted as pregnancy complication.  At the time of initial reporting, the outcome for the event of polyhydramnios was not reported.  The event of polyhydramnios was considered as serious due to criterion of medical significance per company.  The reporter did not provide causality assessment to Flucelvax QIVc.  This case is linked to case number 201907060 (corresponding mother case).  Company Comment: The female neonatal subject experienced polyhydramnios after foetal exposure during pregnancy (at approximately 30 weeks of gestation) with the suspect product Flucelvax QIV. Chronology is plausible. Mother's medical history of obesity (body mass index 31.4) may have contributed to development of the event. Foetal exposure during pregnancy is assessed as not related per company's conventions. For the event polyhydramnios, causal role of the suspect product cannot be totally excluded and is assessed as possibly related.; Sender's Comments: The female neonatal subject experienced polyhydramnios after foetal exposure during pregnancy (at approximately 30 weeks of gestation) with the suspect product Flucelvax QIV. Chronology is plausible. Mother's medical history of obesity (body mass index 31.4) may have contributed to development of the event. Foetal exposure during pregnancy is assessed as not related per company's conventions. For the event polyhydramnios, causal role of the suspect product cannot be totally excluded and is assessed as possibly related.