Polyhydramnios; Foetal exposure during pregnancy; This is an observational study case, initially received from other health professional on 28-Jan-2020, concerning a foetal subject whose mother was 30-year-old pregnant, female subject of body weight: 154.6 Ibs, height: 64 in and body mass index (BMI) 26.5 enrolled in, a prospective observational safety study on pregnancy.  The subject's mother current medical condition included gastroesophageal reflux disease.  The subject's mother's concomitant medications included Prenatal (unspecified vitamins and minerals) as neonatal care.  The subject's mother obstetrical history noted that the mother had three previous pregnancies, which included one preterm live birth 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 did not use tobacco, alcohol or illicit drugs during pregnancy.              The subject's mother last menstrual period (LMP) date was on 06-Jul-2019, the estimated delivery date (EDD) was reported as 11-Apr-2020, while corrected estimated date of delivery (CEDD) was reported as 10-Apr-2020. The type of pregnancy was singleton. Subject's father was 33 years old.  On 05-Sep-2019, the subject's mother underwent ultrasound and no MCMs were noted.  On 03-Oct-2019, at approximately 12 weeks of gestation, the subject's mother was administered Flucelvax QIVc (Flu Vaccine Cell Subunit QIV NVD) [influenza vaccine, subunit influenza virus vaccine polyvalent; batch number: 261207, 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 first trimester screen and no MCMs were noted.  On an unspecified date, the mother's pregnancy status was collected, and polyhydramnios was noted. No further details were provided.  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.  This case is linked to case number 202001322 (the corresponding mother case).  Company Comment: The neonate subject was diagnosed with polyhydramnios after foetal exposure during pregnancy at approximately 12 weeks of gestation with the suspect product, Flucelvax QIV. Chronology is plausible. Pregnant state may provide alternative aetiology for the event. Foetal exposure during pregnancy is assessed as not related per company's conventions. Considering all the above mentioned, causality between suspect product and the event polyhydramnios is assessed as unlikely related (defaults to related for reporting purposes).; Sender's Comments: The neonate subject was diagnosed with polyhydramnios after foetal exposure during pregnancy at approximately 12 weeks of gestation with the suspect product, Flucelvax QIV. Chronology is plausible. Pregnant state may provide alternative aetiology for the event. Foetal exposure during pregnancy is assessed as not related per company's conventions. Considering all the above mentioned, causality between suspect product and the event polyhydramnios is assessed as unlikely related (defaults to related for reporting purposes).