Vaccine foetal exposure during pregnancy; Low birth weight of 2220 g; This is an observational study case was received on 14-Sep-2020 from other health professional and concerned a female neonate, whose mother was 28-year-old, female pregnant subject, of body weight 117.5 lbs, height 62 inches and body mass index (BMI) 21.5 enrolled in, a prospective observational safety study.  The neonates' mother's medical history was not reported. The neonates' mother's concomitant medications included Prenatal vitamin (unspecified minerals  and vitamins) for pregnancy.  The neonates' mother's obstetrical history included that she had no previous pregnancies. The neonates' mother had no maternal or paternal or history with MCMs (major congenital malformations).  The neonate's mother's last menstrual period (LMP) date was 22-Dec-2019, estimated date of delivery (EDD) and corrected estimated date of delivery (CEDD) were both reported as 27-Sep-2020. The type of pregnancy was multiple (twin pregnancy). The neonates' mother did not use tobacco, alcohol or illicit drugs during pregnancy.  On 18-Feb-2020, at gestational age of eight weeks (calculated per LMP), the neonate's mother was vaccinated with Afluria QIV (Flu Vaccine Egg Split QIV) [Influenza vaccine; dose, route of administration, anatomical location: not reported] (explicitly coded as Foetal exposure during pregnancy') for influenza immunization. The batch number was P100126099.  On the same day, the ultrasound revealed that there were no MCM and confirmed dichorionic diatomic twin pregnancy.  On 18-Mar-2020, 14-Apr-2020, 06-May-2020, 03-Jun-2020 and 01-Jul-2020, the ultrasound revealed that there were no MCM.  at gestational age of 37 weeks (as reported), the mother vaginally delivered two female neonates. The neonate's birth weight was 2220 g, body length was 47 cm and head circumference was 32 cm. APGAR (appearance, pulse, grimace, activity, and respiration) score at one minute was 8, at five minutes was 9 and no data were reported at 10 minutes. No pregnancy complications were noted. No MCM was identified at birth.  The outcome of the event 'low birth weight baby' was not reported.  The reporter did not provide a causality assessment to Afluria QIV.  The event of 'low birth weight baby' was considered to be medically significant by a Physician within Seqirus's Pharmacovigilance and Risk Management Department.  This case is linked to cases 202004473 (corresponding mother case) and 202004474 (corresponding twin case).  Company comment: The neonate's mother was vaccinated with the suspect product, Afluria QIV (explicitly coded as Foetal exposure during pregnancy'). Reportedly, six months and 19 days after vaccination, the mother vaginally delivered two female neonates. The one neonate's birth weight was low (2220 g). Chronology is unsuggestive. Causality was highly confounded by twin pregnancy. No information regarding neonate's mother medical history was provided. Considering all the above mentioned, causal relationship between the suspect product and the event of low birth weight baby is assessed as not related. Foetal exposure during pregnancy is not related per company's conventions.; Sender's Comments: The neonate's mother was vaccinated with the suspect product, Afluria QIV (explicitly coded as Foetal exposure during pregnancy'). Reportedly, six months and 19 days after vaccination, the mother vaginally delivered two female neonates. The one neonate's birth weight was low (2220 g). Chronology is unsuggestive. Causality was highly confounded by twin pregnancy. No information regarding neonate's mother medical history was provided. Considering all the above mentioned, causal relationship between the suspect product and the event of low birth weight baby is assessed as not related. Foetal exposure during pregnancy is not related per company's conventions.