Foetal exposure during pregnancy; Low birth weight; This is an observational study case, initially received from other health professional on 05-Aug-2019, concerning a female neonate subject, whose mother was a 29-year-old female of body weight: 137.2 lbs, height: 65 inches and body mass index (BMI): 22.8, enrolled in a prospective observational safety study.  The subject's mother current conditions included hypothyroidism and anxiety.  The subject's mother concomitant medications included Prenatal vitamins (vitamins not otherwise specified (nos), mineral (nos)) as supplement, sertraline for anxiety and levothyroxine for thyroid.  The subject mother's obstetrical history noted that mother had two previous pregnancies with one full term live birth and one spontaneous abortion. The subject's mother had no history of offspring with major congenital malformation (MCM) and no relevant maternal and paternal medical history. The subject's mother did not use tobacco, alcohol or illicit drugs during pregnancy.   The subject's mother last menstrual period (LMP) date was 14-Oct-2018. Estimated delivery date (EDD) was 22-Jul-2019 and corrected delivery date (CEDD) was 21-Jul-2019. The pregnancy was singleton and complicated with pre-eclampsia. The subject's father was 28-year-old.  On 10-Dec-2018, at approximately eight weeks of gestation, the subject's mother received Afluria QIV(Flu Vaccine Egg Split QIV CSL) [Influenza Vaccine, does, route of administration, anatomical location, batch number and expiration date: not reported] (explicitly coded as 'foetal exposure during pregnancy') for influenza immunization. On the same day, the subject's mother underwent ultrasound, and no MCM was noted.  On 08-Jan-2019, the subject's mother underwent inheritest, sequential 1 and nuchal translucency tests, and no MCM was noted.  On 05-Feb-2019, the subject's mother underwent sequential 2 test, and no MCM was noted.  At gestational age of 37 weeks, the subject's mother delivered female neonate via caesarean method. The neonate's birth weight was 2381 grams, her head circumference and body length were not reported. The appearance, pulse, grimace, activity, and respiration (APGAR) scores were 8 at one minute and 9 at five minutes. APGAR score was not reported for 10 minutes. There was no MCM identified at birth.   At the time of this report, the outcome of the event 'low birth weight baby' was not reported.  This case is linked to case 201903903, the corresponding maternal pregnancy report.  Follow up received from other health professional on 04-Feb-2020: Eclampsia removed, and pre-eclampsia was added as mother's pregnancy complication. The narrative was amended accordingly.  Company comment: A neonate subject experienced low birth weight after his mother was vaccinated with Flu Vaccine Egg Split QIV CSL.  Considering latency period between exposure to the product and occurrence of the event, chronology is unsuggestive. The subject was born during 37 week of gestation which also may have impacted on the low birth weight. The medical history of the patient's mother (experienced eclampsia during pregnancy and existing hypothyroidism) along with maternal age (40 years old) may have contributed in developing this event. With information provided causality is assessed as not related to the product.; Sender's Comments: A neonate subject experienced low birth weight after his mother was vaccinated with Flu Vaccine Egg Split QIV CSL.  Considering latency period between exposure to the product and occurrence of the event, chronology is unsuggestive. The subject was born during 37 week of gestation which also may have impacted on the low birth weight. The medical history of the patient's mother (experienced eclampsia during pregnancy and existing hypothyroidism) along with maternal age (40 years old) may have contributed in developing this event. With information provided causality is assessed as not related to the product.