Baby was delivered at gestational age of 31.9 weeks/preterm birth; Birth weight of baby was 2183 g/Low birth weight baby; Foetal exposure during pregnancy; This is a serious spontaneous case, initially received from other health professional on 20-Jun-2019, concerning a female neonate patient.   The patient's mother 20-year-old had 4 previous pregnancies that included 2 full term live births, one preterm live birth and one spontaneous abortion. The previous pregnancies did not have any history of birth defect. The patient's mother had no history of offspring with major congenital malformation. The patient's mother had no maternal or paternal history with major congenital malformation.   The current condition of the patient's mother included herpes simplex type 1 (HSV 1) from 03-Apr-2018 to ongoing. The concomitant medications of the patient's mother included Prenatal vitamins (minerals NOS, vitamins NOS) for pregnancy.     The last menstrual period (LMP) date of the patient's mother was 23-Jul-2018. The type of pregnancy was singleton. The historical condition of the patient's mother included urinary tract infection (from 10-Sep-2018 till 20-Sep-2018), bacterial vaginosis and chlamydia (from 18-Sep-2018 till 28-Sep-2018). The historical drugs of the patient's mother included Zithromax (azithromycin, 4 tablets once orally) for chlamydia, Metrogel (metronidazole, 0.75 percent twice daily vaginally) for bacterial vaginosis.    The patient's mother did not use tobacco, alcohol during pregnancy but had consumed illicit-drug (marijuana) during pregnancy for which urine drug screening was positive.  On 10-Sep-2018, the patient's mother underwent spinal muscular atrophy screen and fibrosis mutation analysis and no congenital malformation was reported. On 19-Sep-2018, the patient's mother underwent ultrasound scan and no congenital malformation was reported.  On 17-Oct-2018, approximately at gestational age of 12 weeks, the foetus was exposed to Flucelvax QIVc [Influenza vaccine, subunit influenza virus vaccine polyvalent, route of administration: transplacental, batch number: 252664, dose, expiry date and anatomical location: not reported] (explicitly coded as foetal exposure during pregnancy) for an unknown indication.   On 07-Nov-2018, the patient's mother underwent ultrasound scan and on 17-Nov-2018, the patient's mother underwent quad screen test and no congenital malformation was reported.  At gestational age of 31.9 weeks, the mother delivered female neonate (reported as premature baby) through caesarean method of delivery and preterm premature rupture of membranes was observed as pregnancy complication in mother. The birth weight of the foetus was 2183 g (reported as low birth weight baby), head circumference was 29.8 cm and length were 45.1 cm. Appearance, pulse, grimace, activity and respiration (APGAR) score at one minute was 7, at five minutes was 8 and no data was reported for APGAR score at ten minutes. No major congenital malformation was identified at birth.  The estimated date of delivery (EDD) and corrected estimated date of delivery (CEDD) of the patient's mother was reported as 29-Apr-2019.  This case is cross-linked to the case: 201904025 (mother case).; Reporter's Comments: A female neonate was considered as premature baby, delivered at gestational age of 31.9 weeks through caesarean method, 4 months 14 days after administration of Flucelvax QIV vaccine given at 12 weeks of gestation age (explicitly coded as foetal exposure during pregnancy). The birth weight of the foetus was 2183 g (low birth weight baby). Considering the unlikely temporal relationship between vaccination and reported events, no evidence for a biological mechanism that could cause the events and reported risk factors/history (HSV 1, marijuana use, 4 previous pregnancies - 2 full term live births, one preterm live birth and one spontaneous abortion, urinary tract infection, bacterial vaginosis chlamydia and  treatment drugs  azithromycin/metronidazole), the events were assessed as not related to the vaccination. The decision to administer a vaccine during pregnancy is related to medical decision making by the mother and her physician and is not related to any property of the medication. The event of foetal exposure during pregnancy was assessed as not related considering the intended use of the vaccine. The company assessed this case as serious (medically significant)