Low lying placenta; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 26-Mar-2020, concerning a 22-year-old female, pregnant subject, of body weight: 172 lbs, height: 62 inches and body mass index (BMI): 31.5, who was enrolled in, a prospective observational safety study on pregnancy outcomes in women immunized with seasonal cell culture influenza trivalent (TIVc) or quadrivalent (QIVc) vaccine during pregnancy. The subject's current conditions included herpes simplex virus 1 and 2 and increased BMI. The subject's concomitant medications included Prenatal vitamins (unspecified minerals and vitamins) for pregnancy and Valtrex (valaciclovir hydrochloride) for herpes simplex virus 1 and 2. The subject's obstetrical history included one previous full term live birth. The subject had no offspring with major congenital malformation (MCM), nor relevant maternal and paternal history. The subject did not consume tobacco, alcohol or illicit drugs during pregnancy. The subject's last menstrual period (LMP) was on 18-Jan-2019. The type of pregnancy was singleton. The subject's estimated delivery date (EDD) was 25-Oct-2019 and corrected EDD (CEDD) was 19-Dec-2019. On 10-Jun-2019, the subject underwent cystic fibrosis mutation analysis and spinal muscular atrophy test. No MCM was noted. On 16-Jul-2019, the subject underwent ultrasound and panorama test. No MCM was noted. On 11-Oct-2019, at gestational age of 38 weeks (calculated per LMP), the subject received Flucelvax QIVc (Flu Vaccine Cell Subunit QIV NVD) [influenza vaccine, subunit influenza virus vaccine polyvalent, batch number: reported as 262218', dose, route of administration, anatomical location and expiry date: not reported] (explicitly coded as Vaccine exposure during pregnancy') for influenza immunisation.  On the same day, low lying placenta was noted. The subject underwent ultrasound and no MCM was noted.  On 31-Oct-2019, the subject underwent ultrasound and no MCM was noted.  On 12-Dec-2019, at gestational age of 39.7 weeks (as reported), the subject vaginally delivered a male neonate. The birth weight of the neonate was 3572 g, head circumference was 34.3 cm and length was 50.8 cm. Appearance, pulse, grimace, activity and respiration (APGAR) score at one minute was 8 and at five minutes was 9. APGAR score at ten minutes was not provided No MCM was identified at birth.   The outcome of the event low lying placenta was resolved, on 12-Dec-2019.  The event of low lying placenta was considered serious due to the criterion of medical significance, per company.  The reporter did not provide a causality assessment to Flucelvax QIV.  Company comment: Placenta praevia was noted on the same day when Flucelvax QIVc was administered. Vaccine was administered at 38 weeks of gestation. Chronology is implausible. Causal role of the suspect vaccine is assessed as not related. Vaccine exposure during pregnancy is assessed as unrelated per company's conventions.; Sender's Comments: Placenta praevia was noted on the same day when Flucelvax QIVc was administered. Vaccine was administered at 38 weeks of gestation. Chronology is implausible. Causal role of the suspect vaccine is assessed as not related. Vaccine exposure during pregnancy is assessed as unrelated per company's conventions.