Dysmature placenta; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 06-Apr-2020, concerning a 30-year-old, female pregnant subject of body weight: 135 lbs, height: 64 inches and body mass index (BMI): 23.2, enrolled in a prospective observational safety study.  The subject's medical history was not provided.  The subject's concomitant medication included Prenatal vitamins (unspecified vitamins and minerals) for pregnancy.  The subject's obstetrical history included two previous pregnancies, both with full-term live births. The subject had no history of offspring with major congenital malformation (MCM) and no relevant maternal and paternal medical history. The subject did not use tobacco or alcohol during pregnancy. The urine drug screen was positive for marijuana and cocaine.  The subject's last menstrual period (LMP) date was 28-Mar-2019. The type of pregnancy was singleton. The subject's estimated delivery date (EDD) and corrected estimated date of delivery (CEDD) weere reported as 02-Jan-2020.  On 06-May-2019, the subject underwent horizon test, no MCM was noted.  On 30-May-2019, 27-Jun-2019 and 22-Jul-2019, the subject underwent ultrasound scan, no MCM was noted.  On 22-Jul-2019, the subject ubderwent panorama test, no MCM was noted.  On 14-Oct-2019, approximately at 28 weeks of gestation (calculated per LMP), the subject was administered Flucelvax (Flu Vaccine Cell Subunit QIV NVD) [influenza vaccine, subunit influenza virus vaccine polyvalent, batch number: 261218, dose: 0.5 ml, route of administration, anatomical location and expiration date: not reported] for an influenza immunization (explicitly coded as 'Vaccine exposure during pregnancy').  On 07-Nov-2019, the subject underwent ultrasound scan, no MCM was noted.  On 15-Nov-2019, the subject's pregnancy status was collected, and it was noted that the pregnancy was complicated with dysmature placenta.  On 20-Nov-2019, 27-Nov-2019, 06-Dec-2019, 13-Dec-2019 and 19-Dec-2019, the subject underwent ultrasound scan, no MCM was noted.  Approximately at 39 weeks of gestation (as reported), the subject delivered an female neonate by vaginal method of delivery. The neonate's birth weight was 3645 grams, body length: 45.7 cm, head circumference: 34.3 and the appearance, pulse, grimace, activity, and respiration (APGAR) scores at one minute: 8, five minutes: 9 and ten minutes: not reported. There was no MCM identified at birth.   On the same day, the outcome of the event dysmature placenta was resolved.  The event of placental disorder' was assessed as serious due to criteria of medical significance, per company.  The reporter did not provide causality assessment to Flucelvax QIV.  Company comment: A pregnant subject experienced placental disorder (dysmature placenta), a month after receiving Flucelvax QIV at 28 weeks of gestation. Chronology is unsuggestive, since placenta is fully formed by 18 to 20 weeks. For the event placental disorder, causal role of the suspect vaccine is assessed as not related. Vaccine exposure during pregnancy assessed as not related per company's conventions.; Sender's Comments: A pregnant subject experienced placental disorder (dysmature placenta), a month after receiving Flucelvax QIV at 28 weeks of gestation. Chronology is unsuggestive, since placenta is fully formed by 18 to 20 weeks. For the event placental disorder, causal role of the suspect vaccine is assessed as not related. Vaccine exposure during pregnancy assessed as not related per company's conventions.