Delivery at 34.4 weeks of gestation; Anemia; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 03-Apr-2020, concerning a 30-year-old, pregnant, female subject of body weight: 225 lbs, height: 62 inches and body mass index (BMI): 41.1, enrolled in, a prospective observational safety study.  The subject's medical history included Obesity, hypertension, herpes simplex virus 2 (HSV2), and renal disease.  The subject's concomitant medications included Prenatal vitamins (unspecified vitamins and minerals) for pregnancy.   The subject's obstetrical history included two previous pregnancies, one full term live birth and one spontaneous abortion. 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, alcohol or illicit drugs during pregnancy.   The subject's last menstrual period (LMP) date was on 10-Aug-2019. The type of pregnancy was singleton. The subject's estimated delivery date (EDD) were reported as 17-May-2020 and corrected estimated date of delivery (CEDD) were reported as 05-May-2020.   On 07-Oct-2019, the subject underwent cystic fibrosis mutation analysis and spinal muscular atrophy and no MCMs were noted.   On 14-Oct-2019, approximately at 9 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] (explicitly coded as 'Vaccine exposure during pregnancy') for an influenza immunization.  On the same day, the subject underwent ultrasound and no MCMs were noted.   On 29-Oct-2019, the subject underwent panorama and no MCMs were noted.   On 01-Nov-2019, the subject underwent ultrasound and no MCMs were noted.   On 22-Nov-2019, the subject underwent ultrasound and no MCMs were noted.   On 19-Dec-2019, the subject underwent ultrasound and no MCMs were noted.   On 31-Jan-2020, 3 months and 17 days after vaccination, the subject developed anaemia and started treatment with oral ferrous sulfate at dose of 325 mg, administered via oral route three times a day.  On 03-Mar-2019, the subject underwent ultrasound and no MCMs were noted.   On 10-Mar-2019, the subject underwent ultrasound and no MCMs were noted.   On 15-Mar-2019, the subject underwent ultrasound and no MCMs were noted.   On 19-Mar-2019, the subject underwent ultrasound and no MCMs were noted.   On 20-Mar-2019, the subject underwent ultrasound and no MCMs were noted.   On unknown date, the pregnancy status was collected, and pregnancy was complicated with chronic hypertension.  On 27-Mar-2020, at gestational age of 34.4 weeks (as reported), the subject delivered a preterm live birth, female neonate by caesarean method. The neonate's birth weight was 1955 grams. The neonate's head circumference were 31.1 cm and body length were 44.5 cm. The appearance, pulse, grimace, activity, and respiration (APGAR) scores were 8 at one minute and 9 at five minutes. APGAR score for 10 minutes was not reported. No MCMs were identified at the time of birth.  On the same day, the subject finished treatment and the outcome of event anemia' was resolved.  At the time of this report, the outcome of event premature delivery' was not reported.  The event of premature delivery' was considered serious due to criterion of medical significance, per company.  The reporter did not provide causality assessment.   This case is linked to 202002757 (the corresponding baby case).  Company comment: A pregnant subject experienced preterm delivery, five months and 13 days after receiving Flucelvax QIV. The subject also developed anaemia three months and 17 days after vaccination. Chronology is unsuggestive. The subject's medical history included obesity, hypertension, herpes simplex virus 2 (HSV2), and renal disease. Anaemia is common during pregnancy. Causality was confounded. Causal role of the suspect vaccine is assessed as not related for both events. Vaccine exposure during pregnancy assessed as not related per company's conventions.; Sender's Comments: A pregnant subject experienced preterm delivery, five months and 13 days after receiving Flucelvax QIV. The subject also developed anaemia three months and 17 days after vaccination. Chronology is unsuggestive. The subject's medical history included obesity, hypertension, herpes simplex virus 2 (HSV2), and renal disease. Anaemia is common during pregnancy. Causality was confounded. Causal role of the suspect vaccine is assessed as not related for both events. Vaccine exposure during pregnancy assessed as not related per company's conventions.