Bacterial vaginosis; Anemia; Chlamydia; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 12-Jul-2019, concerning a 20-year-old adult female pregnant subject of weight 200 lbs, 64 inches height and body mass index (BMI) 34.3, 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 had no previous pregnancies. On an unknown date, the subject's family history of major congenital malformation was collected, and the subject had no maternal/paternal history with major congenital malformations. The subject did not use tobacco, alcohol or illicit drugs during pregnancy.  On an unknown date, the pregnancy status of the subject was collected, and no pregnancy complications were noted.  The subject's concomitant medication included Prenatal vitamins (vitamins NOS; Minerals NOS) for pregnancy.    The subject's last menstrual period date was 24-Jul-2018. The type of pregnancy was singleton.  On 24-Oct-2018, at 13 weeks of gestation, the pregnant subject was administered Flu Vaccine Cell Subunit QIV NVD (Influenza vaccine, subunit influenza virus vaccine polyvalent; batch number: 252664, dose, route of administration, expiry date and anatomical location: not reported) for an unknown indication (explicitly coded as vaccine exposure during pregnancy).  On the same day after vaccination, the subject developed chlamydia and was treated with Zithromax (azithromycin) [dose: 1000 mg, frequency: one time a day (od), route of administration: oral, stop date: 24-Oct-2018]. On 25-Oct-2018, the subject underwent ultrasound scan and no major congenital malformation was noted.  On an unspecified date, the subject developed bacterial vaginosis and was treated with Metrogel [metronidazole; start date: 01-Nov-2018, stop date: 11-Nov-2018, route of administration: vaginal, dose: 0.75 percent, frequency: twice a day (bid)].   On 26-Nov-2018, the subject underwent ultrasound scan and no major congenital malformation was noted.  On 26-Jan-2019, 3 months 2 days after vaccination, the subject developed anaemia and was eventually treated with Ferrous sulphate [start date: 26-Jan-2019, stop date: 30-Apr-2019, route of administration: oral, dose: 1 tablet, frequency: twice a day (bid)].  On 08-Mar-2019, the subject underwent ultrasound scan and no major congenital malformation was noted.  On 30-Apr-2019, the patient had recovered from the event anaemia. The outcome of the events bacterial vaginosis and chlamydia were not reported.  The subject delivered a full-term female neonate at 40 weeks gestation. The neonate's birth weight was 3402 grams, head circumference was 33 cm and body length were 53.3 cm. The APGAR scores were 8 (one minute) and 9 (five minutes). APGAR score was not reported for 10 minutes. There was no major congenital malformation was noted.  The subject's estimated date of delivery was reported as 30-Apr-2019.; Reporter's Comments: A 20-year-old female pregnant subject was diagnosed with chlamydial infection, on the same day after receipt of Flu Vaccine Cell Subunit QIV (considered as vaccine exposure during pregnancy). The subject developed bacterial vaginosis, unspecified period post vaccination. Considering the infective origin of these events, the casual role of study vaccine is ruled out. Hence, causality assessed as not related. The subject was diagnosed with anaemia, more than 3 months post vaccination. The pregnancy state of the subject provide more plausible explanation rather than study vaccine. Hence, causality assessed as not related to study vaccine. The event vaccine exposure during pregnancy assessed as not related, considering the intended use of the vaccine. The company assessed the case as serious (medically significant)