Bronchitis; Bacterial vaginosis; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 02-Jan-2020, concerning a 30-year-old female, pregnant subject, of body weight 114 lbs, height 61.2 in and body mass index (BMI) 21.4, enrolled in a prospective observational safety study on pregnancy outcomes in women immunized with Afluria QIV, a seasonal quadrivalent vaccine, during pregnancy.  The subject's relevant medical history included bacterial vaginosis.   The subject's concomitant medications included: Prenatal vitamins (unspecified vitamins and minerals) for healthy pregnancy and Metrogel (metronidazole) for bacterial vaginosis.   The subject had no previous pregnancies. The subject had no history of offspring with major congenital malformation (MCM) and no maternal or paternal history with MCM. The subject did not use tobacco, alcohol or illicit drugs during pregnancy.   The subject's last menstrual period (LMP) date was 01-Aug-2019. The subject's estimated delivery date (EDD) was reported as 07-May-2020 and corrected estimated date of delivery (CEDD) was not reported. The type of pregnancy was singleton.  On 09-Sep-2019, at approximately five weeks of gestation (calculated per LMP), the subject was administered Afluria QIV (Flu Vaccine Egg Split QIV CSL) [influenza vaccine, batch number: P100110950, dose, expiration date, route of administration and anatomical location: not reported] (explicitly coded as 'Vaccine exposure during pregnancy') for an influenza immunization.  On 07-Oct-2019, the subject underwent cystic fibrosis mutation analysis and no MCM was noted.   On 21-Oct-2019, the subject underwent first trimester screening and no MCM was noted.   On 04-Nov-2019, 1 month and 26 days after vaccination, the subject experienced recurrence of bacterial vaginosis and was treated with terconazole at dose of 0.4 %, every day, vaginally.  On 11-Nov-2019, treatment with terconazole was stopped.  On 02-Dec-2019, the subject underwent second trimester screening and no MCM was noted. On the same day, the event of bacterial vaginosis was resolved.  On an unspecified date, an unknown amount of time after vaccination, the subject developed bronchitis.  On 18-Jan-2020, the subject started treatment with Zithromax (azithromycin) for bronchitis, at dose of 250 mg, two pills first day and than one pill for four days, orally.   On 22-Jan-2020, the treatment with Zithromax was stopped.  On 03-Feb-2020, the subject underwent one hour glucola test (1HGCT) and no MCMc were noted.  On 24-Mar-2020, the subject underwent group B strep (GBS) test and no MCMc were noted.  At the time of this report, the outcome of event bronchitis was not reported.  The event of 'bronchitis bacterial' was assessed as serious, due criterion of medical significance, per company.  The reporter did not provide causality assessment to Afluria QIV.  Follow up information received from other health professional on 12-Feb-2020: Medical history was updated. Start and stop date added and outcome changed from not reported to resolved for bacterial vaginosis. Narrative was amended accordingly.  Follow up received from other health professional on 02-Apr-2020: Two lab tests were added (1HGCT and group B strep (GBS) test). Bronchitis was added as event and Zithromax was added as treatment medication. The case upgraded to serious due to bronchitis. The narrative was amended accordingly.  Company comment: The patient experienced bacterial vaginosis 1 month 26 days after receiving Flu Vaccine Egg Split QIV CSL. Chronology is unsuggestive. Moreover, patient's relevant medical history includes bacterial vaginosis. The subject also developed bronchitis, an unknown amount of time after vaccination. Chronology needs more clarification. However, causal role of the suspect vaccine cannot be excluded and is assessed as unlikely related to the event bronchitis bacterial (defaults to "related" in the safety database for reporting purposes). Causality is not related for bacterial vaginosis. Vaccine exposure during pregnancy assessed as not related per company's conventions.; Sender's Comments: The patient experienced bacterial vaginosis 1 month 26 days after receiving Flu Vaccine Egg Split QIV CSL. Chronology is unsuggestive. Moreover, patient's relevant medical history includes bacterial vaginosis. The subject also developed bronchitis, an unknown amount of time after vaccination. Chronology needs more clarification. However, causal role of the suspect vaccine cannot be excluded and is assessed as unlikely related to the event bronchitis bacterial (defaults to "related" in the safety database for reporting purposes). Causality is not related for bacterial vaginosis. Vaccine exposure during pregnancy assessed as not related per company's conventions.