Anxiety; Streptococcus algalactiae infection; Spontaneous abortion/Miscarriage; No evidence of cervix; Vaccine exposure during pregnancy; Premature rupture of membrane; This observational study case, initially received on 16-Mar-2021 from other health professional and concerned a 34-year-old pregnant, female subject (Race: White, Ethnicity: Not Hispanic or Latino), (subject ID: 002-0447) of body weight 100 lbs, height 63.5 inches and body mass index (BMI) 17.4, enrolled in CSLCT-OBS-17-15, a prospective observational safety study on pregnancy outcomes in women immunized with Afluria QIV, a seasonal quadrivalent vaccine, during pregnancy.   The subject's concurrent conditions included decreased BMI. The subject's concomitant medications included vitamin B6 used as health supplement and Prenatal (unspecified minerals and vitamins) used as health supplement and for pregnancy.  The subject's obstetrical history included one previous pregnancy with one full term live birth. The subject had no history of offspring with major congenital malformation (MCM). Also, the subject had 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 reported as 30-Aug-2020. The subject's estimated delivery date (EDD) was reported as 06-Jun-2021 and corrected estimated date of delivery (CEDD) was reported as 22-Jun-2021. The type of pregnancy was singleton.   On 21-Oct-2020, at approximately seven weeks of gestation (calculated per LMP), the subject was vaccinated with Afluria QIV (Flu Vaccine Egg Split QIV CSL) (influenza vaccine, route of administration, anatomical location: not reported) (explicitly coded as 'Vaccine exposure during pregnancy') for an influenza immunisation. The batch number reported was P100253284.  On an unspecified day, an unknown amount of time after receiving Afluria QIV, the subject developed anxiety.  On 28-Oct-2020, the ultrasound revealed no MCM.  On 25-Nov-2020, the ultrasound revealed no MCM.  On an unspecified day in 2020, an unknown amount of time after receiving Afluria QIV, the subject developed premature rupture of membranes.  On 29-Dec-2020, two months and eight days after vaccination, at gestational age of 15 weeks (as reported), the ultrasound revealed no evidence of cervix and no MCM. Spontaneous abortion was identified. The factor that might had an impact on the foetal loss was premature rupture of membranes.  On 04-Jan-2021, 2 months 14 days after receiving Afluria QIV, the subject developed streptococcus algalactiae infection and was treated with Augmentin (amoxicillin, clavulanic acid) at a dose of 875 per 125 mg, twice a day, orally.  On 10-Jan-2021, the subject recovered from the event streptococcus algalactiae infection and stopped treatment with Augmentin.  At the time of initial reporting on 16-Mar-2021, the patient had not recovered from the event of anxiety.  The outcome for the events of 'incompetent cervix', spontaneous abortion and premature rupture of membranes was not reported.  The reporter did not provide a causality assessment.  The events of streptococcus algalactiae infection, spontaneous abortion and premature rupture of membranes were considered to be medically significant by a Physician within Risk Management Department.  Company comment: A 34-year-old, pregnant subject was vaccinated with Afluria QIV at approximately seven weeks of gestation. An unknown amount of time after receiving Afluria QIV, the subject developed anxiety. On an unspecified day in 2020, an unknown amount of time after receiving Afluria QIV, the subject developed premature rupture of membranes. Two months and eight days after vaccination, at gestational age of 15 weeks (as reported), the ultrasound revealed no evidence of cervix and no MCM. Spontaneous abortion was identified. The factor that might had an impact on the foetal loss was premature rupture of membranes. Two months 14 days after receiving Afluria QIV, the subject developed Streptococcus algalactiae infection and was treated with Augmentin. The subject's concurrent conditions included decreased BMI. The subject's obstetrical history included one previous pregnancy with one full term live birth. Causality is assessed as not related for anxiety and spontaneous abortion due to alternative aetiology. Streptococcus infection, premature rupture of membranes and Cervical incompetence are assessed as not related due to biological implausibility. Vaccine exposure during pregnancy is assessed as not related per company's conventions.; Sender's Comments: A 34-year-old, pregnant subject was vaccinated with Afluria QIV at approximately seven weeks of gestation. An unknown amount of time after receiving Afluria QIV, the subject developed anxiety. On an unspecified day in 2020, an unknown amount of time after receiving Afluria QIV, the subject developed premature rupture of membranes. Two months and eight days after vaccination, at gestational age of 15 weeks (as reported), the ultrasound revealed no evidence of cervix and no MCM. Spontaneous abortion was identified. The factor that might had an impact on the foetal loss was premature rupture of membranes. Two months 14 days after receiving Afluria QIV, the subject developed Streptococcus algalactiae infection and was treated with Augmentin. The subject's concurrent conditions included decreased BMI. The subject's obstetrical history included one previous pregnancy with one full term live birth. Causality is assessed as not related for anxiety and spontaneous abortion due to alternative aetiology. Streptococcus infection, premature rupture of membranes and Cervical incompetence are assessed as not related due to biological implausibility. Vaccine exposure during pregnancy is assessed as not related per company's conventions.