Progression of labor; Preterm premature rupture of membranes; Delivery at 33.6 weeks of gestation; Vaccine exposure during pregnancy; This is an observational study case, initially received from other health professional on 25-Mar-2020, concerning a 37-year-old, pregnant female subject, of body weight: 132 lbs, height: 65 inches and body mass index (BMI): 22, enrolled in a prospective observational safety study.   The subject's medical history was not reported. It was noted that the subject had advanced maternal age.  The subject's concomitant medications included multivitamins (vitamins nonspecific) as vitamin supplementation, and Tdap (diphtheria vaccine toxoid, pertussis vaccine acellular, tetanus vaccine toxoid) as vaccination.  The subject's obstetrical history noted that the subject had one previous full-term live birth. The subject had no history of offspring with major congenital malformation (MCM). The subject had no relevant maternal or paternal medical history. The subject did not use tobacco, illicit drugs or alcohol during pregnancy.  The subject's last menstrual period (LMP) date was reported as 09-Jul-2019. The subject's estimated delivery date (EDD) and corrected estimated date of delivery (CEDD) were reported as 14-Apr-2020. The type of pregnancy was singleton.   On 17-Sep-2019, at approximately ten weeks of gestation (calculated per LMP), the subject was administered Flucelvax QIVc (Flu Vaccine Cell Subunit QIV NVD) [influenza vaccine, subunit influenza virus vaccine polyvalent; dose: 0.5 ml, batch number: 261200, anatomical location, route of administration and expiration date: not reported] (explicitly coded as Vaccine exposure during pregnancy') for influenza immunisation.   On the same day, the subject underwent Maternit 21 test, and no MCM was noted.  On 15-Oct-2019, the subject underwent ultrasound, and no MCM was noted.  On 30-Oct-2019, the subject underwent maternal serum alpha-fetoprotein screening (MSAFP/serum markers), and no MCM was noted.  On 20-Nov-2019, the subject underwent anatomy ultrasound, and no MCM was noted.  On an unspecified date, an unknown amount of time after vaccination, the subject's pregnancy status was collected, and it was noted that the pregnancy was complicated with preterm premature rupture of membranes and progression of labor.  At gestational age of 33.6 weeks (as reported), the subject vaginally delivered live birth male neonate. The neonate's birth weight was 2240 g, while head circumference and length were not provided. The appearance, pulse, grimace, activity and respiration (APGAR) scores were 8 (one minute), 9 (five minutes), and APGAR score for ten minutes was not reported. There were no major MCMs identified at birth.  At the time of this report, the outcome of the events preterm labor', 'precipitate labor' and 'preterm premature rupture of membranes' was not reported.  The events of 'preterm labor', 'precipitate labor' and 'preterm premature rupture of membranes' were assessed as serious due to criteria of medical significance, per company.   The reporter did not provide causality assessment.  This case is linked to the case 202002619, the corresponding baby case.  Company comment: A 37-year-old pregnant female subject developed premature labour, precipitate labour, preterm premature rupture of membranes after vaccination with the suspect product Afluria Quadrivalent for influenza immunisation. Reportedly, at gestational age of 33.6 weeks (as reported) the delivery occurred. Chronology seems compatible. On 15-Oct-2019, a month after vaccination, the subject underwent ultrasound, and no MCM was noted. The subject's medical history was not reported. It was noted that the subject had advanced maternal age. The subject's concomitant medications included multivitamins (vitamins nonspecific) as vitamin supplementation, and Tdap (diphtheria vaccine toxoid, pertussis vaccine acellular, tetanus vaccine toxoid) as vaccination. With information presented, causality is assessed as unlikely related for all events (except for Exposure during pregnancy which is assessed as not related per company conventions) considering concomitant medications, advanced maternal age and ultrasound analysis.; Sender's Comments: A 37-year-old pregnant female subject developed premature labour, precipitate labour, preterm premature rupture of membranes after vaccination with the suspect product Afluria Quadrivalent for influenza immunisation. Reportedly, at gestational age of 33.6 weeks (as reported) the delivery occurred. Chronology seems compatible. On 15-Oct-2019, a month after vaccination, the subject underwent ultrasound, and no MCM was noted. The subject's medical history was not reported. It was noted that the subject had advanced maternal age. The subject's concomitant medications included multivitamins (vitamins nonspecific) as vitamin supplementation, and Tdap (diphtheria vaccine toxoid, pertussis vaccine acellular, tetanus vaccine toxoid) as vaccination. With information presented, causality is assessed as unlikely related for all events (except for Exposure during pregnancy which is assessed as not related per company conventions) considering concomitant medications, advanced maternal age and ultrasound analysis.