Chorioamnionitis; Vaccine foetal exposure during pregnancy; This is an observational study case, initially received from other health professional on 15-Apr-2020, concerning a male, foetal subject , whose mother was 30-year-old, pregnant, female subject of body weight: 148.6 lbs, height: 67 inches and body mass index (BMI): 23.3, 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 mother's medical history was not reported.  The subject's mother's concomitant medications included Prenatal vitamins (unspecified vitamins and minerals) for pregnancy.  The subject's mother had no previous pregnancies. The subject's mother had no maternal or paternal history with major congenital malformation (MCM).  The subject's mother's last menstrual period (LMP) date was 31-May-2019. The type of pregnancy was singleton. The mother's estimated delivery date (EDD) was 06-Mar-2020 and corrected estimated delivery date (CEDD) was not reported. The subject's mother did not consume alcohol, tobacco and illicit drugs during pregnancy. The father's age was not provided.   On 27-Jul-2019, the subject's mother underwent dating ultrasound and it was normal per reporter. No MCM was noted.  On 07-Aug-2019, the subject's mother underwent hemoglobin electrophoresis and it was negative per reporter. The subject's mother also underwent prenatal bloodwork and it was normal per reporter. No MCM was noted.  On 28-Aug-2019, the subject's mother underwent first trimester screen and it was negative per reporter. No MCM was noted.  On 09-Sep-2019, the subject's mother underwent GC chlamydia cultures and it was negative per reporter. No MCM was noted.  On 12-Sep-2019, the subject's mother underwent maternal alpha-fetoprotein (AFP) and it was negative per reporter. No MCM was noted.  On 10-Oct-2019, at gestational age of 18 weeks (calculated per LMP), the subject's mother was administered Afluria QIV (Flu Vaccine Egg Split QIV CSL) [influenza vaccine, batch number: P100123038, dose, route of administration, anatomical location and expiration date: not reported] (explicitly coded as 'foetal exposure during pregnancy') for influenza immunisation.   On the same day, the subject's mother underwent anatomic san and it was normal per reporter. No MCM was noted.  On an unknown date, an unknown amount of time after vaccination, the pregnancy was complicated with chorioamnionitis.  At gestational age of 39.3 weeks (as reported), the subject's mother delivered a male neonate by low transverse caesarean section due to failure to progress. The birth weight of subject was 3728 g, head circumference was 34 cm and length were 50.8 cm. Appearance, pulse, grimace, activity and respiration (APGAR) score at one minute was 9 and at five minutes was 9 as well. APGAR score for 10 minutes was not provided. No MCM was identified at birth.   At the time of this report, the outcome of chorioamnionitis was not reported.  Per company, the event of chorioamnionitis was considered serious due to the criterion of medical significance.  This reporter did not provide a causality assessment to Afluria QIV.  This case is linked to case 202002954 (the corresponding mother case).  Company comment: A foetal subject experienced amniotic cavity infection an unknown amount of time after foetal exposure to Afluria QIV. The subject's mother was administered vaccine at 18 weeks of gestation. Chronology needs more clarification. More information regarding medical history and diagnostic findings is needed. Causal role of the suspect vaccine is unassessable. Foetal exposure during pregnancy assessed as not related per company's conventions.; Sender's Comments: A foetal subject experienced amniotic cavity infection an unknown amount of time after foetal exposure to Afluria QIV. The subject's mother was administered vaccine at 18 weeks of gestation. Chronology needs more clarification. More information regarding medical history and diagnostic findings is needed. Causal role of the suspect vaccine is unassessable. Foetal exposure during pregnancy assessed as not related per company's conventions.