Pre-eclampsia; Low-lying placenta; Preterm birth; Vaccine exposure during pregnancy; This is an observational study case initially received from other health professional on 21-Oct-2019, concerning a 37-year-old female, pregnant subject of body weight 121 lbs, height 61 in and body mass index (BMI) 22.9, enrolled in a prospective observational safety study.   The subject's relevant medical history included acid reflux and advanced maternal age.   The subject's concomitant medications included: Prenatal and DHA (docosahexaenoic acid) vitamins (ascorbic acid, betacarotene, calcium carbonate, colecalciferol, docosahexaenoic acid, ferrous fumarate, folic acid, nicotinamide, pyridoxine hydrochloride, riboflavin, thiamine mononitrate, tocopheryl acetate, vitamin b12 nos, zinc oxide), iron, vitamin D3 and omeprazole for acid reflux.  The subject's obstetrical history included one previous pregnancy which ended with elective abortion. The subject had no history of offspring with major congenital malformation (MCM) and no relevant 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 06-Mar-2019. The subject's estimated date of delivery (EDD) was reported as 11-Dec-2019 and corrected EDD (CEDD) was reported as 31-Dec-2019. The type of pregnancy was singleton.   On 04-Jun-2019, the subject underwent ultrasound scan and no MCM was noted.  On 07-Aug-2019, the subject underwent maternal serum alpha fetoprotein (MSAFP)/serum markers test and no MCM was noted.  On 06-Sep-2019, the subject underwent foetal echo test and no MCM was noted.  On 30-Sep-2019, at approximately 26 weeks and 6 days of gestation, the subject was administered Flu Vaccine Egg Split QIV CSL (Afluria QIV) [influenza vaccine, batch number: P100118566, dose, expiration date, route of administration, anatomical location: not reported] (explicitly coded as 'Vaccine exposure during pregnancy') for influenza immunization.  At 35.3 weeks of gestation, the subject gave live birth to male neonate by caesarean method. The neonate's body weight was 2410 grams, head circumference 33 cm and length 45 cm.  The appearance, pulse, grimace, activity, and respiration (APGAR) scores were 8 (one minute) and 9 (five minutes). No data was provided for Apgar score in 10 minutes. There was no major congenital malformation identified at birth. The pregnancy complications were noted as severe pre-eclampsia and low-lying placenta.   The outcome of the events 'pre-eclampsia', 'premature delivery' and 'placenta praevia' was not reported.  The events of 'pre-eclampsia', 'premature delivery' and 'placenta praevia' were considered serious due to the criteria of medical significance, per company.   The causality assessment was not provided.    This case is linked to 201907404 (corresponding child case).  Follow up received from other health professional on 18-Dec-2019: Occupation deleted. Pregnancy information added. Facility type changed. Gestational period at exposure for concomitant medications and suspect product changed. Omeprazole added as concomitant medication. Three new events added 'low-lying placenta', 'premature delivery' and 'pre-eclampsia'. Outcome of 'vaccine exposure during pregnancy' changed to recovered/resolved and stop date updated. Narrative amended accordingly.  Company comment: The subject experienced placenta praevia, pre-eclampsia and premature delivery associated with administration of Afluria QIV. The patient was administered vaccine at approximately 26 weeks of gestation. Chronology is plausible. For the event placenta praevia, chronology does not seem plausible and causality is assessed as not related. Although causality for all events was confounded by advanced maternal age, causal role of the suspect vaccine cannot be totally excluded and is assessed as related for pre-eclampsia and premature delivery. Vaccine exposure during pregnancy is assessed as unrelated per company's conventions.; Sender's Comments: The subject experienced placenta praevia, pre-eclampsia and premature delivery associated with administration of Afluria QIV. The patient was administered vaccine at approximately 26 weeks of gestation. Chronology is plausible. For the event placenta praevia, chronology does not seem plausible and causality is assessed as not related. Although causality for all events was confounded by advanced maternal age, causal role of the suspect vaccine cannot be totally excluded and is assessed as related for pre-eclampsia and premature delivery. Vaccine exposure during pregnancy is assessed as unrelated per company's conventions.