Single umbilical artery; Foetal exposure during pregnancy; This is an observational study case, initially received from other health professional on 27-Feb-2020, concerning a foetus whose mother was a 34-year-old, pregnant female subject  of body weight: 182 lbs, height: 67 inches and body mass index (BMI): 28.5, enrolled in a prospective observational safety study.  The subject's mother's current condition included increased BMI, acid reflux, chronic hypertension and advanced maternal age. The subject's mother's concomitant medications included Aspirin (acetylsalicylic acid) for chronic hypertension, omeprazole for acid reflux and Prenatal vitamins (minerals nos, vitamins nos) for pregnancy.  The subject's mother obstetrical history included one previous pregnancy with spontaneous abortion. The subject's mother had no history of offspring with major congenital malformation (MCM) and no relevant maternal and paternal medical history. The subject's mother used cigarettes during pregnancy, number of products used reported as unknown, but did not use alcohol or illicit drugs.   The subject's mother's last menstrual period (LMP) date was 12-Jan-2019. The type of pregnancy was singleton. The subject's mother estimated delivery date (EDD) was reported as 19-Oct-2019 and corrected estimated date of delivery (CEDD) was reported as 01-Nov-2019.   On 22-Apr-2019, the mother underwent non-invasive prenatal testing (NIPT), ultrasound and nuchal translucency and no MCM was noted.   On 20-May-2019, the mother underwent MSAFP (maternal alpha-fetoprotein) /serum markers test and no MCM was noted.   On 03-Oct-2019, at approximately 36 weeks of gestation, the subject's mother was administered Afluria QIV (Flu Vaccine Egg Split QIV CSL) [influenza vaccine, batch number: P100112488, dose, route of administration, anatomical location and expiration date: not reported] (explicitly coded as Foetal exposure during pregnancy') for an influenza immunization.  On an unspecified date in 2019, the subject developed single umbilical artery.  23 days after vaccination, at gestational age of 39.1 weeks, the subject's mother delivered by caesarean method a male neonate of an unknown body weight, head circumference, and body length. The appearance, pulse, grimace, activity, and respiration (APGAR) scores were 8 at one minute and 9 at five minutes. APGAR score was not reported for 10 minutes. There was no MCM identified at birth.  The outcome of event single umbilical artery was recovered.   The event of single umbilical artery is considered serious due to criterion of medically significance, per company.  The reporter did not provide causality assessment.  This case is linked to cases 202001953 (corresponding mother's case).  Company comment: The event single umbilical artery was reported in association with Afluria QIV. Vaccine was administered at 36 weeks of gestation. Typically, an umbilical cord has two arteries and one vein. Some babies have just one artery and vein. However, temporal relationship is implausible. Causal role of the suspect vaccine is assessed as not related. Foetal exposure during pregnancy is assessed as unrelated per company's conventions.; Sender's Comments: The event single umbilical artery was reported in association with Afluria QIV. Vaccine was administered at 36 weeks of gestation. Typically, an umbilical cord has two arteries and one vein. Some babies have just one artery and vein. However, temporal relationship is implausible. Causal role of the suspect vaccine is assessed as not related. Foetal exposure during pregnancy is assessed as unrelated per company's conventions.