This is an observational study case initially received on 22-Feb-2019, concerning a 23-year-old, adult pregnant female, body mass index (BMI): 30.3, weight: 83.9 kg and height: 166.37 cm, enrolled in a prospective observational safety study on pregnancy outcomes in women immunized with seasonal cell culture influenza trivalent (TIVc) or quadrivalent (QIVc) vaccine during pregnancy. The subject had no history of any previous pregnancies. Also, the subject had no maternal history with major congenital malformations. The subject had a paternal history with major congenital malformation that included father of baby's cousin had sickle cell disease (as reported). The subject did not use tobacco, alcohol or illicit drugs during pregnancy. The type of pregnancy was singleton. The subject's last menstrual period date was 21-Jun-2018. The subject's current conditions included anemia, obesity with body mass index (BMI) 30 plus and asthma since unknown dates and nausea (start date: 14-Sep-2018 to ongoing). The concomitant medication of the subject included promethazine for nausea. On 14-Sep-2018, the subject underwent Nuchal ultrasound and there was no major congenital malformation noted. On 12-Oct-2018, the pregnant subject was administered Flu Vaccine Cell Subunit QIV NVD (dose: 0.5 ml, batch number: 252226, route of administration, expiry date and anatomical location: not reported) for an unknown indication (explicitly considered as vaccine exposure during pregnancy). On the same day, the subject underwent 2nd trimester screen test and MSAFP (maternal serum alpha-fetoprotein screening)/serum markers test and there was no major congenital malformation noted. On 25-Oct-2018, the subject underwent anatomy ultrasound and there was no major congenital malformation noted. On 28-Dec-2018, at gestational age of 27.1 weeks the subject started Citral natal bloom (dose: 1 tablet daily, route of administration: oral) for OB care and the subject was still taking it. On the same day, the subject was also administered TDAP [diphtheria vaccine toxoid, pertussis vaccine acellular, tetanus vaccine toxoid, dose: 0.5 ml (frequency reported as 1), route of administration: intramuscular, batch number, expiry date and anatomical location: not reported) for an unknown indication. On 28-Dec-2018, 2 months and 16 days after vaccination, the subject experienced gestational diabetes mellitus (GDM). On 31-Jan-2019, at gestational age of 32 weeks, the subject started Diclegis (doxylamine succinate, pyridoxine hydrochloride) at a dosage of 4 tablet daily orally for nausea. On 15-Feb-2019, informed consent was given by the subject. On 18-Feb-2019, at gestational age of 34.6 weeks, 4 months and 6 days after vaccination, the subject experienced pre-eclampsia. On the same day the subject started taking metformin at an unknown dosage orally for gestational diabetes mellitus. On an unknown date after vaccination, the subject's pregnancy complications status was collected and noted as eclampsia. The subject's estimated date of delivery and corrected estimated date of delivery was reported as 28-Mar-2019.; Reporter's Comments: A 23-year-old pregnant subject with concurrent conditions (anemia, obesity with BMI 30 plus and asthma) experienced gestational diabetes mellitus, 2 months 16 days after administration of study vaccine at 16 weeks of gestation (coded to Exposure during pregnancy). The subject also experienced pre-eclampsia, 4 months and 6 days after vaccination and eclampsia was noted on an unspecified date. Considering the clinical course of events (gestational diabetes mellitus, pre-eclampsia and eclampsia) and lack of evidence suggesting any causal role, the underlying pregnancy associated with risk factors (anemia, obesity with BMI 30 plus and asthma) appears as a more possible explanation rather than study vaccine and were assessed as not related to study vaccine. The case is further confounded by co-administered drugs. The decision to administer a vaccine during pregnancy is related to medical decision making by the mother and her physician and is not related to any property of the medication. The event of exposure during pregnancy was assessed as not related considering the intended use of the vaccine. The company assessed this case as serious (medically significant).