Yeast; [Headache]/nausea; Vaccine exposure during pregnancy; Headache/[nausea]; This is an observational study case, initially received from other health professional on 16-Aug-2019, concerning a 26-year-old, pregnant, female subject of body weight: 183 lbs, height: 64.8 inches and body mass index (BMI): 30.6, enrolled in a prospective observational safety study.  The subject's obstetrical history noted that the subject had 3 previous pregnancies which included 1 full term live birth, 1 spontaneous abortion and 1 elective abortion. No birth defects were reported. Also, the subject had no maternal or paternal history with major congenital malformations. The subject did not have a prior history of use of tobacco, alcohol or illicit drugs during pregnancy. The subject's current medical history included: pregnancy induced hypertension, anxiety, cervico occipital neuralgia, genital herpes simplex and obesity.  The subject's concomitant medications included: Citranatal (ascorbic acid, calcium citrate, colecalciferol, cupric oxide, docosahexaenoic acid, docusate sodium, eicosapentaenoic acid, folic acid, iron, nicotinamide, potassium iodide, pyridoxine hydrochloride, riboflavin, thiamine, tocopheryl acetate, zinc oxide) as vitamin, nifedipine for hypertension, and buspirone for anxiety.  The subject's last menstrual period (LMP) date was 19-Nov-2018, estimated delivery date (EDD) and corrected estimated date of delivery (CEDD) were both 26-Aug-2019. The type of pregnancy was singleton.  On 28-Jan-2019, at gestation age of 10 weeks, the subject was administered Flucelvax QIVc [influenza vaccine, subunit influenza virus vaccine polyvalent, at a dose of 0.5 ml, batch number: 252678, expiration date, route of administration and anatomical location: not reported] (explicitly coded as vaccine exposure during pregnancy) for influenza immunisation.  On 14-Feb-2019, first trimester screen and nuchal translucency was performed and no major congenital malformation was noted.  On 13-Mar-2019, second (2nd) trimester screen and maternal serum alpha-fetoprotein (MSAFP) / serum markers was performed and no major congenital malformation was noted.  On 01-Apr-2019, anatomy ultrasound was performed and no major congenital malformation was noted.  On unspecified dates, the subject developed headache/nausea and yeast. The subject started therapy with Diclegis (doxylamine succinate, pyridoxine hydrochloride) at a dose 2 tablets, administered via oral route every day, as a corrective treatment for morning sickness, ondansetron at a dose 1 tablet, administered via oral route every day, as a corrective treatment for headache/nausea and terconazole cream, administered via vaginal route every day, as a corrective treatment for yeast.  At the time of this report, the outcome of the events was not reported.  Company comment: The patient developed fungal infection, headache and morning sickness on an unspecified date, after vaccination with Flu Vaccine Cell Subunit QIV NVD, administered at 10 weeks of gestation. Chronology needs more clarification. Although causality was confounded by medical history of pregnancy, hypertension, anxiety, occipital neuralgia, genital herpes simplex and treatment with concomitant medications, causal role of the suspect vaccine cannot be totally excluded and was assessed as related for the events of fungal infection, headache and morning sickness. The event of vaccine exposure during pregnancy was assessed as not related considering the intended use of the vaccine.; Reporter's Comments: The patient developed fungal infection, headache and morning sickness on an unspecified date, after vaccination with Flu Vaccine Cell Subunit QIV NVD, administered at 10 weeks of gestation. Chronology needs more clarification. Although causality was confounded by medical history of pregnancy, hypertension, anxiety, occipital neuralgia, genital herpes simplex and treatment with concomitant medications, causal role of the suspect vaccine cannot be totally excluded and was assessed as related for the events of fungal infection, headache and morning sickness. The event of vaccine exposure during pregnancy was assessed as not related considering the intended use of the vaccine.