Vaccine exposure via breast milk; Vaccine exposure during pregnancy; This spontaneous prospective pregnancy case was reported by a consumer and describes the occurrence of MATERNAL EXPOSURE DURING PREGNANCY (Vaccine exposure during pregnancy) and EXPOSURE VIA BREAST MILK (Vaccine exposure via breast milk) in a 31-year-old female patient (gravida 1) who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 030L20A and 014M20A) for COVID-19 vaccination.     The patient's past medical history included Sinus tachycardia in 2009 and Alcohol use. Concurrent medical conditions included Hypothyroidism since 2011, Sulfonamide allergy and Gluten sensitivity. Concomitant products included FAMOTIDINE (PEPCID AC) for GERD, ERGOCALCIFEROL (DRISDOL) for Vitamin D deficiency.   On 30-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 27-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. The patient's last menstrual period was on 01-Aug-2020 and the estimated date of delivery was 02-May-2021. On 30-Jan-2021, the patient experienced MATERNAL EXPOSURE DURING PREGNANCY (Vaccine exposure during pregnancy). On an unknown date, the patient experienced EXPOSURE VIA BREAST MILK (Vaccine exposure via breast milk). The patient received mRNA-1273 (Moderna COVID-19 Vaccine) beginning around the  twenty-sixth week of the pregnancy. The vaginal delivery occurred on 27-Apr-2021, which was reported as Normal Pregnancy Outcome. For neonate 1, with an APGAR score of 9 and 10 at (1, 5 minutes). The outcome was reported as Delivered NOS. Infant   was born at exactly 10th percentile. Infant was Breastfeeding male  and   Weight (kg): 13.42 , Length (cm): 48.26. On 30-Jan-2021, MATERNAL EXPOSURE DURING PREGNANCY (Vaccine exposure during pregnancy) had resolved. At the time of the report, EXPOSURE VIA BREAST MILK (Vaccine exposure via breast milk) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 08-Feb-2021, Ultrasound scan: normal (normal) normal. On 08-Mar-2021, Ultrasound foetal: normal (normal) normal. On 30-Mar-2021, Ultrasound foetal: normal (normal) normal. On 20-Apr-2021, Ultrasound foetal: normal (normal) normal.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Treatment information was not provided. Patient's Pre-pregnancy Weight was 155 pounds. Patient's concomitant  drug changed from cardizem to metoprolol for pregnancy and  concomitant  drug  synthroid dosage increased from 150mcg to 175mcg during pregnancy. Concomitant product included prenatal vitamin with DHA for an unknown indication. Patient had  positive pregnancy test on 26-Aug-2020 Patient was diagnosed with IUGR at 32 weeks based upon AC in 6th percentile possibly related to patient taking beta blocker while pregnant.   Most recent FOLLOW-UP information incorporated above includes: On 11-Aug-2021: In follow-up information secondary reporter detail , patient demographics  (i.e.: Ethnic Group ,Date of LMP ) , pregnancy outcome   (i.e.: Delivery Date ,Delivery Type ,Birth Type, Fetal Outcome , fetus/infant details, APGAR Score,  Delivery Notes), Other Relevant History (i.e.: hypothyroidism was updated as  Historical Condition to current condition), Lab data , Concomitant product  details, event (i.e.: Vaccine exposure via breast milk) and I Narrative Supplement   were updated  .