pregnant patient received teh first dose of Moderna vaccine; sore arm; This spontaneous prospective pregnancy case was reported by a consumer (subsequently medically confirmed) and describes the occurrence of MATERNAL EXPOSURE DURING PREGNANCY (pregnant patient received teh first dose of Moderna vaccine) and VACCINATION SITE PAIN (sore arm) in a 30-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 010A21A) for COVID-19 vaccination.     The patient's past medical history included Alcohol use (2 drinks/month) from 25-Feb-2006 to 06-Sep-2020 and Caesarean section (Cephalopelvic disproportion -significant blood loss (Emergency C-section)) on 19-Sep-2018. Previously administered products included for an unreported indication: TDAP (Upper left Arm) on 19-Mar-2021. Concomitant products included CETIRIZINE HYDROCHLORIDE (ZYRTEC [CETIRIZINE HYDROCHLORIDE]) from 04-Jan-2021 to an unknown date and PRONASE from 04-Jan-2021 to an unknown date for Allergy, PROMETHAZINE from 10-May-2020 to 11-May-2020 for Nausea, MINERALS NOS, VITAMINS NOS (PRENATAL PLUS) from 08-Jan-2020 to an unknown date for Pregnancy.    On 26-Feb-2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. The patient's last menstrual period was on 09-Aug-2020 and the estimated date of delivery was 16-May-2021. On 22-Jan-2021, the patient experienced MATERNAL EXPOSURE DURING PREGNANCY (pregnant patient received teh first dose of Moderna vaccine) and VACCINATION SITE PAIN (sore arm). The patient received mRNA-1273 (Moderna COVID-19 Vaccine) beginning around the  twenty-eighth week of the pregnancy. The cesarean delivery occurred on 12-May-2021, which was reported as Full-term. For neonate 1, the birth weight was 3100 grams (6lbs 13oz) with an APGAR score of 9 and 9 at (1, 5 minutes). The outcome was reported as Term Birth w/o Complications. thrombocytopenia  Blood transfusion after delivery Male Fetus length-49cm. On 22-Jan-2021, MATERNAL EXPOSURE DURING PREGNANCY (pregnant patient received teh first dose of Moderna vaccine) had resolved. On 23-Jan-2021, VACCINATION SITE PAIN (sore arm) had resolved. Not Provided    DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 11-May-2020, Prenatal screening test: low risk (Inconclusive) low risk. On 06-Sep-2020, Pregnancy test: positive (Positive) positive. On 05-Nov-2020, Prenatal screening test: negative (Negative) Nothing abnormal, everything was negative. On 23-Dec-2020, Ultrasound abdomen: baby was little bit small (Inconclusive) Baby was a little bit small and normal (normal) normal. On 02-Feb-2021, Ultrasound abdomen: normal (normal) Everything was normal and normal (normal) normal. On 21-Apr-2021, Streptococcus test: negative (Negative) Negative. On 03-May-2021, Blood glucose: 91 (normal) normal. On 18-Sep-2021, Sexually transmitted disease test: negative (Negative) Negative.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Treatment information was not provided. The Estimated date of conception was 15Aug2020   This case was linked to MOD-2021-032146 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 07-May-2021: followup received on 07-may 2021 had included second dosage information and concomitant drugs and second dosage events and Completed Pregnancy Reporting Form after 1st dosage On 23-Jun-2021: Follow-up received on 23-Jun-2021 and does not contain any new information