LABOR NOT PROGRESSING; GESTATIONAL DIABETES; MATERNAL EXPOSURE DURING PREGNANCY; CHILLS; This solicited pregnancy report received from a health care professional concerned a 30 year old female. The patient was enrolled in a non-company sponsored study. The patient's weight was 93.42 kilograms, and height was not reported. The patient's concurrent conditions included anxiety, asthma, polycystic ovary, non alcohol user, polycystic ovarian syndrome, tobacco user, e-cigarette smoker, and recreational drug use. Other pre-existing medical conditions included no relevant obstetrical history. The patient initiated treatment with covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: Unknown) dose was not reported, 1 total administered on 13-MAR-2021 for covid-19 immunisation. The batch number was not reported. Per procedure, no follow-up will be requested for this case. Concomitant medications included ascorbic acid/betacarotene/calcium sulfate/colecalciferol/cyanocobalamin/ferrous fumarate/folic acid/nicotinamide/pyridoxine hydrochloride/retinol acetate/riboflavin/thiamine mononitrate/tocopheryl acetate/zinc oxide for drug used for unknown indication, ferrous sulfate for drug used for unknown indication, oxymetazoline hydrochloride for drug used for unknown indication, and loratadine. The first day of the last menstrual period (LMP) was calculated to be 16-Nov-2020. The estimated delivery date (EDD) was reported to be 23-Aug-2021. Type of pregnancy was reported as singleton. On 13-Mar-2021, at gestational age 16 weeks and five days, patient experienced chills. On 02-Jun-2021, patient developed gestational diabetes. On 17-Aug-2021, at gestational age 39 weeks and one day, patient delivered a live female, full-term neonate by caesarean method of delivery (C-section). Primary reason for C-section was reported as labor did not progressed. Patient spent five days in the hospital for delivery. The neonate's birth weight was 8 pounds and 6 ounces, body length 53 cm. Laboratory data (dates unspecified) included: Body mass index (not provided) 35.353 kg/m2, increased. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from gestational diabetes on 16-AUG-2021, and chills on 15-MAR-2021, and the outcome of maternal exposure during pregnancy and labor not progressing was not reported. The reporter considered the causality between covid-19 vaccine ad26.cov2.s, and gestational diabetes as not related. The reporter did not provide a causality assessment between covid-19 vaccine ad26.cov2.s, and labor not progressing, maternal exposure during pregnancy, and chills. Company causality between covid-19 vaccine ad26.cov2.s, and labor not progressing, and gestational diabetes, and maternal exposure during pregnancy was not related, and between covid-19 vaccine ad26.cov2.s, and chills was related.  This report was serious (Hospitalization Caused / Prolonged, and Other Medically Important Condition).  This case was reassessed as serious based on additional information received from other health professional on 04-NOV-2021. The following information was updated and incorporated into the case: Patient's race captured, disease tab (non alcohol user, polysystic ovarian syndrome, tobacco user, E-cigarette smoker, recreational drug use) added, pregnancy tab updated, event gestational diabetes and labor not progressing added, outcome of event chills updated as resolved, lab data added, concomitant drug claritin added, narrative updated.; Sender's Comments: V1: Additional information in this version updates:  Patient's race captured, disease tab (non alcohol user, polycystic ovarian syndrome, tobacco user, E-cigarette smoker, recreational drug use) added, pregnancy tab updated, event gestational diabetes and labor not progressing added, outcome of event chills updated as resolved, lab data added, concomitant drug claritin added, narrative updated, Case reassessed as serious,  20210664638-COVID-19 VACCINE AD26.COV2.S-Gestational diabetes, Labor not progressing. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: MEDICAL HISTORY 20210664638-COVID-19 VACCINE AD26.COV2.S-Maternal exposure during pregnancy. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS 20210664638-COVID-19 VACCINE AD26.COV2.S-Chills This event(s) is labeled per RSI and is therefore considered potentially related.