Observational Study to Evaluate the Safety of CYD Tetravalent Dengue Vaccine (CYD-TDV) in Pregnant Women and Their Offsprings Inadvertently Exposed During Pregnancy

Primary Objective: To evaluate the safety of CYD-TDV in pregnant women and their offsprings inadvertently exposed during pregnancy or up to 30 days preceding their last menstrual period (LMP) with regards to maternal, pregnancy, birth, neonatal and infant outcomes. Specifically, the frequency/rates of these outcomes will be: (i) described, and (ii) compared with population-level background incidence rates prior to the introduction of CYD-TDV immunization (i.e., external unvaccinated comparator). Secondary Objective: To describe: * the characteristics of women exposed to CYD-TDV during pregnancy or up to 30 days before the LMP * the characteristics of CYD-TDV pregnancy exposure with regards to number of doses, dose intervals, and trimester of exposure.

This is a non -interventional (observational) post authorization safety study (PASS): no vaccine will be administered as part of the study. This pregnancy registry study is a combination of a retrospective (outcomes occurred before the start of participant enrollment) and prospective (outcomes occurred after the start of participant enrollment) cohort study using active identification and enrollment of pregnant women and their offsprings inadvertently exposed to CYD-TDV during pregnancy or up to 30 days preceding the LMP. The study period will be from July 2016 (first availability of Paraná's Immunization Registry) to July 2022 (end of last follow-up interview for offsprings), and the participant enrollment period will last approximately 1 year. Study duration per participant will vary depending on: 1) the stage of pregnancy at the time the participant will be enrolled; 2) whether the participant will be included retrospectively or prospectively. The maximum duration will be 22.5 months (up to 9 months of pregnancy + 42 days post-delivery \[puerperium period\] + 12 months post-birth).