The purpose of this Registry is to detect and describe any abnormal pregnancy outcomes, including teratogenicity, in females intentionally or unintentionally exposed to Boostrix during their pregnancies in the US. The Registry requires voluntary, prospective reporting of eligible pregnancies by patients and health care providers (HCPs). Data such as vaccination with Boostrix during pregnancy or within 28 days preceding conception, potential confounding factors (such as exposure to other medications) and information related to the outcome of the pregnancy will be collected prospectively

The Registry was originally initiated on 03 May 2005, as part of a program of enhanced pharmacovigilance. Following new European Union Pharmacovigilance legislation, pregnancy registries are to be considered as post-authorization safety studies (PASS). The ongoing Registry will therefore be converted into a PASS study in Q1 2014.

Exposed pregnancies reported to the Registry before the transition into a PASS (between 03 May 2005 and Q1 2014), from which data were collected and analyzed prospectively, will also be included in the analyses.

Some pregnancy exposures may be reported after pregnancy outcome has been identified (retrospective reports). The Registry will capture retrospective reports, but these reports will not be included in the analyses of prospective reports.

Pregnancy outcome data will be collected using questionnaires within 2 months of the estimated date of delivery (EDD) and approximately 6 months and 12 months after the EDD (for all live births for whom the contact details of their HCP will be available) to ascertain the presence of birth defects not diagnosed before, from Q1 2014 to Q3 2019.

Inclusion Criteria:

A subject will be included in the Registry if all of the following criteria are met:

• Exposure to vaccine occurs during pregnancy or within 28 days preceding conception.
• Subject is a US resident.
• A HCP is identified (name, address and phone number).
• Subject can be identified (by GSK or HCP).

Data from registered subjects will be included in the analyses if the following criterion is met:

• Pregnancy is ongoing and the outcome is unknown.

Exclusion Criteria:

Data from registered subjects will not be included in the analyses if the following criterion is met:

• Outcome of pregnancy is known at the time of initial report. Types of known outcomes include prenatal testing reports in which the results are abnormal or outside the reference range, indicating possible abnormality in the fetus. Typically, pregnancies > 16 weeks gestation will have undergone prenatal testing that can identify whether a child has congenital abnormalities.

Eligible pregnancies reported by patients and HCPs

Data collected between 03 May 2005 to 02 August 2019: For each subject from date of registration until the pregnancy outcome documentation date (Exposure_Prospective group) or at pregnancy outcome documentation date (Exposure_Retrospective group)

Classification of events as SAE or other AE were unidentified. Pregnancy case reports were analyzed by case in scope of the Registry. Those cases may have had AEs co-reported. The systematic analysis of these AEs was not among the objectives of the study.