The purpose of this post-marketing commitment safety study is to evaluate the real-world safety of HZ/su vaccine during pregnancy in immunodeficient or immunosuppressed adult pregnant women between 18 and 49 years of age in the United States. The primary outcome of interest is major congenital malformations (MCMs).

Inclusion Criteria:

• Participant who is pregnant with a pregnancy start date between 01 July 2021 and 30 June 2026. Live births are to be followed for 1 year.
• Participant is a female aged 18-49 years on the pregnancy start date.
• Participant meets study definition of systemic lupus erythematosus (SLE), multiple sclerosis (MS), rheumatoid arthritis (RA), inflammatory bowel disease (IBD), psoriasis (PsO)/psoriatic arthritis (PsA), solid organ transplant (SOT), stem cell transplant (SCT), hematologic malignancies (HM), solid tumors (ST), or human immunodeficiency virus (HIV). Codes for immunocompromised conditions will be identified in the health plan claims of the Distributed Research Network (DRN) during the period 273 days prior to the pregnancy start date through the first trimester (98 days after the pregnancy start date). Diagnoses recorded through the first trimester will be included to account for women who may not have frequent visits prior to pregnancy and may have a more complete assessment of medical conditions during the first prenatal care visit.
• Participant has at least 273 days of continuous health plan enrollment with medical and drug benefits prior to the start of pregnancy through the delivery date, with gaps of up to 45 days in coverage being permitted. The 273-day pre-pregnancy period through the first trimester (a period of 98 days after the pregnancy start date) was chosen to allow identification of potential confounders of interest. In Sentinel projects, gaps of 45 days or less in health plan enrolment are typically considered administrative gaps (and not lapses in health plan coverage) and ignored.

Exclusion Criteria:

• Participant was exposed to a medication(s) that presents a known increased risk for fetal malformations.
• Participant delivered an infant identified as having a chromosomal or genetic anomaly.
• Ectopic pregnancies, molar pregnancies or induced abortions.
• Multigestation (e.g., twin) pregnancies.

Adult pregnant women, 18-49 years of age, diagnosed with an immunocompromised condition who were members of any of the 4 participating Sentinel Research Partners.