The purpose of this study is to determine the reasons why multiparous women (women who are pregnant and have been pregnant before) might still be susceptible to rubella.

This study is designed to investigate why multiparous women might still be susceptible to rubella. All pregnant women are checked for rubella immunity, and if they are non-immune, there are standard orders in our hospital to administer the rubella vaccine on the post-partum floor prior to discharge home from the hospital. Despite this, some multiparous women are found to be susceptible (non-immune), and this study will explore the reasons for this.

Inclusion Criteria:

• All rubella susceptible women who delivered during the study period.

All rubella susceptible women who delivered during the study period.