Courtney Fritz Pandolfi, 40, appeared before a judge via video.
Prosecutors say she jumped a curb on Aug. 11, hitting and killing 23-year-old Yesenia Aguilar, who was eight months pregnant.
Aguilar was out on a walk with her husband, James Alvarez, who was not hurt.
Their baby girl Adalyn Rose was delivered by emergency cesarean section and survived.
Pandolfi was previously convicted of DUI three times before last month's deadly crash.
A GoFundMe page has been set up for Adalyn Rose.
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