Stefanie Vögele was the defending champion, but chose not to participate.
Elitsa Kostova was the defending champion from the event's previous edition as an ITF Women's Circuit tournament, but lost in the first round of qualifying to Barbora Štefková.
This is the first edition of the tournament.
Angelique Kerber was the two-time defending champion, but lost in the second round to Kristina Mladenovic. As a result of her loss, Serena Williams regained the world no.1 ranking, despite being on a pregnancy leave. The tournament marked the return of Maria Sharapova, after serving a 15-month suspension.
Coco Vandeweghe was the defending champion, but lost in the first round to Carina Witthöft.
Pauline Parmentier was the defending champion, but lost in the semifinals to Tatjana Maria.
Rebecca Šramková was the defending champion, but chose not to participate.
Maryna Zanevska was the defending champion, but chose not to participate.
Markéta Vondroušová was the defending champion, but lost in the second round to Elise Mertens.
Mona Barthel was the defending champion, but lost in the first round to Antonia Lottner.
Markéta Vondroušová was the defending champion, but chose not to participate.
This was the first edition of the tournament.
Mihaela Buzărnescu was the defending champion, but chose not to participate.
Carina Witthöft was the defending champion, but lost in the first round to Vera Lapko.
Georgina García Pérez was the defending champion, but chose to participate at the 2019 Burnie International instead.
Anna Blinkova was the defending champion, but chose not to participate.
Petra Kvitová was the defending champion, but chose not to participate this year.
Richèl Hogenkamp was the defending champion, but retired in the semifinals against Tamara Korpatsch.
Ekaterine Gorgodze was the defending champion, but chose to participate in Warsaw instead.
Iga Świątek was the defending champion, but chose not to participate.
