Thompson, who also won the 200m at the Rio Games last year, is the favourite going into the race as compatriot and three-time world champion Shelly-Ann Fraser-Pryce misses out while she prepares for the birth of her first child.
The 25-year-old Thompson will be challenged by Dafne Schippers of the Netherlands and Tori Bowie of the U.S., who claimed the silver and bronze medals in the same event in Beijing two years ago.
The women's heptathlon also reaches its climax on Sunday in the London Stadium. Germany's Carolin Schafer leads the standings, with Olympic champion Nafi Thiam of Belgium in second with three events remaining.
The first medals of the day come in the marathon, with the men's event beginning at 10:55 local time, with Daniel Wanjiru of Kenya looking to secure a London double, having won the city marathon in April. The women's event begins at 14:00. Both races start and finish at Tower Bridge.
There are also gold medals to be won in the women's pole vault and the men's shot put.
(Reporting by Christian Radnedge; Editing by Neil Robinson)
