Chelsea were unable to add to their lead in the second half despite dominating possession, and West Ham’s resilience paid off when Katerina Svitkova pounced on a loose ball in the box to level the scores with just five minutes remaining.
The draw leaves Chelsea six points adrift of leaders Arsenal, who have a game in hand, while West Ham move up to seventh in the Women’s Super League table.
Next up for Chelsea is a crucial Champions League quarter-final second leg against Wolfsburg on Wednesday, with the tie finely poised at 1-1 after the first leg in Germany.