Understanding the blood‐feeding behavior of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is important to the control of this malaria vector. Whereas the mosquito's decision to initiate blood feeding under different physiological states is well‐studied, its decision to terminate a blood meal in the face of a defensive host has received little attention. In light of this, we assayed the response of females when disturbed during a blood meal, in a size‐energy state factorial experiment. We found that a mosquito's decision to abandon its host is dependent not only on its relative blood intake, but also on its size and energy state. In particular, mosquitoes are more likely to terminate feeding with increasing relative blood meal size, with the exception of small, high‐energy ones, on which they tend to continue feeding. Mosquitoes that have engaged in prediuresis also tend to abandon their host more readily than those that have not. We discuss our results with regards to the marginal returns in fitness (via fecundity) of continuing feeding for body size, energy state, and interactions.