Eleanor was presumably a healthy woman for most of her life; that she survived at least sixteen pregnancies suggests that she was not frail. Shortly after the birth of her last child, however, financial accounts from Edward's household and her own begin to record frequent payments for medicines to the queen's use. The nature of the medicines is not specified, so it is impossible to know what ailments were troubling her until, later in 1287 while she was in Gascony with Edward, a letter to England from a member of the royal entourage states that the queen had a double quartan fever. This fever pattern suggests that she was suffering from a strain of malaria. The disease is not fatal of itself, but leaves its victims weak and vulnerable to opportunistic infections. Among other complications, the liver and spleen become enlarged, brittle, and highly susceptible to injury which may cause death from internal bleeding. There is also a possibility that she had inherited the Castilian royal family's theorised tendency to cardiac problems.