Latex mattresses do not get harder over time. The materials are not designed to get harder and will last for at least 20 years. Unlike other types of mattresses, latex mattresses do not have a “break-in” period, meaning your body does not have to adjust to a latex mattress as the material is naturally supportive. However, a latex mattress may first cause you some discomfort at first. This is especially true if you have been sleeping on a memory foam mattress for some time.