DEFINITION of 'Substitution Effect'. The idea that as prices rise (or incomes decrease) consumers will replace more expensive items with less costly alternatives.
Dysmenorrhea, also known as dysmenorrhoea, painful periods, or menstrual cramps, is pain during menstruation. It usually begins around the time that menstruation begins. Symptoms typically last less than three days. The pain is usually in the pelvis or lower abdomen.Other symptoms may include back pain, diarrhea, or nausea. In young women painful periods often occur without an underlying problem.t usually begins around the time that menstruation begins. Symptoms typically last less than three days. The pain is usually in the pelvis or lower abdomen. Other symptoms may include back pain, diarrhea, or nausea. In young women painful periods often occur without an underlying problem.
Primary dysmenorrhea is common menstrual cramps that are recurrent (come back) and are not due to other diseases. Pain usually begins 1 or 2 days before, or when menstrual bleeding starts, and is felt in the lower abdomen, back, or thighs.enstrual cramps are caused by contractions (tightening) in the uterus (which is a muscle) by a chemical called prostaglandin. The uterus, where a baby grows, contracts throughout a woman's menstrual cycle. During menstruation, the uterus contracts more strongly.