According to a study in France, executives and professionals are 2.6 cm (1 in) taller, and university students are 2.55 cm (1 in) taller than the national average. As this case shows, data taken from a particular social group may not represent a total population in some countries. A relatively small sample of the population may have been measured, which makes it uncertain whether this sample accurately represents the entire population. The height of persons can vary over a day, due to factors such as a height increase from exercise done directly before measurement (normally inversely correlated), or a height increase since lying down for a significant period (normally inversely correlated). For example, one study revealed a mean decrease of 1.54 centimetres (0.61 in) in the heights of 100 children from getting out of bed in the morning to between 4 and 5 p.m. that same day. Such factors may not have been controlled in some of the studies. Men from Bosnia and Herzegovina, the Netherlands, Croatia, Serbia and Montenegro have the tallest average height. Dinka people are sometimes noted for their height. With the Tutsi of Rwanda, they are believed to be the tallest people in Africa. Roberts and Bainbridge reported the average height of 182.6 cm (5 ft 11.9 in) in a sample of 52 Dinka Agaar and 181.3 cm (5 ft 11.4 in) in 227 Dinka Ruweng measured in 1953–1954. Other studies of comparative historical height data and nutrition place the Dinka as the tallest people in the world.
Surgery is the only definitive treatment. Studies looking at rates of pelvic pain recurrence after surgery have shown that continuous use of COCPs is more effective at reducing the recurrence of pain than cyclic use. Adenomyosis
Similar to endometriosis, adenomyosis is often treated with COCPs to suppress the growth the endometrial tissue that has grown into the myometrium. Unlike endometriosis however, levonorgetrel containing IUDs are more effective at reducing pelvic pain in adenomyosis than COCPs. Menorrhagia
In the average menstrual cycle, a woman typically loses 35 to 40 milliliters of blood. However, up to 20% of women experience much heavier bleeding, or menorrhagia. This excess blood loss can lead to anemia, with symptoms of fatigue and weakness, as well as disruption in their normal life activities. COCPs contain progestin, which causes the lining of the uterus to be thinner, resulting in lighter bleeding episodes for those with heavy menstrual bleeding. Amenorrhea
Although the pill is sometimes prescribed to induce menstruation on a regular schedule for women bothered by irregular menstrual cycles, it actually suppresses the normal menstrual cycle and then mimics a regular 28-day monthly cycle. Women who are experiencing menstrual dysfunction due to female athlete triad are sometimes prescribed oral contraceptives as pills that can create menstrual bleeding cycles. However, the conditions underlying cause is energy deficiency and should be treated by correcting the imbalance between calories eaten and calories burned by exercise. Oral contraceptives should not be used as an initial treatment for female athlete triad.