The number of dead in Bangladesh in 1971 was almost certainly well into seven figures. It was one of the worst genocides of the World War II era, outstripping Rwanda (800,000 killed) and probably surpassing even Indonesia (1 million to 1.5 million killed in 1965-66). As R.J. Rummel writes,
The human death toll over only 267 days was incredible. Just to give for five out of the eighteen districts some incomplete statistics published in Bangladesh newspapers or by an Inquiry Committee, the Pakistani army killed 100,000 Bengalis in Dacca, 150,000 in Khulna, 75,000 in Jessore, 95,000 in Comilla, and 100,000 in Chittagong. For eighteen districts the total is 1,247,000 killed. This was an incomplete toll, and to this day no one really knows the final toll. Some estimates of the democide [Rummel's "death by government"] are much lower -- one is of 300,000 dead -- but most range from 1 million to 3 million. ... The Pakistani army and allied paramilitary groups killed about one out of every sixty-one people in Pakistan overall; one out of every twenty-five Bengalis, Hindus, and others in East Pakistan. If the rate of killing for all of Pakistan is annualized over the years the Yahya martial law regime was in power (March 1969 to December 1971), then this one regime was more lethal than that of the Soviet Union, China under the communists, or Japan under the military (even through World War II). (Rummel, Death By Government, p. 331.)
The proportion of men versus women murdered is impossible to ascertain, but a speculation might be attempted. If we take the highest estimates for both women raped and Bengalis killed (400,000 and 3 million, respectively); if we accept that half as many women were killed as were raped; and if we double that number for murdered children of both sexes (total: 600,000), we are still left with a death-toll that is 80 percent adult male (2.4 million out of 3 million). Any such disproportion, which is almost certainly on the low side, would qualify Bangladesh as one of the worst gendercides against men in the last half-millennium.
Gendercide Watch: Genocide in Bangladesh, 1971
Nevertheless, for me the most hatred part of the genocide is the killing of the brightest sons of the nation in 14th December, 1971 to make the nation brainless!! It definitely pushed the nation few decades back!!