婴儿性别的选择,在理论上有两种方法,一种是在妊娠前性别的预先选择,即仅让活的带X 染色体或Y 染色体的精子接近卵子。另一种方法是选择性中止妊娠。(一)性别的预先选择不可靠:有些人认为碱性液灌洗法和刺激性欲亢进通过使携带Y 染色体的精子更快地游动而首先达到卵子,有利于妊娠男孩。性交时间选择,在排卵期有利妊娠女孩,但仅有65%的可靠性。另一预先选择的可能性是用经人工处理过的精液进行人工受精。曾根据重量把带X 和Y 染色体的精子(带X 染色体的精子部分较重)或在精子头大小,表面电荷或游泳能力基础上作了两种精子分离的尝试。看起来,这些方法大多数效率低。虽然在一次标准调查中,白蛋白梯度可增加带Y 染色体精子的比例达75%,不幸的是在同时精子总计数急剧下降,但已 There are theoretically two ways in which the sex of the baby can be chosen. One is pre-pregnancy gender pre-selection, in which only live X-chromosome or Y-chromosome-bearing sperm are brought close to the egg. Another option is to terminate the pregnancy selectively. (A) Sexual pre-selection is unreliable: Some people think that alkaline fluid lavage and irritant hypersensitivity benefit the gestation boy by first reaching the egg by moving the Y-chromosome bearing sperm faster. Sexual intercourse timing, which favors pregnant women during ovulation, is only 65% ​​reliable. Another possibility of a prior selection is artificial insemination with a hand-processed semen. Two attempts at sperm segregation based on the weight of spermatozoa with X and Y chromosomes (heavier sperm with X chromosomes) or on sperm head size, surface charge, or swimming ability have been made. It seems that most of these methods are inefficient. Although in a standard survey albumin gradients increased the percentage of sperm with Y chromosomes by up to 75%, unfortunately the total number of sperms declined dramatically at the same time