Health encyclopaedia - Alphabetical Topic List健康百科全书-按字母顺序排列的主题清单

| A | | 1 | | B | | b | | C | | 人才招聘 | | D | | | | E | | 电子 | | F | | f | | G | | 克 | | H | | h | | I | | 我 | | J | | j | | K | | k | | L | | 升 | | M | | 米 |
| N | | n | | O | | o | | P | | p | | Q | |常见问题 | | R | | 研究 | | S | | | | T | | 吨 | | U | | u | | V | | v | | W | | 瓦特 | | X | | x | | Y | | y |

Why is it necessary?为什么要呢？ of IVF对试管婴儿

Infertility in one third of cases can be attributed to factors affecting women, such as problems connected to egg release, blockages in the fallopian tubes, or structural defects (congenital abnormalities) of the uterus.  Another third of cases involve factors affecting men, which may include a low sperm count (oligospermia), poor sperm motility and/or lifespan, or azoospermia where no sperm cells are produced.  The remaining third of infertility cases can be attributed to fertility issues in both partners, or to reasons unknown.不孕症的三分之一的案件可以归因于妇女的影响因素，如问题，连接到鸡蛋释放，堵塞在输卵管，或结构缺陷（先天性畸形）的子宫，另外三分之一的案件涉及的影响因素的男子，这可能包括低精子计数（少） ，穷人的精虫和/或寿命，或无精子症如果没有精子细胞的产生。剩下的三分之一不孕症的案件可以归因于生育率的问题，在这两个合作伙伴，或原因不明。