1. There  are many different causes of infertility. Some are genetic. Others involve  physical problems or injuries. Still others are environmental, like  pesticides and other chemicals.

2. The  best-known current treatment for infertility is a process called in vitro  fertilization. Treatments can also involve the use of fertility drugs to  increase the production of eggs.

3. But  many criticize in vitro fertilization as unnatural, and others question  whether women past menopause, who are in their 50s and 60s, should be helped  to give birth.

4. He says  that without the once-experimental procedure, he and his brother would not  have been born, and that today he strongly supports stem cell research and  other cutting-edge medical technologies.

5. But  over the years, the procedure has become more routine. It is a wonderful  option for many infertile women if they are willing to bear the emotional,  physical and financial costs.

不育有许多不同的原因。有些是遗传的，另一些是身体问题或受伤，还有一些是环境的，如杀虫剂和其他化学品。

目前最熟知的不育治疗是一种称为体外受精的过程。治疗也可以涉及使用生育药物来增加产卵。

但许多人批评体外受精是不自然的，另些人质疑是否应该帮助过了更年期的50岁和60岁的妇女生育。

他说，没有曾经的实验手术，他和他的弟弟不会出生。他还说今天他坚决支持干细胞研究和其他尖端医疗技术。

但经过多年，该手术已成为常规。如果许多不育女性愿意在情感、身体和经济上承受，这是一项不错的选择。