男人不会理解大姨妈有多疼女人不会了解蛋疼会有多疼
[nán rén bù huì lĭ jiĕ dà yí mā yŏu duō téng nǚ rén bù huì le jiĕ dàn téng huì yŏu duō téng]
'Men will never understand how painful a period is; women won't understand how painful testicular pain can be.' A humorous expression highlighting the gender-based experience of physical pain, reflecting the idea that men and women suffer differently.