Sayyiduna Uqbah bin Amir al-Juhani (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "The conditions most deserving to be fulfilled are those by which you make private parts lawful."
Imam al-Shafi'i (may Allah have mercy on him) said: Conditions that are in accordance with the Sunnah may be fulfilled, while it is not right to fulfil conditions that are contrary to the Sunnah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصداق / 14431