In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear questioner! Thank you for your question and the confidence you place in our service and we pray to Allah to enable us render this service purely for His Sake.
What you have heard is incorrect and has no basis in Islam. A Muslim is permitted to have intercourse more than once with his wife without having to performghuslbetween them. It is only recommended that the person has eitherwudu’(ablution) orghusl(complete bath), which is better.
In this context,Sheikh Muhammad Saleh Al-Munajjid, a Saudi Muslim scholar and lecturer, issues the following fatwa:
“If a man has intercourse with his wife and wants to come back to her a second time, he should dowudu’, because the Prophet (peace and blessings be upon him) said:“If any one of you has intercourse with his wife then wants to repeat it, let him dowudu’between the two (actions), for it is more energizing for the second time.”(Narrated by Muslim). This is recommended, not obligatory; if he is able to doghuslbetween the two actions, this is better, because of the hadith of Abu Rafi` who said that the Prophet (peace and blessings be upon him) went around his wives one day (visited them in their houses and had intercourse with each) and didghuslin this one’s house and in this one’s house. He (Abu Rafi`) said: I said to him, “Messenger of Allah, why do you not do oneghusl?” He said,“This is cleaner and better and purer.”(Narrated by Abu Dawud and An-Nasa’i)”
Excerpted, with slight modifications, from: www.islam-qa.com