Answer

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.

In this fatwa:

Married couples can bath together. Prophet Muhammad (peace be upon him) used to take a bath with his wife. Also, married couples can have sex in a bathroom.

In responding to your question about having sex in a bathroom, Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author, states: 

It is permissible for a man to have intercourse with his wife without a cover. It is also permissible for couples to have sex in a bathroom. But that means that he will be going against the Sunnah by not mentioning Allah beforehand.

Perhaps you know that the Sunnah, when a man wants to have intercourse with his wife, is to say, 

‘Bismillah, Allahumma jannibna ash-Shaytana wa jannib ash-Shaytana ma razaqtana (In the Name of Allah, O Allah, keep Satan away from us and from that with which You may bless us).” (Al-Bukhari and Muslim)

Almighty Allah knows best.

Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.

Source: www.islamqa.info/en