Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
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:
1- Removing unwanted hair from the body is an act of fitrah. Referring to this, the Prophet (peace and blessings be upon him) is reported to have said: “The fitrah is five things: circumcision, trimming the mustache, cutting the nails, plucking the armpit hairs and shaving the pubic hairs.” (Al-Bukhari and Muslim)
2- All safe methods to remove unwanted hair from the body are permissible in Islam.
In his response to the question, Dr. Muzammil Siddiqi, former president of the Islamic Society of North America (ISNA), states:
All safe methods to remove unwanted hair from the body are permissible in Islam. In the past, Muslim jurists allowed the use of lime or An-Nawrah or some other depilatory agents; so in a similar fashion modern lotions (if they are safe for the skin) can be considered permissible.
It is a Sunnah to remove the pubic hair and hair under the armpits for the purposes of general hygiene and cleanliness. Hair in such areas is considered unwanted. It is makruh to let them grow for more than forty days.
Allah Almighty knows best.