I can afford Hajj for myself and my wife but she cannot travel because of pregnancy. Should I travel alone? Should I wait until she delivers, knowing that she will not be able to perform Hajj without me as she does not have a Mahram other than me, and she will have to wait for five years, for Hajj is not permitted except every five years.

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.

The preponderant opinion of scholars is that Hajj is obligatory on an immediate basis. Whenever a person has the ability to perform Hajj, he should perform Hajj in the same year.

Therefore, you should perform Hajj this year. Do not delay your Hajj for you do not know what might happen to you in the future.

Concerning your wife, if she cannot go with you at the time of Hajj due to your fear for her pregnancy, then you may both perform Hajj next year. If you cannot perform Hajj next year because you are not allowed to accompany her and she does not have another Mahram who is allowed to perform Hajj, then Hajj is not obligatory upon your wife because she cannot find a way thereto. Allah Almighty says (what means): {And [due] to Allah from the people is a pilgrimage to the House—for whoever is able to find thereto a way...} [Quran 3: 97]

Allah Knows best.