Praise be to Allah.
It should be pointed out that a woman’s work may be haraam, if it involves mixing with men or selling or making things that are haraam, or working in a bank, and so on.
If that is the case, then the woman should give up this work and look for a permissible job. Her husband is obliged to spend on her on a reasonable basis, according to what he can afford. See question no. 33710.
If her work is permissible, and she falls sick and going to work is too difficult for her, or will delay her recovery or make her sicker, then the husband must pay attention to that. It is not permissible for him to demand that his wife do something that will cause her harm.
The husband must treat his wife in a kind and reasonable manner. Allaah says (interpretation of the meaning):
“and live with them honourably”
It is not reasonable or honourable to demand that the wife go to work when she is sick.
The Prophet (peace and blessings of Allaah be upon him) enjoined the men of his ummah to treat women well: “(I urge you) to treat women well.” (Narrated by al-Bukhaari, 3331; Muslim, 1468.
What this hadeeth means is: accept this advice and follow it: treat them kindly and live with them honourably.
The husband should not doubt his wife’s sincerity; his life with her should be based on trust and honesty, not suspicion and doubt.
If the husband is not convinced by the medical reports which prove that his wife is sick, and he is not convinced by the signs of sickness that he sees in her, then he will never be convinced by anything. So the wife should try (to convince him) in a gentle manner and treat him in a way that is better; may Allaah guide him to that which is best for his family.
And Allaah knows best.