First, a true Muslim has to believe that Allah is all-Sustainer and it is he who gives provision to all His creatures.
Having a lot of children is something that is encouraged in Islam and the Prophet (blessings and peace be upon him) urged Muslims to do that. Abu Dawud narrated that Ma’qil ibn Yasar said: A man came to the Messenger of Allah (peace and blessings be upon him) and said: “O Messenger of Allah, I have found a woman who is from a good family and is beautiful, but she does not bear children; should I marry her?” He told him not to. Then he came to him a second time and said something similar and he told him not to marry her. Then he came to him a third time and said something similar and he (peace and blessings be upon him) said: “Marry the one who is loving and fertile, for I will be proud of your great numbers.”
Hence, the couple should be keen to have a lot of children and be happy about that and show gratitude for the blessing that Allah has bestowed upon them.
Second, it is permissible to delay having children for a certain period of time if that serves an interest, such as if the woman is weak or sick. But it is not permissible to do that for fear of poverty or for fear of raising the children, because that implies thinking negatively of Allah, may He be exalted.
In it’s statement concerning this issue, the Islamic Fiqh Council affirmed unanimously that it is not permissible to limit the number of children in general and it is not permissible to prevent pregnancy if the reason for doing such is fear of poverty, because Allah is the Provider and Owner of great power, and there is no living creature on earth but its provision is due from Allah, or if that is for other reasons that are not acceptable according to sharia.
As for using contraception or delaying pregnancy in individual cases where real and certain harm will result from it, there is nothing in sharia to prevent such a person form doing that. The same applies if pregnancy is delayed for other legitimate sharia or health reasons confirmed by a trustworthy Muslim doctor. Contraception becomes a must in a case where it is proven that the mother’s life will be at risk or there is the fear that she may die, according to the opinion of a trustworthy Muslim doctor.
When a lady is pregnant and her health will not be dangerously affected by such pregnancy, she and her husband should thank Allah for His gift and put their trust in Him seeking His help and grace to enable them raise their children according to the true teaching of His religion. They should have this good intention of bringing up t their children to be good Muslims who care for their religion and their Ummah.
Therefore, a lady whose husband does not want more children should approach him gently and remind him of Allah and His favor and how firmly he should put his trust in Him.
May Allah grant you success and set your affairs aright.