Short answer
Condoms may be considered as a temporary method of pregnancy spacing within marriage, subject to the applicable Islamic scholarly opinion and medical suitability.
Islamic Guidance
What Islam teaches
Temporary pregnancy prevention has been discussed by classical Islamic scholars through the subject of 'azl. Scholars have differed over details, so couples should follow a reliable scholarly opinion appropriate to their circumstances.
Practical Guidance
What you can consider
Discuss pregnancy spacing jointly and obtain medical advice about the safest contraceptive option for the couple.
Sources
Sahih al-Bukhari, Book of Marriage; Sahih Muslim, Book of Marriage.