"Then as far as dama (self-control) is concerned, it is not only meant for other orders of religious society, but is especially meant for the householder. Although he has a wife, a householder should not use his senses for sex life unnecessarily. There are restrictions for the householders even in sex life, which should only be engaged in for the propagation of children. If he does not require children, he should not enjoy sex life with his wife. Modern society enjoys sex life with contraceptive methods or more abominable methods to avoid the responsibility of children. This is not in the transcendental quality, but is demoniac. If anyone, even if he is a householder, wants to make progress in spiritual life, he must control his sex life and should not beget a child without the purpose of serving Kåñëa. If he is able to beget children who will be in Kåñëa consciousness, one can produce hundreds of children, but without this capacity one should not indulge only for sense pleasure."
(Srila A.C. Bhaktivedanta Swami Prabhupada. Bhagavad Gita 16:1-3. purport. The Divine And Demoniac Natures.)