To correctly understand this often-misunderstood subject, we must look to the One who created the human body. While God does say, "Be fruitful and multiply" (Genesis 1:28), and "Behold, children are a heritage from the LORD" (Psalm 127:3), He also holds parents responsible for providing for their children (I Timothy 5:8; II Corinthians 12:14; Proverbs 13:22). A couple should not have more children than they can care for and support in every way in deep concern and love.
This, of course, means that each couple will likely need to consider the use of some form of birth control. A further consideration is the welfare of the mother. A woman's health can be severely affected by having too many children too closely together. Husbands ought to have a proper concern for the health of their wives (Ephesians 5:25).
The Bible does not describe the various modern methods of birth control. This is a physical matter, and God expects us to investigate and evaluate the information available and come to a responsible conclusion. Each couple should take into account their particular circumstances when evaluating which method is best for them.
It should be noted that some methods are less reliable, a few may be permanent, and others may have undesirable side effects. In addition, a small number of methods—the so-called "morning after" drugs—induce an early yet post-fertilization abortion. These, of course, should not be considered, as they violate the sixth commandment (Exodus 20:13).
Many books on the subject of birth control methods are available at local libraries or bookstores. Such books will contain information on each type of contraception available today and describe the advantages and disadvantages. One can also check out the many health resources on the Internet for such information.