Historically, paternity of children born out of adultery has been seen as a major issue. Modern advances such as reliable contraception and paternity testing have changed the situation (in Western countries). Most countries nevertheless have a legal presumption that a woman's husband is the father of her children who were born during that marriage. Although this is often merely a rebuttable presumption, many jurisdictions have laws which restrict the possibility of legal rebuttal (for instance by creating a legal time limit during which paternity may be challengedsuch as a certain number of years from the birth of the child). Establishing correct paternity may have major legal implications, for instance in regard to inheritance.