Daughter
In the United States, the birth rate is 105 sons to 100 daughters which has been the natural birth rate since the 18th century. About 80 percent of prospective adoptive parents from the US will choose a girl over a boy. In fertility clinics that enable sex preferences, daughters are usually preferred over sons. In the traditions of various Abrahamic religions, Luluwa is regarded as the first daughter to have ever existed.
Sterilization (medicine)
Because of the emphasis placed on childbearing as the most important role of women, not having children was traditionally seen as a deficiency or due to fertility problems. However, access to contraception and abortion, new economic and educational opportunities, and changing ideas about motherhood have led to new reproductive experiences for women in the United States, particularly for women who choose to be childless. Scholars define "voluntarily childless" women as "women of childbearing age who are fertile and state that they do not intend to have children, women of childbearing age who have chosen sterilization, or women past childbearing age who were fertile but chose not to have children." 
In industrialized countries such as the United Kingdom, those of Western Europe, and the United States, the fertility rate has declined below or near the population replacement rate of two children per woman. Women are having children at a later age, and most notably, an increasing number of women are choosing not to bear children at all. According to the U.S. Census Bureau's American Community Survey, 46% of women aged 15 to 44 were childless in June 2008 compared to 35% of childless women in 1976. The personal freedoms of a childless lifestyle and the ability to focus on other relationships were common motivations underlying the decision to be voluntarily childless. Such personal freedoms included increased autonomy and improved financial positions. The couple could engage in more spontaneous activities because they didn't need a babysitter or to consult with someone else. Women had more time to devote to their careers and hobbies. Regarding other relationships, some women chose to forgo children because they wanted to maintain the "type of intimacy that they found fulfilling" with their partners. Although voluntary childlessness was a joint decision for many couples, "studies have found that women were more often the primary decision makers. There is also some evidence that when one partner (either male or female) was ambivalent, a strong desire not to have children on the side of the other partner was often the deciding factor." 'Not finding a suitable partner at an appropriate time in life" was another deciding factor, particularly for ambivalent women.