This phenomenon has several explanations. Some of the girls, for whom the first place is a family and having children, time to get married while still in college. The other part, which is a priority for career postpone the formalization of marital relations and the birth of a child, preferring a civil marriage and fight for a place under the sun.
Often such a struggle and the building of a career and even excludes civil marriage - it simply has neither the strength nor the time. Agree that even in a civil marriage responsibilities wife remain the same, the woman should keep the house, taking care of the man with whom he lives. Therefore, many women refuse to long-term alliances in favor of work and all my free time to devote to it.
A woman has to spend more time and effort on something to achieve any tangible results in building their careers than men. Since it is traditionally more demand, and it must constantly prove their worth and show remarkable abilities to enter the top leadership of the company, enterprise.
The result is that when it achieves its goal, its age would no longer be young. Men usually by this time, start a family, because for them, unlike women, the family is not an obstacle in his career, and even - on the contrary.
It turns out that women choose a career and make it to 35 years, remain single. They have already sufficiently high self-esteem, which becomes a kind of filter through which passes a man who does not have a certain status.
Therefore, putting his first career goal in life, keep in mind that you may later have difficulty starting a family. Perhaps it makes sense to think about this before and put their work plans for a few years in time to get married and have children.