Popular views of property rights and marriage created a situation in which women and slaves were not seen as truly independent people. Therefore, they were not really party to the social contract laid out in the Declaration of Independence.
The idea of the Declaration of Independence is that all white men are created equal. These are people who are responsible for themselves. They can enter into a social contract with the government because they are free agents. Therefore, they are to enjoy all of the freedoms set out in the Declaration.
By contrast, women and slaves were not free agents. Slaves were owned by other people and therefore dependent upon them. Women were, in essence, the wards of men just as children were. This meant that they, too, were not really competent to enter into a social contract. The social contract had to be set up between equals who were all competent to commit themselves to a contract. Slaves and women were the wards of others and therefore were not competent to do so.
Because slaves and women were not free and independent, they could not enter into the social contract and enjoy its benefits.
In 1776, The Declaration of Independence, a document that called for the freedom of the thirteen colonies of America, was signed. Drafted by Thomas Jefferson, this statement officially called for the separation of the thirteen colonies from their mother, Great Britain. The Second Continental Congress voted on the document on July 2nd, but signed the document on July 4th, which is why we celebrate the 4th of July in America instead of the 2nd.
The document outlined the many offenses that Britain committed against the colonies, the most prominent being the imposing of taxes without the colonies' consent, taking away the ability to have a trial by jury, the requirement of the colonies to quarter British troops, the drafting of the colonial citizens, the dissolving of Representative Houses, and the trade embargoes.
While the preamble of the Declaration is widely famous for being a statement on inherent human rights, the time period it was written in did not consider women and slaves to be very "human" at all. Both were considered property of the white men. Since the white men declared the rights for themselves, and did not declare them for slaves or women, the conditions of slavery and suppression of women did not change with the Declaration's signing.
Neither women nor slaves are "middle-upper class white men," so they were not granted the rights of the Declaration. Even lower class white men still struggled under the Declaration of Independence. While the Declaration helped to push against the tyranny of Great Britain, it did not help the domestic injustices happening to minorities and women.