What developments have begun to affect attitudes regarding the roles of women?
Since this is categorized under religion, I'm assuming you mean the roles of women in religious organizations. These are affected by and affect secular society. Those societies in which there is extreme gender separation or inequality in society as a whole tend to have similar patterns in religious practices while societies with greater gender equality in civic society also have greater gender equality in religious beliefs and practices.
In ancient Greece and India, for example, gender roles were quite distinct and women and men often socially segregated by gender. In such societies, there often were separate rituals, often associated with childbirth and mourning, performed by women, while other religious tasks were exclusively male.
In early Christianity, women would act as deaconesses and in Celtic Christianity (until the seventh century Synod of Whitby) there were mitred abbesses equivalent in authority to bishops. Protestantism, in its anti-clericalism and assertion of the priesthood of all believers, generally opened up a wider role for women than is found in Roman Catholicism with its emphasis on clerical authority. The combination of increasing gender equality and religious liberalization of the nineteenth century led to greater gender equality in western religions.
In the twentieth and twenty-first century, many Protestant denominations have achieved complete gender equality, due to a combination of belief in social justice and a religious movement which tends to read scriptural texts less literally and more as susceptible to different interpretations for different periods. The shortage of male vocations and the sex scandals that have rocked the Roman Catholic Church have caused it to open a wider range of lay ministries to women.