Women's Entrepreneurship and Economic Empowerment Act of 2018 This bill modifies U.S. Agency for International Development (USAID) programs to provide targeted assistance for women. USAID strategies and projects shall be shaped by analysis to address gender differences, including how results may be different for men and women due to issues such as gender roles and structural barriers. The President is authorized to provide programs in developing countries for micro, small, and medium-sized businesses, particularly those owned, managed, and controlled by women. Previously, authorization for such programs was largely limited to microenterprises. The President is also authorized to provide targeted assistance programs that promote economic empowerment of women, including through increased access to financial resources, improving property and inheritance rights, and other legal protections. For sustainable poverty-focused programs, half of resources targeting micro, small, and medium-sized enterprises shall be for activities that reach the very poor. Half of resources for programs for small and medium-sized enterprises shall be for activities targeting enterprises owned, managed, or controlled by women. The bill directs USAID to modify its system for monitoring its programs to include outcomes broken down by gender, when feasible. The President is authorized to expand the micro and small business development credit program to provide such assistance to medium-sized businesses as well. The bill also directs USAID to break down various information in its annual report by gender and income level. USAID shall also report to Congress on the implementation of this bill. The Government Accountability Office shall report to Congress an assessment of the effect of development assistance for micro, small, and medium-sized enterprises in developing countries, and the extent to which such aid benefits women and the very poor.