As of December 31, 2015, extra visa pages are no longer added to U.S. passports. Instead, 52-page passport books will be issued to U.S. citizens applying from outside the United States for the same price as 28-page passport books. Allow two weeks for processing new U.S. passports.
For more information you may refer to the U.S. Department of State website on passport applications. Please remember that some procedures for passport applications abroad may vary according to the country in which the passport application is made.