Yes, You will need a valid passport to travel to and from Mexico for surgery.

ENTRY/EXIT REQUIREMENTS: For the latest entry requirements, visit the Embassy of Mexico’s website or contact the Embassy of Mexico at 1911 Pennsylvania Avenue NW, Washington, DC 20006, telephone (202) 736-1600, or any Mexican consulate in the United States.

Since March 1, 2010, all U.S. citizens – including children – have been required to present a valid passport or passport card for travel beyond the “border zone” into the interior of Mexico. The “border zone” is generally defined as an area within 20 to 30 kilometers of the border with the U.S., depending on the location. Regardless of the destination in Mexico; however, all U.S. citizens age 16 or older must present a valid U.S. passport book or passport card to re-enter the U.S. by land. A passport book is required to return to the United States via an international flight.

All U.S. citizens traveling outside of the United States by air, land or sea (except closed-loop cruises) are required to present a Western Hemisphere Travel Initiative (WHTI) compliant document such as a passport book or a passport card to return to the United States. Legal permanent residents in possession of their I-551 Permanent Resident card may board flights to the United States from Mexico. Travelers with passports that are found to be washed, mutilated or damaged may be refused entry to Mexico and returned to the United States. While passport cards and enhanced driver’s licenses are sufficient for re-entry into the United States by land or sea, they may not be accepted by the particular country you plan to visit; please be sure to check with your cruise line and countries of destination for any foreign entry requirements.

The U.S. passport card has been in full production since July 2008. Beginning March 1, 2010, Mexican Immigration began to accept the passport card for entry into Mexico by air; however, the card may not be used to board international flights in the U.S. or to return to the U.S. from abroad by air. The card is available only to U.S. citizens. Further information on the Passport Card can be found on our website. We strongly encourage all U.S. citizen travelers to apply for a U.S. passport well in advance of anticipated travel. U.S. citizens can visit the Bureau of Consular Affairs website or call 1-877-4USA-PPT(1-877-487-2778) for information on how to apply for their passports.

As of May 1, 2010, non-U.S. citizens with valid U.S. visas may enter Mexico with the U.S. visa, and do not have to obtain a Mexican visa.