LPH is the US Navy hull classification symbol for Landing Platform, Helicopter—amphibious assault ships of the Iwo Jima class. No ships of this class are currently in active service with the United States Navy:

• (LPH-2) USS Iwo Jima
• (LPH-3) US Okinawa
• (LPH-4) USS Boxer (Formerly CV-21)
• (LPH-7) USS Guadalcanal
• (LPH-9) USS Guam
• (LPH-10) USS Tripoli
• (LPH-11) USS New Orleans
• (LPH-12) USS Inchon

Note that there is another US Navy amphibious assault carrier named USS Iwo Jima (LHD-7), but they are entirely different vessels. The USS Iwo Jima in question is the only one of the LPH Iwo Jima class.