Around 2/3 of women experience shortness of breath as a part of a normal pregnancy. Neurological conditions such as spinal cord injury, phrenic nerve injuries, Guillain-Barre syndrome, amyotrophic lateral sclerosis, multiple sclerosis and muscular dystrophy can all cause an individual to experience shortness of breath.
On August 2, 1964, the U.S. destroyer Maddox exchanged shots with North Vietnamese torpedo boats in the Gulf of Tonkin. Two days later, the Maddox and another destroyer reported once again coming under fire.
On the morning of 4 August, U.S. intelligence intercepted a report indicating that the communists intended to conduct offensive maritime operations in the Gulf of Tonkin. In contrast to the clear conditions two days earlier, thunderstorms and rain squalls reduced visibility and increased wave heights to six feet.