MAIDAN SHAHR, Afghanistan—Palwasha didn’t get enough time to pick the names for her twins.

Her son died immediately after birth. Her daughter, born premature and weighing 700 grams, equivalent to 1½ pounds, was put into an incubator at the provincial hospital in Maidan Shahr. Breathing seemed to take all her strength, jerking her little body with each gasp. Two days later, she was gone, too.