Howling:Amy and River. stomach pains

i noticed in the impossible astronaught both amy and river have hold their yet stomachs and say they feel sick. amy when she is in the oval office and just before the astronaught apears. ( she then tells the doctor she is pregnant). river when she goes back into the hole after forgeting about the silence down there.

is it possible that they are either linked or that river is also pregnant. we dont really have enuogh info to speculate about yet but what do people think. any ideas