System creating multiple out bound deliveries for a single purchase order

Hi Dear experts,

We need your help.

While generating out bound delivery for a single purchase order, system was generating multiple out bound deliveries even through items in the purchase order had similar shipping point, delivery date ,etc.Actually based on what aspects out bound deliveries will generated separately for a single PO.

Does the item number in the purchase order will impact in creating the out bound deliveries.

Please suggest.