Interesting that they call the centre where they "process" the Handmaids the Rachel and Leah Centre.
Rachel and Leah were married to the same man in the bible. Rachel had many years not conceiving, while Leah birthed six sons and a daughter.
Rachel was meant to be the first bride, but Leah was substituted at the last minute, and both believed that birthing sons would bring them closer to god. And Rachel offered her own Handmaid to her husband to bear children for him too.
Rachel and Leah were sisters and rivals, so I suppose that's a good similarity to how the wives and handmaids are seen by Gilead.