Complex sentence: This double consummation of her marriage resulted in two eggs, each of them hatching immortal twins: from the first egg Castor and Pollux, and from the second Clytemnestra and Helen.
Split into simpler sentences: This double consummation of her marriage resulted in two eggs, each of them hatching twins. From the first egg Castor and Pollux, and from the second Clytemnestra and Helen.