They summoned the goddess Yogamaya and had her transfer the fetus through the womb of Devaki for the womb of Rohini (Vasudeva's other spouse who lived with her sister Yashoda over the river Yamuna, within the village of cowherds at Gokulam). So the child conceived in one womb was incubated https://digitalasset.sfo2.digitaloceanspaces.com/SouthernCaliforniaSurrogacy/Becoming-A-Surrogate-In-Southern-California.html