Ovulation is coordinated by hormones, not a left-right rotation
Each menstrual cycle, hormonal signals prompt follicles—small fluid-filled structures in the ovaries, each containing an immature egg—to grow. Usually one follicle becomes dominant and releases its egg. The signals do not instruct the body to alternate ovaries, however, so the right or left ovary may be the one that ovulates in a given cycle. There is no dependable sequence to track.
How two eggs can be released
Sometimes more than one follicle matures enough to release an egg during the same cycle. Those eggs may come from one ovary or from both. This is called multiple ovulation; it is a variation in how follicles respond to the cycle’s hormonal signals, not a planned turn-taking pattern.
If two released eggs are each fertilized by a different sperm, both can implant and develop. The resulting fraternal twins are genetically like ordinary siblings, sharing roughly half their inherited DNA on average, rather than being genetic copies. Releasing two eggs does not guarantee twins: each egg must be fertilized, and each resulting embryo must continue developing.
The practical takeaway is that the side of an ovary cannot reliably predict which one will release an egg next—or whether a cycle will involve one egg or more.
