Caviar is considered a luxury food, fetching up to hundreds of dollars per ounce for the most exclusive grades. But if you think caviar is expensive, consider that human eggs cost around $3,000 each at the low end, and much higher if you want to use a donor with good genetics.Recently, Mitinori Saitou’s lab at Kyoto University published a paper (Nosaka et al., Developmental Cell 2025)1 describing a method to mass-produce mouse eggs from stem cells, at up to 400,000 eggs per batch. Although the e...