Abstract: During lactation the sow generally remains anestrus. However, lactational estrus and ovulation sometimes occurs under unusual circumstances. Practical outcomes of lactational estrus are reducing the interval between weaning and estrusand therefore the non-productive days in the herd. Although various techniques to induce lactational estrus have been performed through natural management of the animals or the use of exogenous hormones during lactation, induction of estrus during lactation has not been recommended for commercial use. The objective of this study was to review and analyze the basic lactating sow physiology and the different methodologies to induce lactational ovulation, in order to improve her reproductive and productive performance, as a possible alternative to the early weaning system, especially in those cases where lactation length is determined by welfare constraints.