First half of the human menstrual cycle, during which one or more follicles in the ovary may mature, culminating in ovulation.
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 757 (https://doi.org/10.1515/pac-2015-1202)