I believe its LH as well, from my understanding LH causes the rupture of the follicle(secondary oocyte inside) and release of the secondary oocyte (now called ovum), ruptured follicle --> corpus LUTEUM
edit: this is the transition from ovulation @ the end of follicular phase and into luteal phase
I think your right, but in Barron's it says that after Meiosis I, the primary oocyte is dormant and it does not form a secondary oocyte until initiated by FSH (at puberty). Then comes Meosis II and the ovum.