The levels of luteinizing hormone (LH) rise just before ovulation, and the increase triggers the release of an egg from an ovary. Just after this LH surge, the most fertile period of the menstrual. The LH surge is triggered by rising estrogen levels from maturing ovarian follicles. For most of the menstrual cycle, estrogen actually suppresses LH release. But when estrogen climbs high enough and stays elevated long enough, the brain flips from suppressing LH to actively stimulating a massive release of it. This switch from negative to positive feedback is the central event that causes. What an LH surge reveals about ovulation timing, how to test for it, and what high or absent LH really means, explained with medical evidence, not myths. Around the midpoint of your cycle, levels of luteinizing hormone (LH) surge. This marks the start of your fertility window. Luteinizing hormone and fertility What if you learned there was a marker. Knowing when your LH surge happens can be crucial information for those trying to conceive and make the most of their fertile window. Thinking if LH surge and ovulation are related? If one triggers the other? Let’s find out how LH surge impacts ovulation and pregnancy in this detailed guide. Luteinizing hormone (LH) helps regulate important functions of your reproductive system. Learn what it does in your body. What the LH surge is, how ovulation predictor kits detect it, how long it lasts, and how to time intercourse — a positive OPK means ovulation is near. Luteinizing hormone (LH, also known as luteinising hormone, [1] lutropin and sometimes lutrophin[2]) is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. [3] In females, an acute rise of LH known as an LH surge, triggers ovulation [4] and development of the corpus luteum. The LH peak is the highest point of that surge, typically occurring 24 hours before egg release. Ovulation usually happens within 24–36 hours of the LH surge beginning and about 24 hours after the LH peak. The best time to have sex is two days before ovulation day and the day of ovulation itself. What is an LH surge and what does it mean for ovulation? How to detect your surge, when to test, conception timing, and the fertile window explained.