Luteinizing Hormone Surge
The rapid increase in luteinizing hormone that triggers ovulation in natural and stimulated cycles.
Full Definition
The luteinizing hormone (LH) surge is a dramatic increase in LH secretion from the anterior pituitary that occurs approximately 36 hours before ovulation in both natural and stimulated cycles. This surge is the physiological trigger for final oocyte maturation, cumulus expansion, and follicle rupture. In assisted reproductive technology cycles, the timing of the LH surge is often controlled using GnRH agonists or antagonists to prevent premature ovulation. When natural LH surge is suppressed, ovulation is typically triggered with human chorionic gonadotropin (hCG) or GnRH agonist injections. Monitoring for LH surge through blood tests or urine kits is essential for timing procedures such as intrauterine insemination or oocyte retrieval.
Usage
Usage note: Specify whether natural or triggered when documenting LH surge.
In Context
- "The patient's luteinizing hormone surge was detected on cycle day 12, indicating impending ovulation." — Monitoring report
- "GnRH antagonist prevented premature luteinizing hormone surge during the stimulation cycle." — Treatment summary