luteinizing hormone surge
The rapid increase in LH levels that triggers ovulation, monitored in natural cycles and controlled in fertility treatments.
Full Definition
The luteinizing hormone surge refers to the dramatic increase in serum LH levels that occurs approximately 24-36 hours before ovulation in natural menstrual cycles. This surge is triggered by rising estradiol levels and positive feedback mechanisms, leading to final oocyte maturation and follicular rupture. In fertility treatments, the LH surge is often prevented using GnRH antagonists and replaced with controlled timing using hCG or GnRH agonist triggers to optimize oocyte retrieval timing. Detection of the natural LH surge can be accomplished through blood tests or urine ovulation prediction kits, making it a crucial parameter for timing natural conception attempts and monitoring cycle progression.
Usage
Usage note: Often abbreviated as LH surge; distinguish from other hormonal surges.
In Context
- "The patient's luteinizing hormone surge was detected on cycle day 14, indicating imminent ovulation." — Cycle monitoring report
- "GnRH antagonist was administered to prevent premature luteinizing hormone surge during stimulation." — Treatment cycle documentation