Three women lacked LH surges. Mean LH surge: start = day 14.5 (±3.6 SD) (range: 9–26); peak = 41.2 mIU/mg creatinine (±20 SD) (range: 12.1–104.0); fold increase = 7.7 (±3.0 SD) (range: 2.5–14.8); duration = 7.6 days (±1.5 SD) (range: 5–11). The onset of LH surge was of two types: rapid onset (within 1 day) (42.9%) or gradual onset (2 to 6 days) (57.1%). Configurations of LH surges were of three types: spike (41.9%), biphasic (44.2%), or plateau (13.9%). All LH surges demonstrated a gradual decrease to baseline. Three women (7%) did not have FSH rises coincident with LH surges. All displayed E1C rises during the middle to late follicular phase.
Conclusion(s)
The LH surges that result in ovulation are extremely variable in configuration, amplitude, and duration. The FSH rise does not seem essential for ovulation. However, an E1C rise occurred in all cycles, confirming the critical role of estrogen in induction of the LH surge.
Key Words
LH surge
ovulation
menstrual cycle
luteinizing hormone
Cited by (0)
Supported by Pfizer/Society for Women's Health Research Scholars Grants for Faculty Development in Women's Health 2001, and American College of Obstetrics and Gynecology/Solvay Pharmaceuticals Research Award in Menopause 2005.
Poster presentation at the 88th Annual Scientific Meeting, Endocrine Society, Boston, Massachusetts, June 24–27, 2006.