When did I ovulate and how long is the egg viable for, given my luteinizing hormone (LH) surge on cycle day (CD) 13, peak LH level on CD14, and symptoms such as cramps, egg white cervical mucus (EWCM), nipple sensitivity, and body warmth?

Timing of Ovulation Based on Your Hormone Data

Based on your LH surge pattern, you most likely ovulated in the early morning hours of CD14 (approximately 24-36 hours after your LH surge began on CD13), and the egg remains viable for approximately 12-24 hours after release. 1, 2

When Your LH Surge Began

Your LH surge clearly started on CD13 evening (6:15 PM), when your LH jumped from 12.3 (FMU) to 26.7. 1, 2

• The onset of the LH rise is the most accurate marker for predicting ovulation timing, more reliable than the LH peak itself 2
• Your LH continued rising through CD14, peaking at 45 at an unspecified time, then declining to 22 by 7:30 PM and 12.1 by 10:30 PM 2

When Ovulation Occurred

Ovulation most likely occurred between 22-36 hours after your LH surge began on CD13 evening, placing it in the early morning hours of CD14 (approximately 4:00 AM - 6:00 PM on CD14). 1, 2

• Research shows ovulation occurs 28-36 hours after the beginning of the LH rise, or 8-20 hours after the LH peak 1
• Laparoscopic studies confirm that no ovulation occurs before 34 hours post-LH surge onset, but 50% of women ovulate between 37-39 hours 2
• Your cramps at 2:00 AM on CD15 (the "pulling achy cramps" lasting one hour) likely represent post-ovulatory cramping, not the moment of ovulation itself 1

Supporting Evidence from Your Hormones

Your estrogen (E1G) and progesterone (PDG) patterns confirm ovulation timing:

• E1G peaked at 258.6 on CD15, which is typical as estrogen drops sharply 12 hours before ovulation then rises again post-ovulation 1
• PDG remained low (1.1-1.6) through CD15, which is expected since progesterone doesn't rise significantly until 24-48 hours after ovulation 1
• Your declining LH on CD14 evening and CD15 (from 45 down to 13.2-18.6) confirms the surge had passed 3

Egg Viability Window

The egg remains viable for fertilization for only 12-24 hours after release. 1

• This is a critical but narrow window
• Sperm can survive 3-5 days in fertile cervical mucus, which is why intercourse before ovulation is actually more effective than after 4
• Your egg white cervical mucus (EWCM) on CD13-14 provided the optimal environment for sperm survival 1

Clinical Interpretation of Your Symptoms

Your physical symptoms align perfectly with the ovulation timeline:

• EWCM on CD13-14: Peak fertility sign occurring at the right time 1
• Cramps on CD14 and 2:00 AM CD15: Common periovulatory symptoms, though the CD15 cramps were likely post-ovulatory 1
• Nipple sensitivity, erect nipples, flushed cheeks, body warmth on CD15: These are post-ovulatory progesterone-mediated symptoms 1

Common Pitfalls to Avoid

• Don't assume the LH peak is the moment of ovulation - ovulation occurs 8-20 hours after the peak, not at the peak itself 1
• Don't rely solely on cramps to time ovulation - they can occur before, during, or after ovulation and are not precise markers 1
• Don't wait for basal body temperature shift - this is a retrospective marker that confirms ovulation already occurred 1-2 days prior 1

Optimal Timing for Conception

For future reference, intercourse or insemination should occur within 24-30 hours after LH surge detection for optimal pregnancy rates. 5

• In your case, this would have been CD14 morning through evening
• The fertile window extends from 5 days before ovulation through 1 day after, but the highest pregnancy rates occur with intercourse 1-2 days before ovulation 4, 5