When to start testing in your cycle

Day 1 is the first day of your period. To find your start day, subtract 17 from your cycle length.

Test once daily until you get a positive or your period starts.

Irregular cycles? Use your shortest recent cycle to calculate your start day. If unsure, begin on Day 8 and test daily.

What is the best time of day to take an ovulation test?

The ideal testing window is 10 AM - 8 PM. Here's why each time works:

Should you test at the same time every day?

Yes, if possible. Consistency helps you compare results. If you test at 2 PM every day, you can see the progression from negative → faint line → dark positive more clearly.

However, don't stress if you can't test at exactly the same time. Testing at 11 AM one day and 4 PM the next is fine—as long as you're within the 10 AM - 8 PM window, you'll catch your surge.

📅 Pick your testing time

Choose a time that fits your schedule and stick with it:

• Work from home? Test at 2 PM after lunch
• 9-5 office job? Test at 10 AM before work or 6 PM after
• Night shift? Test during your "afternoon" (midpoint of your waking hours)

Set a daily reminder on your phone so you don't forget.

💡 Quick takeaway
Test anywhere from 10 AM - 8 PM. Afternoon (2-5 PM) is ideal. Stay consistent if you can, but don't stress if your timing varies by a few hours.

Why you should NOT use first morning urine for ovulation tests

First morning urine (FMU) works perfectly for pregnancy tests, but it's problematic for ovulation tests. Here's why:

How LH surges work (and why timing matters)

Your pituitary gland releases a surge of luteinizing hormone (LH) 24-36 hours before ovulation. This surge:

• Begins in the early morning: Most LH surges start between 4 AM - 8 AM
• Takes hours to appear in urine: What's in your bloodstream takes 3-4 hours to show up in urine at detectable levels
• Peaks mid-day: LH levels in urine are typically highest between 10 AM - 8 PM, according to clinical research on urinary hormone ranges

The problem with first morning urine: That urine was produced overnight, from approximately 11 PM to 6 AM—before your LH surge began. Even if your surge started at 6 AM, your first morning pee won't show it yet.

Can LH surges happen at night?

Yes, but it's less common. Studies show that approximately 70% of LH surges begin in the morning (4 AM - 12 PM), with the remaining 30% starting afternoon or evening. This is why afternoon testing (10 AM - 8 PM) catches the majority of surges.

ALT: Chart showing LH levels in blood rising early morning and LH detectable in urine peaking from late morning to evening, illustrating why ovulation tests are most accurate when taken in the afternoon.

Should you test twice a day?

For most women, once-daily testing is sufficient. But consider testing twice daily (12 hours apart) if:

• You have short or irregular cycles: Your LH surge may be brief (10-14 hours), and once-daily testing could miss it
• You've tested for 3+ cycles and never got a positive: You might be catching the tail end or missing the peak
• You're using expensive treatments (IUI, IVF): Precision matters more when timing is critical

Best times for twice-daily testing

10 AM and 6 PM (8 hours apart, easier schedule) or 10 AM and 10 PM (12 hours apart, better coverage)

Twice-daily testing significantly increases your chances of catching short surges, but it also means using twice as many tests. Pregmate's affordable strip tests make this feasible without breaking the bank.

How long to hold pee before taking an ovulation test

For accurate results, follow these guidelines:

⚠️ False negatives from diluted urine
If you're getting faint lines or negative tests but think you should be ovulating, check your hydration. Women who drink 3+ liters of water daily or who test right after drinking a large glass of water often get false negatives.

Fix: Hold pee for 3 hours instead of 2, or test first thing after waking from a nap (if you didn't drink water beforehand).

💡 Quick takeaway
Don't pee for 2 hours before testing. Don't chug water for 2 hours before. Your pee should be medium yellow, not clear. These steps concentrate LH so the test can detect it.

Technical details: dipping, reading, and storing tests

How long to wait before reading results

Read at 5 minutes. Most ovulation tests stabilize at 3-10 minutes, but 5 minutes is the sweet spot according to clinical validation studies on LH detection methods:

• Before 3 minutes: Lines may still be developing
• At 5 minutes: Results are stable and accurate
• After 10 minutes: Evaporation lines can appear, causing confusion

Set a timer when you dip the test. Read it at exactly 5 minutes, then discard it to avoid second-guessing results later.

Does urine need to be room temperature?

No. You can test immediately after collecting urine—you don't need to let it cool or warm up. Fresh urine at body temperature works perfectly.

Some women prefer to let urine sit for 1-2 minutes if it's very fresh (straight from the body), as this can make lines easier to read, but it's not required.

Can you reuse urine from earlier?

Not recommended. LH can degrade in urine over time. If you must save urine (e.g., testing multiple brands), refrigerate it and use it within 2-4 hours. Bring it to room temperature before testing.

Special situations: night shifts, PCOS, and short surges

What if you work night shifts?

Test during your "afternoon"—the midpoint of your waking hours, not calendar time.

Example schedule:
You sleep 8 AM - 4 PM
You wake at 4 PM
Your "afternoon" is around 10 PM - 12 AM
Test at 10 PM (midpoint of your waking hours)

Avoid testing right after waking (your first pee) for the same reason: that urine was made while you were sleeping, before any surge began.

What if you have PCOS?

PCOS (polycystic ovary syndrome) can complicate ovulation testing. According to ASRM guidelines on optimizing fertility:

• Elevated baseline LH: Some women with PCOS have LH levels that are always somewhat elevated, causing faint lines every day
• Multiple surges without ovulation: LH may spike but not trigger egg release
• Irregular cycles: You may not know when to start testing

Strategy for PCOS:

• Start testing on Day 8 and test daily (or twice daily) until positive or period starts
• Look for a test line that's as dark or darker than the control line — not just "darker than yesterday"
• Confirm ovulation with basal body temperature (BBT) tracking to see if the surge actually resulted in ovulation
• Consider using advanced digital tests that measure both estrogen and LH

What if you never get a positive?

If you've tested for 3+ cycles and never seen a positive result:

• Check your testing time: Are you using first morning urine? Switch to afternoon
• Test twice daily: Your surge may be very short (10-12 hours)
• Try a more sensitive test: Pregmate detects LH at 25 mIU/mL; some brands require 40+ mIU/mL
• See your doctor: You may have anovulatory cycles (no ovulation) or very low LH levels. Blood tests can diagnose this

Frequently asked questions

Can you use first morning urine for an ovulation test?
No, it's not recommended. First morning urine was produced overnight before your LH surge began, so it won't show elevated LH even if you're surging. Test between 10 AM - 8 PM for best results.

What time of day is LH highest in urine?
LH is typically highest in the urine between 10 AM - 8 PM, with peak levels often occurring around 2 PM - 6 PM. This is because LH surges begin in the early morning, and it takes 3-4 hours for hormones to show up in urine at detectable levels.

How long should you hold your pee for an ovulation test?
Hold your urine for at least 2 hours before testing. This allows LH to concentrate in your bladder. Also avoid drinking excessive water for 2 hours before testing—normal hydration is fine, but don't chug water or your urine will be too diluted.

Can you take an ovulation test at night?
Yes, evening testing (6 PM - 8 PM) works well. Late night (9 PM - midnight) is okay but less ideal because urine may be more diluted. Avoid testing right before bed if you've been drinking fluids throughout the evening.

Complete timing checklist

• Test between 10 AM - 8 PM (afternoon 2-5 PM is ideal)
• Hold pee for 2 hours before testing
• Don't drink excessive water 2 hours before
• Check urine color (medium yellow, not clear)
• Dip test for 3-5 seconds
• Read result at 5 minutes
• Test at the same time daily if possible

• DON'T use first morning urine
• DON'T test right after drinking lots of water

Sources and references

• Ecochard, R., Duterque, O., Leiva, R., Bouchard, T., & Vigil, P. (2015). "Self-identification of the clinical fertile window and the ovulation period." Fertility and Sterility, 103(5), 1319-1325. https://doi.org/10.1016/j.fertnstert.2015.01.031 Study on timing of LH surges and optimal testing windows for ovulation detection.
• Johnson, S., Weddell, S., Godbert, S., Freundl, G., Roos, J., & Gnoth, C. (2015). "Development of the first urinary reproductive hormone ranges referenced to independently determined ovulation day." Clinical Chemistry and Laboratory Medicine, 53(7), 1099-1108. https://doi.org/10.1515/cclm-2014-1087 Established urinary LH thresholds and optimal timing for detection based on ovulation day.
• Su, H.W., Yi, Y.C., Wei, T.Y., Chang, T.C., & Cheng, C.M. (2017). "Detection of ovulation, a review of currently available methods." Bioengineering & Translational Medicine, 2(3), 238-246. https://doi.org/10.1002/btm2.10058 Comprehensive review of ovulation detection methods including LH testing accuracy and timing protocols.
• American Society for Reproductive Medicine (ASRM). (2023). "Optimizing Natural Fertility: A Committee Opinion." ASRM Practice Guidelines Clinical guidelines on fertility awareness methods and optimal timing for conception.
• McGovern, P.G., Myers, E.R., Silva, S., et al. (2004). "Absence of secretory endometrium after false-positive home urine luteinizing hormone testing." Fertility and Sterility, 82(5), 1273-1277. https://doi.org/10.1016/j.fertnstert.2004.04.070 Research on LH surge detection accuracy and factors affecting test reliability including timing and urine concentration.