Ovulation bleeding: what it is, and how to know if you’re experiencing it

But first, what exactly is ovulation?

This post was updated on October 24, 2017

Ovulation occurs when an ovary releases an egg. The egg travels down the fallopian tube towards the uterus. If it’s not fertilized within 24 hours after it’s released, it will break down and will be shed two weeks later with your period.

So how do you know when ovulation is happening?

As ovulation approaches, your body produces more cervical fluid. You can see this fluid in your underwear when you use the bathroom. It becomes stretchier, clearer, and more wet and slippery — like a raw egg white. This fluid tends to “peak” about 1 to 2 days before ovulation, when estrogen is highest (1). A surge in luteinizing hormone (LH) occurs and triggers the egg to be released from the follicle 36 to 40 hours later (2). Some people recognize “mittelschmerz” — or ovulation pain — a sharp or cramp-like pain felt on either side of the lower abdomen, that can last a few hours or days (3).

Tracking your basal body temperature (BBT) can also allow you to detect ovulation — as progesterone rises to prepare the uterus for the implantation of a fertilized egg, it causes a slight increase in your BBT. You can also use ovulation prediction tests/kits (OPKs).

And for some people, ovulation comes with a bit a blood.

Spotting is any bleeding that happens outside of your regular period. Spotting during ovulation occurs in 3% of menstruating people — it’s considered a physiological response to the quick drop in estrogen right after ovulation, before progesterone has a chance to rise (4,5).

One study found that people who experience ovulation bleeding have higher levels of hormones — estradiol, progesterone, and LH — around ovulation (4).

Since we’re curious, we asked the Clue community if anyone had experienced ovulation bleeding. In my experience, ovulation bleeding appears as a very light red, almost pink-ish hue, within my fertile cervical fluid. Here are some other folks’ experiences:

“I learned about ovulation bleeding when I was trying to conceive. When it would happen, I would always be confused as to whether it was ovulation bleeding or implantation bleeding. It’s mostly a rare occurrence for me, since I don’t ovulate every cycle. For me, the months that I have ovulation bleeding I notice that my periods are lighter but my PMS cramps are stronger. During months when I don’t have it, my cycle is longer, my periods are heavier, and my breasts are more tender. I also tend to have more ovulation bleeding when I’m taking supplements that change my hormone levels.”
“A few months ago I experienced a small bleed during ovulation. It was so light I don’t know if I would even call it a bleed, more like spotting. Initially I freaked out. I track my periods and my symptoms rigorously so I wasn’t sure why it was happening. When I clicked into the Clue app to log this, I checked out the information page on bleeding and it says that spotting around ovulation is a normal phenomenon. I knew I was ovulating that day, so Clue helped me put two and two together. This really put my mind at ease. Even though I do experience slight ovulation pain, before I knew that some spotting was normal I was worried there could be something wrong. It’s happened to me the past three months now, so it’s become somewhat of a regular occurrence. Ovulation bleeding has definitely made me more aware of my fertile window, as it usually only happens on the day Clue predicts I will ovulate.”
“After my pregnancy and breastfeeding in the second cycle, it suddenly occurred — blood lines in the discharge. I’d never heard of it before and kind of freaked out while calling my OB/GYN, because I thought my irregular cycle history from my mid-twenties to thirty was back. The doctor quickly explained to me that what I was experiencing was ovulation bleeding, and happens to a lot of people with regular cycles. I felt calm again, but yet every time it happened I was still kind of perplexed by it. But I’m aware I’m ovulating, and learning more about my cycle and my fertile days makes me feel more secure with my body.”

There’s still a huge knowledge gap when it comes to menstrual cycle health and fertility.

Although the prevalence of consistent spotting around the time of ovulation is starting to be investigated, it is still unclear as to why it happens, and whether it is healthy or may be a sign of something to be addressed with a healthcare provider. There is currently no evidence that ovulation spotting is a cause for concern.

Irregular bleeding and inconsistent spotting can be a predictor of other underlying health issues. If you regularly bleed between periods or you experience unusual heavy bleeding between your periods, talk to your healthcare provider, as not all mid-cycle bleeding can be attributed to ovulation bleeding. Other causes of spotting include contraceptive use (birth control pill, IUDs, other hormonal contraceptives), pregnancy, fibroids, polyps, infections, physical uterine changes, bleeding disorders, and cancerous changes.

Sharing information and experiences of ovulation bleeding can create awareness and help prevent confusion.

Help us close the female health knowledge gap — talk about features of ovulation with your partners and friends. Or share your experience with Clue on Twitter or Instagram.

If you regularly bleed between periods or you experience unusual heavy bleeding between your periods, talk about it with your doctor.

Download Clue to track your fluids and learn more about what’s going on in your body.


1. Bigelow JL, Dunson DB, Stanford JB, Ecochard R, Gnoth C, Colombo B. Mucus observations in the fertile window: a better predictor of conception than timing of intercourse. Human Reproduction. 2004 Apr 1;19(4):889–92.

2. Behre HM, Kuhlage J, Gassner C, Sonntag B, Schem C, Schneider HP, et al. Prediction of ovulation by urinary hormone measurements with the home use ClearPlan Fertility Monitor: comparison with transvaginal ultrasound scans and serum hormone measurements. Hum Reprod. 2000;15(12):2478–82.

3. Won HR, Abbott J. Optimal management of chronic cyclical pelvic pain: an evidence-based and pragmatic approach. Int J Womens Health. 2010;2:263–77.

4. Dasharathy SS, Mumford SL, Pollack AZ, Perkins NJ, Mattison DR, Wactawski-Wende J, Schisterman EF. Menstrual bleeding patterns among regularly menstruating women. American journal of epidemiology. 2012 Feb 20;175(6):536–45.

5. Twiss JJ. A new look at abnormal uterine bleeding. Nurse Pract. 2013 Dec 10;38(12):22–30.