Why Does Bleeding Occur Around Ovulation? A Clinical Perspective on Possible Causes and When to Seek Care

You may notice bleeding between periods and wonder whether it is related to ovulation or a sign of an underlying condition.

Bleeding around the time of ovulation is usually different from a menstrual period. It tends to be light and may appear as pink or brown discharge. In many cases, it resolves within two to three days around ovulation. This type of bleeding is thought to result from hormonal changes or minor bleeding from the ovary when the egg is released. It is referred to medically as ovulatory bleeding, and in most cases, it is a normal physiological occurrence that does not require treatment (*1).

*1: Source: Japanese Society of Psychosomatic Obstetrics and Gynecology

When Should You Seek Medical Advice?

However, not all bleeding between periods can be considered harmless. It is recommended to consult a gynecologist if bleeding lasts longer than one week, the amount is heavier than usual, the blood is bright red, or lower abdominal pain is strong and persistent.

Bleeding may be associated with various conditions, including hormonal imbalance, uterine fibroids, cervical or endometrial cancer, sexually transmitted infections, and vaginal inflammation.

Even if no abnormalities are found on an initial examination, repeated episodes of bleeding may indicate an early-stage condition that is not yet detectable. For this reason, follow-up and monitoring over time are important (*2).

*2: Source: Japan Society of Obstetrics and Gynecology

Ovarian Reserve and Ovulation

Another important point regarding ovulation is that the number of eggs gradually decreases over time. The total number of eggs is determined at birth, and both their quantity and quality decline with age.

For those who wish to have children in the future, egg freezing is one option that may be considered.

This procedure involves stimulating the ovaries with medication to develop multiple follicles, retrieving the eggs, and then rapidly freezing them. The eggs are stored in liquid nitrogen at −196°C, where they can be preserved for an extended period.

In general, egg retrieval is recommended before age 40, and the use of frozen eggs is typically recommended before age 50.

As fertility declines more rapidly around age 36, preserving eggs at a younger age may help maintain future reproductive options.

In recent years, companies such as Meta in the US, as well as Mercari and CyberAgent in Japan, have begun offering financial support for egg freezing as part of employee benefits, reflecting growing awareness of the need to balance career planning with future family planning.

If you have any concerns about bleeding between periods, or if you are considering preparation for future pregnancy, please do not hesitate to seek medical advice. A gynecologist can provide appropriate evaluation and guidance based on your situation.

The AMH test, which is often used to assess ovarian reserve, is also available. At our clinic, results are available in around 30 minutes.

Supervised by
Yuko Nagura, MD
Board-Certified Specialist, Japan Society of Obstetrics and Gynecology