Difference Between Ovarian Cycle and Menstrual Cycle

The key difference between ovarian cycle and menstrual cycle is that the ovarian cycle is the cycle that happens in the ovaries while the menstrual cycle is the cycle that happens in the uterus associated with the uterine wall.

Ovarian cycle and menstrual cycle are two cycles occurring in women. These two cycles prepare a woman to conceive and give birth to an offspring and become a mother. Both cycles occur in the female reproductive system. Thus, they are hormone responsive cycles. Females undergo these two cycles from puberty to menopause. The series of events take place during these two cycles, and they are mainly driven by the hormones. When the pregnancy occurs, both cycles will stop, and this is done by the hormone called human chorionic gonadotropin (hCG).

1. Overview and Key Difference
2. What is Ovarian Cycle
3. What is Menstrual Cycle
4. Similarities Between Ovarian Cycle and Menstrual Cycle
5. Side by Side Comparison – Ovarian Cycle vs Menstrual Cycle in Tabular Form
6. Summary

What is Ovarian Cycle?

Ovarian cycle is the cycle which happens in the ovaries. It consists of many events such as dynamic formation, growth, and ovulation of ovarian follicles and their transition, etc. This cycle governs by the combinational and sequential actions of several hormones including FSH, LH, progesterone, androgen, estradiol, and insulin.

Difference Between Ovarian Cycle and Menstrual Cycle

Figure 01: Ovarian Cycle and Menstrual Cycle

There are three phases in the ovarian cycle that run several days per cycle. They are a follicular phase (12 to 14 days), periovulatory phase (3 days) and luteal phase (14 to 16 days). The average length of the ovarian cycle is approximately 27 – 29 days in a healthy woman. However, it can range from 23 to 34 days.

What is Menstrual Cycle?

Menstrual cycle is the cycle that occurs in the uterus. It is also a cycle that takes place monthly with an average duration of 28 days. Uterine wall prepares for the possibility of an egg to be fertilized and settle in the uterus.

Key Difference Between Ovarian Cycle and Menstrual Cycle

Figure 02: Menstrual Cycle

Furthermore, it prepares for the supply of nutrients to developing embryo inside the uterus if the woman gets pregnant. If it not occurs, the developed uterine mucous membranes die and come out through the vagina. It is the phase called menstruation that lasts for 3 to 5 days. The other two phases of the menstrual cycle are a proliferative phase and the secretory phase. When the one cycle completes, the next cycle starts. This cycle is driven by the hormones produced from the ovarian cycle.

What are the Similarities Between Ovarian Cycle and Menstrual Cycle?

Both Ovarian Cycle and Menstrual Cycle are hormones driven.
Both occur in females.
They are associated with the female reproductive system.
Furthermore, both cycles are related to fertilization.
Hormones produced during the ovarian cycle affect the menstrual cycle.
Both cycles stop when the pregnancy occurs.
Hormone hCG is responsible for the stopping of both ovarian cycle and menstrual cycle.
The average duration of both cycles is 28 days.

What is the Difference Between Ovarian Cycle and Menstrual Cycle?

Ovarian cycle occurs in the ovaries whereas menstrual cycle occurs in the uterus. During the ovarian cycle, several events occur such as hormone release, follicle development and ovulation. On the other hand, during the menstrual cycle, the growth of the endometrial tissue, blood supply to the tissue and the cut off when implantation does not occur, and the shed of the developed tissues occur.

The below infographic presents the difference between ovarian cycle and menstrual cycle in tabular form.

Summary – Ovarian Cycle vs Menstrual Cycle

The cycle that occurs in the ovaries is the ovarian cycle whereas the cycle that occurs on the uterus is a menstrual cycle. Hormone release, follicle development, maturing and release of the egg are the main events of the ovarian cycle. Menstruation, the growth of uterine wall and cut off the blood and nutrient supply to the uterine wall are the main events of the menstrual cycle. Both cycles prepare a woman for a pregnancy, but both cycles stop when the pregnancy occurs. This is the difference between ovarian cycle and menstrual cycle.