How large is a mature follicle?
Disease description:
I am currently trying to conceive and have been monitoring my follicles for some time. I just want to know how large a follicle needs to be in order to be considered mature. I'd like to have a general idea so I know when to have intercourse to increase my chances of conception.
Doctor's answer (1)
Dr. Zhang Lu
Under ultrasound monitoring, follicles are usually considered mature when their diameter reaches 18-25mm.
Ovarian follicle development is a continuous process, gradually progressing from primordial follicles to antral follicles, and finally developing into mature follicles. Following the start of the menstrual cycle, follicles gradually enlarge under the influence of gonadotropins and other hormones.
When the follicle reaches a diameter of approximately 18mm, the oocyte within has generally completed its maturation process and is capable of being fertilized. When the follicle reaches a diameter of about 25mm, ovulation may occur at any time in most cases.
However, the size indicating follicle maturity is not absolutely fixed. Some women may have mature follicles and achieve successful ovulation when the follicle size is around 17mm, while others may experience ovulatory dysfunction even when the follicle exceeds 25mm in diameter.
Doctors typically consider multiple factors including follicular morphology, tension, and hormonal changes such as estrogen and luteinizing hormone (LH) levels to comprehensively assess follicular maturity, thereby providing more accurate guidance for conception planning.
