What is the normal size range of the uterus in millimeters?

In daily life, uterine size can affect a woman’s normal fertility. So, what is the normal range of uterine size in millimeters?

What is the normal range of uterine size (in mm)?

The normal uterus measures approximately 5.5–7.5 cm in length, 4.5–5.5 cm in width, and 3–4 cm in thickness; the cervix is typically 2.5–3 cm long. Generally, the sum of these three uterine dimensions is about 12 cm. The uterine cavity is shaped like an inverted triangle and has a depth of approximately 6 cm. An enlarged uterus may result from conditions such as uterine fibroids, adenomyosis, or uterine sarcoma. A smaller-than-normal uterus is often due to congenital uterine hypoplasia and may be associated with symptoms including oligomenorrhea (scanty menstruation), amenorrhea (absence of menstruation), or infertility. Thus, uterine size is critically important for women’s reproductive health. If a small uterus is identified during puberty, pharmacological treatment may be considered.

In adolescent girls with a small uterus but regular menstrual cycles and normal menstrual flow, no specific clinical intervention is required. After entering puberty, a relatively small uterus is considered a normal physiological phenomenon—especially in those who have not yet conceived. However, if an adolescent girl presents with a small uterus accompanied by absent or irregular menstruation, impaired ovarian development, or delayed development of secondary sexual characteristics, further clinical evaluation and appropriate management are warranted. Hormonal assays can assess ovarian function, while pelvic ultrasound can evaluate uterine morphology and dimensions.

Regular follow-up examinations are essential during treatment. I hope this response has been helpful to you. Wishing you good health and happiness!