Reproductive system
Uterus (Womb)
The uterus, or womb, is a muscular, pear-shaped organ in the female pelvis where a baby develops during pregnancy. Its lining also builds up and sheds each month as a period.
What it is
The uterus is a hollow, muscular organ about the size and shape of an upside-down pear, connecting to the vagina below and the fallopian tubes above.
Where it is
In the female pelvis, between the bladder and the rectum.
What it does
Houses and nourishes a developing baby during pregnancy, and — outside pregnancy — builds up and sheds its lining each menstrual cycle.
How it works
Each month the uterus lining thickens ready for a possible pregnancy. If no pregnancy occurs, the lining sheds as a period. During pregnancy the muscular walls stretch enormously and later contract powerfully in labour to deliver the baby.
When things go wrong
Common conditions affecting the uterus (womb)
- Heavy or painful periods
- Fibroids
- Endometriosis (affecting nearby tissue)
- Uterine (womb) cancer
Education and reference only. This explains the anatomy in plain terms and is not a diagnosis. Sudden severe symptoms — such as severe chest pain, breathlessness or collapse — are an emergency; call 999.
Looking after it
Keeping your uterus (womb) healthy
Attending cervical screening, getting abnormal bleeding checked, and discussing troublesome periods with a clinician support gynaecological health.
Did you know?
An interesting fact
During pregnancy the uterus grows from around the size of a pear to the size of a watermelon, then returns close to its original size afterwards.
Answers
Uterus (Womb): frequently asked questions
What does the uterus do?
The uterus (womb) houses and nourishes a developing baby during pregnancy, and sheds its lining each month as a period when there is no pregnancy.
What bleeding should be checked?
Bleeding between periods, after sex, or after the menopause should always be checked by a doctor.
The reproductive system
Related organs
Sources
Where this is drawn from
- NHS — Anatomy and body systems
- Gray's Anatomy for Students
- TeachMeAnatomy / TeachMePhysiology
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