The cervix is part of the female reproductive system, which also includes the fallopian tubes, uterus (womb), ovaries, vagina (birth canal) and vulva (external genitals).
The cervix, also called the neck of the uterus, connects the uterus to the vagina. It has an outer surface that opens into the vagina and an inner surface that faces into the uterus.
The cervix has a number of functions, including these:
- producing moisture to lubricate the vagina, which keeps the vagina healthy
- opening to let menstrual blood pass from the uterus into the vagina
- producing mucus that helps sperm travel up the fallopian tube to fertilise an egg that has been released from the ovary
- holding a developing baby in the uterus during pregnancy by remaining closed, then widening to let a baby be born through the vagina.
The cervix has an outer surface that opens into the vagina (ectocervix) and an inner surface that lines the cervical canal (endocervix). These two surfaces are covered by two types of cells: squamous and glandular
Squamous cells are flat, thin cells that cover the outer surface of the part of the cervix that opens into the vagina (ectocervix). Cancer of the squamous cells is called squamous cell carcinoma.
Glandular cells are column-shaped cells that cover the inner surface of the cervix (cervical canal or endocervix). Cancer of the glandular cells is called adenocarcinoma.
The area where the squamous cells and glandular cells meet is called the transformation zone. This is where most cervical cancers start.
About cervical cancer
Cervical cancer begins when abnormal cells in the lining of the cervix grow uncontrollably.
Cancer most commonly starts in the area of the cervix called the transformation zone, but it may spread to tissues around the cervix, such as the vagina, or to other parts of the body, such as the lymph nodes, lungs or liver.
There are two main types of cervical cancer, which are named after the cells they start in:
- squamous cell carcinoma
A small number of cervical cancers feature both squamous cells and glandular cells. These cancers are known as adenosquamous carcinomas or mixed carcinomas.
Other rarer types of cancer that can start in the cervix include small cell carcinoma and cervical sarcoma.
Squamous cell carcinoma
The most common type of cervical cancer, squamous cell carcinoma (often shortened to SCC) starts in the squamous cells of the cervix. It accounts for about seven out of ten – or 70 per cent – of cases.
Adenocarcinoma is less common type, making up about one in every four cases or 25 per cent. It starts in the glandular cells of the cervix. Adenocarcinoma is more difficult to diagnose because it occurs higher up in the cervix and the abnormal glandular cells are harder to find.
How common is it?
About 850 people in Australia are diagnosed with cervical cancer every year. Cervical cancer accounts for about 2 out of 100 (2 per cent) of all cancers diagnosed in people with a cervix. It is more common in people over 30, but it can occur at any age. About one in 195 people will develop cervical cancer before the age of 75.
The incidence of cervical cancer in Australia has decreased significantly since a national screening program was introduced in the 1990s and a national HPV vaccination program was introduced in 2007.
What are the symptoms?
In its early stages, cervical cancer usually has no symptoms.
The only way to know if there are abnormal cells in the cervix, which may develop into cervical cancer, is to have a cervical screening test.
If symptoms are present, they usually include these:
- vaginal bleeding between periods, after menopause or during or after sexual intercourse
- pelvic pain
- pain during sexual intercourse
- an unusual vaginal discharge
- heavier periods or periods that last longer than usual.
Although these symptoms can also be caused by other conditions or medicines, it is very important to rule out cervical cancer. See your doctor if you are worried or the symptoms are don’t go away. This is important for anyone with a cervix, whether straight, lesbian, gay, bisexual, transgender or intersex.
Almost all cases of cervical cancer are caused by an infection called human papillomavirus (HPV). There are also other known risk factors.
Infection with human papillomavirus (HPV)
HPV is the name for a group of viruses. HPV is a common infection that affects the surface of different areas of the body, such as the cervix, vagina and skin.
There are more than 100 different types of HPV, including more than 40 types that affect the genitals . Genital HPV is usually spread from the skin during sexual contact. About four out of five of all people will become infected with at least one type of genital HPV at some time in their lives. Some other types of HPV cause common warts on the hands and feet.
Most people will not be aware they have HPV as it is usually harmless and doesn’t cause symptoms. In most people, the virus is cleared quickly by the immune system and no treatment is needed. In some people with a cervix, the infection doesn’t go away and they have an increased risk of developing changes in the cervix. These changes usually develop slowly over many years.
Approximately fifteen types of genital HPV cause cervical cancer. Screening tests are used to detect these types of HPV or the pre-cancerous cell changes caused by the virus. See more information on screening tests . There is also a vaccination against HPV.
National HPV Vaccination Program
The HPV vaccine used in Australia protects against nine strains of HPV known to cause around 90 per cent of cervical cancers.
The vaccine also offers some protection against other less common cancers associated with HPV, including vaginal, vulvar, penile, anal and oropharyngeal cancers.
As part of the national HPV vaccination program, the vaccine is free for all children aged 12–13.
People who are already sexually active may still benefit from the HPV vaccine. Ask your doctor for more information. The HPV vaccine does not treat pre-cancerous cell changes or cervical cancer.
If you’ve been vaccinated, you will still need regular screening tests as the HPV vaccine does not provide protection against all types of HPV.
For more information, visit hpvvaccine.org.au.
Pre-cancerous cervical cell changes
Sometimes the squamous cells and glandular cells in the cervix start to change. They no longer appear normal when they are examined under a microscope.
These early cervical cell changes may be pre-cancerous. This means there is an area of abnormal tissue (a lesion) that is not cancer, but may lead to cancer. Only some people with pre-cancerous changes of the cervix will develop cervical cancer.
Pre-cancerous cervical cell changes are caused by certain types of the human papillomavirus (HPV). These cervical cell changes don’t have symptoms but can be found during a routine cervical screening test.
There are two main types of cervical cell changes:
- abnormal squamous cells
- abnormal glandular cells.
Abnormal squamous cells
These are called squamous intraepithelial lesions (SIL). They can be classified as either low grade (LSIL) or high grade (HSIL). SIL used to be called cervical intraepithelial neoplasia (CIN), which was graded according to how deep the abnormal cells were within the surface of the cervix:
- LSIL, previously graded as CIN 1, usually disappear without treatment
- HSIL, previously graded as CIN 2 or 3, are pre-cancerous. High-grade abnormalities have the potential to develop into early cervical cancer over ten to fifteen years if they are not found and treated. They can often be treated without affecting fertility.
Abnormal glandular cells
These are called adenocarcinoma in situ. They will need treatment to reduce the chance they develop into adenocarcinoma. Anyone with abnormal glandular cells in the cervix should be referred to a gynaecologist for a colposcopy.
Treating pre-cancerous cervical cell changes will prevent them developing into cervical cancer.
There are several risk factors for cervical cancer.
Smoking and passive smoking
Chemicals in tobacco can damage the cells of the cervix, making cancer more likely to develop in people with a cervix who also have a human papillomavirus (HPV) infection.
Long-term use of oral contraceptive (the pill)
Research has shown that women who have taken the pill for five years or more are at increased risk of developing cervical cancer. The reason for this is not clear. The risk is small and the pill can also help protect against other types of cancer, such as uterine and ovarian cancers. Talk to your doctor if you are concerned.
Having a weakened immune system
The immune system helps rid the body of human papillomavirus (HPV). People with a weakened immune system are at increased risk of developing cervical cancer and need to have more frequent cervical screening tests. This includes peoplewith the human immunodeficiency virus (HIV) and people who take medicines that lower their immunity. Ask your doctor if this applies to you and how often you should have a screening test.
Exposure to diethylstilbestrol (DES)
This is a synthetic (artificial) form of the human sex hormone oestrogen. DES was prescribed to pregnant women from the 1940s to the early 1970s to prevent miscarriage. Studies have shown that the daughters of women who took DES have a small but increased risk of developing a rare type of cervical adenocarcinoma.
Health professionals you may see
Your doctor will arrange the first tests to assess your symptoms. If these tests do not rule out cancer, you will be referred to a specialist, such as a gynaecologist or gynaecological oncologist. The specialist will arrange further tests.
If cervical cancer is diagnosed, the specialist will consider treatment options. Often these will be discussed with other health professionals at what is known as a multidisciplinary team (MDT) meeting. During and after treatment, you will see a range of health professionals who specialise in different aspects of your care.. The table below describes the roles of the people who may be in your MDT.
||specialises in treating diseases of the female reproductive system; may diagnose cervical cancer and then refer you to a gynaecological oncologist
||diagnoses and performs surgery for cancers of the female reproductive system (gynaecological cancers), such as cervical cancer
||treats cancer by prescribing and overseeing a course of radiation therapy
||treats cancer with drug therapies such as targeted therapy, chemotherapy and immunotherapy
||analyses x-rays and scans; an interventional radiologist may also perform a biopsy under ultrasound or CT, and deliver some treatments
|cancer care coordinator
||coordinates your care, liaises with MDT members, and supports you and your family throughout treatment; may be a clinical nurse consultant (CNC) or clinical nurse specialist (CNS)
||administers drugs and provides care, information and support throughout treatment
||recommends an eating plan to follow during treatment and recovery
|social worker, psychologist
||links you to support services; helps with emotional and practical problems associated with cancer and treatment
| women’s health physiotherapist
||treats physical problems associated with treatment for gynaecological cancers, such as bladder and bowel issues, sexual issues and pelvic pain
Expert content reviewers:
Associate Professor Penny Blomfield, Gynaecological Oncologist, Hobart Women’s Specialists, and Chair, Australian Society of Gynaecological Oncologists, Tas; Karina Campbell, Consumer; Carmen Heathcote, 13 11 20 Consultant, Cancer Council Queensland; Dr Pearly Khaw, Consultant Radiation Oncologist, Peter MacCallum Cancer Centre, Vic; Associate Professor Jim Nicklin, Director, Gynaecological Oncology, Royal Brisbane and Women’s Hospital, and Associate Professor Gynaecologic Oncology, University of Queensland; Professor Martin K .Oehler, Director, Gynaecological Oncology, Royal Adelaide Hospital, SA; Dr Megan Smith, Program Manager – Cervix, Cancer Council NSW; Pauline Tanner, Cancer Nurse Coordinator – Gynaecology, WA Cancer & Palliative Care Network, WA; Tamara Wraith, Senior Clinician, Physiotherapy Department, Royal Women’s Hospital, Vic
The illustration on this page has been adapted from An abnormal Pap smear result – what this means for you (National Cervical Screening Program, 2006). Used by permission of the Australian Government.