Uterine Cervix and Common Cervical Abnormalities

The cervix is the part of the inverted-pear shaped uterus that corresponds to the narrow stalk end of the pear. This cylindrical-shaped muscular structure is about 3-5cm in length and partly lies in the upper vagina, extending superiorly into the retroperitoneal space behind the bladder and in front of the rectum. It is supported by ligaments (cardinal ligaments laterally and uterosacral ligaments posterolaterally). The cervix opens into the uterine cavity superiorly (via the internal os) and into the vagina inferiorly (via the external os). It is mainly composed of involuntary muscle superiorly and fibrous connective tissue inferiorly. The cervix is lined in its upper 2/3 by ciliated, cylindrical epithelium which changes to stratified squamous epithelium at the external os. It receives its blood supply from the ovarian and uterine arteries (originating from the aorta and internal iliac arteries respectively). It has an autonomic (sympathetic and parasympatheitc) nerve supply and lymphatic drainage is to the external and internal iliac lymph nodes as well as the obturator node and the sacral nodes.

The cervix acts as a canal between the vagina and the body of the uterus. Numerous deep glandular follicles lining the mucus membrane of the endocervix are responsible for the production of mucus. This mucus changes consistency in response to the levels of oestrogen: it is profuse, watery and alkaline when levels are high but as levels drop post ovulation, it becomes thick, scant and acidic. During pregnancy, it becomes even thicker and more tenacious, forming a plug rich in leucocytes. Microglandular hyperplasia can occur during pregnancy and immediately postpartum as well as in women taking progesterone treatment.

General points

• Examination of the cervix should be carried out in conjunction with examination of the other associated structures.
• Whether you are male or female, have a chaperone.
• Always explain exactly what you are going to do at the outset.
• Prepare everything in advance so that there is no fumbling mid-examination.
• Encourage patient to empty her bladder before beginning examination.

Preparation: items required

• Comfortable couch.
• Sheet for the patient.
• Flexible light source.
• Non sterile gloves (double glove if you plan to then do a rectal examination).
• Warm running water.
• Vaginal speculum (place in warm water if metallic) - preferably more than one if different sizes available.
• Lubricating jelly.
• Any additional instruments you may need such as cervical smear kit.
• Consent from the patient (verbal is generally fine).

Examination

• Position the patient correctly: she should be lying on her back, heels drawn up towards her bottom and knees gently relaxing open.
• Warm the speculum and add lubricating jelly to it.
• Let the patient know that you are going to start.
• Examine the vulva, expose the introitus and insert the closed speculum.
• When the handles of the speculum are almost flush with the perineum, gently open it and position so that the cervix lies between the two arms of the speculum.
• Examine the cervix, making note of the shape of the os, uniformity of colour, any asymmetry, lumps or other abnormalities.
• Carry out a smear as appropriate.
• Gently pull the speculum back just enough to clear the cervix (1-2cm) then loosen the speculum before fully withdrawing it.
• The elusive cervix If the cervix is not immediately visible, don't withdraw immediately. Consider angling the blades of the speculum (anteriorly or posteriorly) until it comes into view. If it is partially concealed, a swab may be used to bring it fully out (it is essential to be able to see its entire circumference). The chaperone may also apply gentle pressure on the abdomen. If all of those fail, consider whether the size of the speculum is right (if it is too small, it will not reach the fornices). Lying the patient on her side is also used with varying success. If the view is still not adequte, abandon the procedure and either bring the patient back another day or refer to colposcopy clinic. Be sure to explain what is happening and why.

• Colposcopy In certain situations, a speculum examination is not enough (most commonly if abnormal cells are picked up on a routine smear test but also in cases of bleeding after intercourse, persistant severe vaginal discharge, intermenstrual bleeding and in immunocompromised patients) and the cervix is further assessed using a colposcope (a mounted binocular microscope). From the patient's perspective, this involves the same procedure as for a speculum examination although the procedure is longer and may involve application of acetic acid or iodine. A biopsy may also be taken and laser treatment carried out. Colposcopy can safely be carried during pregnancy but biopsies and treatment will be postponed until after the time of delivery.
• Other procedures Further assessment of the cervix is usually carried out in the context of suspicions of uterine abnormality in which case, hysteroscopy or laparoscopy may be indicated.

Congenital abnormalities²

These are relatively uncommon and occur as one of three problems: failure of fusion of the Müllerian ducts during development, congenital absence of the cervix and abnormalities arising as a result of in utero exposure to non-steroidal oestrogens (such as diethylstilbestrol).

Benign tumours

• Polyps^2,4 These are the most common benign neoplasms of the cervix (found in 4% of the gynaecological population). These may be endocervical or cervical. Endocervical polyps are most usually found in the fourth to sixth decade of life. They are cherry red lesions may be single or multiple and may appear as a pedunculated lesion on a stalk of varying length. Cervical polyps are equally benign and tend to occur as single, smooth grey-white lesions that bleed easily if touched. Polyps tend to be asymptomatic but may also present as abnormal bleeding (such as during intercourse, between menstrual periods or after the menopause). Occasionally, they may grow big enough to obstruct the external os and so cause infertility. Less than 1 in 200 cases become malignant; suspicious lesions should be removed in a specialist clinic and sent to histology.
• Fibroids (myoma / leiomyoma) These smooth, firm masses are often solitary and account for about 3-8% of uterine myomata.⁴ A fibroid growing down into the cervix from higher up in the uterus is a more common situation. They tend to be small (5-10mm in diameter): enlargement causes upward displacement of the uterus and the fibroid may become impacted. ¹ Other symptoms also relate to its size and exact location: dysuria, urgency, obstruction and dyspareunia.⁴ Management is guided by the size of the lesion and age of patient (with regards to whether she might want a future pregnancy). It ranges from simple observation to medical treatment with GnRH agonists to surgery. The latter is tricky on account of the relative inaccessibility of these lesions and the proximity to the bladder and ureters.
• More unusual abnormalities² There are a number of less common tumors which can arise around the cervix including squamous papillomata (2-5mm diameter tumours situated on the ectocervix, which may arise as a consequence of past infection or trauma), endometriotic spots (blue-red or blue-black lesions 1-3mm in diameter which may have been implanted during childbirth or surgery), papillary fibroadenomata, mesonephric duct remanents and very rarely, heterologous tissue (including cartilage, glia and skin) - most likely remnants of a previous abortion.

Abnormality of form

• Stenosis⁴ This problem may be congenital or acquired and tends to occur at the level of the internal os. Diathermy excision of cervical lesions is the most common cause of stenosis (it occurs in 1.3% of cases¹); other acquired causes include radiotherapy, infection, neoplasia and atrophy following a cone biopsy. It may also be associated with endometriosis. Pre-menopausal patients present with menstrual disorders, pain and infertility whereas post-menopausal may remain asymptomatic or develop symptoms over a very long period of time after which they may present with haematometra, hydrometra or pyometra. Diagnosis is made upon failure to introduce a 1-2mm dilator into the uterine cavity and confirmed when a large but painless palpable uterus is found. Teatment is with ultrasound guided dilators or with laminaria tents (where the dried out laminaria seaweed is packed into the cervix and slowly expands). Prostaglandin pessaries can be used to soften the cervix where access is needed for procedures such as hysteroscopy.¹
• Ectropion (previously called cervical erosion or abrasion)⁵ This is when the central columnar epithelium extends out through and around the external os. It is more commonly seen in teenagers, during pregnancy and in women on the oral contraceptive pill. It may also be seen in newborns. This is generally an asymptomatic condition (patients occasionally present with bleeding or infection) which is seen on examination as a red ring around the os. Once a normal cervical smear has been confirmed, it is actively managed only if there are symptoms. Options include thermal cautery with diathermy, cryotherapy and surgery with laser treatment.

Other problems of the cervix

• Nabothian cysts (epthelial inclusion cysts / mucinous retention cysts)⁶ These common mucus-filled lesions are almost considered to be a normal part of the adult cervix.⁴ They look like multiple translucent or opaque, white or yellow lesion ranging from 2mm to 10mm in size. They tend to occur following natural tissue regrowth after minor trauma or after childbirth. This new tissue grows over the opening of the nabothian glands, so giving rise to these lesions.They are occasionally a result of chronic cervicitis. They are asymptomatic and need no treatment. They may very occasionally be problematic if they grow very large in which case they may be treated with cautery or cryotherapy.
• Laceration This can occur following mechanical dilatation of the cervix, particularly where a softening agent (such as a prostaglandin) is not used appropriately. Thus, cervical lacerations can complicate hysteroscopy and abortion.¹ It occurs more commonly in the presence of cervical stenosis or atrophy and may also occur during delivery. Acute lacerations present with bleeding and need suturing once the extent of the laceration is ascertained. Poor repair may lead to subsequent cervical incompetence.⁴

This is usually diagnosed in the context of a miscarriage occurring after 12-14 weeks or in premature labour. It presents as a painless dilatation of the cervix through which the membranes bulge and eventually spontaneously erupt. Diagnosis is based on a past history of second-trimester miscarriages and ultrasound scanning may confirm shortening or funnelling of the cervix (although this in itself carries a risk of miscarriage ⁷). Treatment involves prophylactic placement of a cervical stitch (cerclage) with the aim to prevent loss of the pregnancy (an emergency procedure can also be carried out). However, there is controversy over the effectiveness of this procedure which may also be associated with an increased risk of peurpural pyrexia.^7,8

Infectious

Endocervicitis

• Symptoms: vary from none to abnormal yellow - green discharge, bleeding (especially post-coital), dysuria.
• Signs: green / yellow / opaque mucopurulant discharge. Endocervical friability (bleeds easily).
• Common culprits: Neisseria gonorrhoeae, Chlamydia trachomatis, herpes simplex virus.
• Treatment:¹⁰ anti-microbial depending on what is identified on swabbing. Uncomplicated gonorrhoea responds to a single oral dose of 500mg ciprofloxacin whereas Chlamydial infection should be treated with doxycycline (orally 100mg, bd for 7 days) in the first instance. Acyclovir (orally 200mg 5 times a day for 7 days) is appropriate for a herpes infection.

Ectocervicitis

• Symptoms: as with endocervicitis.
• Signs: cervical oedema and erythema, discrete ulceration, cervical petichiae ("strawberry cervix").
• Common culprits: cervical cancer, mechanical trauma, chemical irritants (douching, spermicides), systemic inflammatory disease such as Behcet's syndrome.
• Treatment: this will depend on causative factor.

There will also be a significant proportion of cervicitis of unknown aetiology. A cervical smear is mandatory in suspected non-infectious cervicitis.