The introduction of cervical screening programmes and treatment of pre-cancerous cells has produced a profound decrease in the incidence of cervical cancer. Cold knife conisation, laser ablation, laser conisation, and large loop excision of the transformation zone (LLETZ) are all conservative methods of treatment used to remove or destroy abnormal cells and preserve cervical function at the same time. The techniques are equally successful at preventing progression to cervical cancer, however, data for future fertility and pregnancy outcomes have been conflicting.
To investigate, Maria Kyrgiou (Royal Preston Hospital, UK and University Hospital of Ioannina, Greece) and colleagues combined the results from 27 studies. They found that cold knife conisation increased the relative risk of preterm delivery, low birthweight, and caesarean section rate. LLETZ increased the relative risk of preterm delivery, low birthweight, and a woman's membranes rupturing prematurely. Laser conisation also had similar adverse effects although not to the same extent. The investigators did not detect increased risks for pregnancy outcomes after laser ablation. The outcomes for LLETZ are especially important, state the authors, because it is now by far the most popular treatment for cervical intraepithelial neoplasia.
Dr Kyrgiou states: "In summary, evidence clearly indicates that excision of the transformation zone is associated with a small but real increase in risk of pregnancy-related morbidity. This information should be considered when counselling women before their consent to treatment and lends support to the philosophy of doctors not treating young women with mild abnormalities."
"Our findings could probably favour the initiation of cervical screening after the age of 25 years with respect to long-term obstetric outcomes," she adds.
Contact: Dr Maria Kyrgiou, Department of Obstetrics & Gynaecology, Queen Charlotte's and Chelsea Hospital, Hammersmith Hospitals, Du Cane Road, W12 0TR, London, UK. T): 07725623604 mkyrgiou@yahoo.com
Notes to editors
Cold knife conisation - uses a scalpel to remove a cone shaped wedge of
tissue containing the abnormal cells.
Laser ablation - uses a laser to destroy the abnormal cells.
Laser conisation - uses a carbon dioxide laser to remove a cone shaped wedge of tissue containing the abnormal cells.
Large loop excision of the transformation zone (LLETZ) - uses a small tool and electric current to remove the area containing abnormal cells (the transformation zone) from the cervix.
Journal
The Lancet