Women who undergo a common treatment of the cervix are more likely to have a premature baby later in life, according to research out today.
The study found women who underwent loop excision, the most common treatment for removing precancerous cells of the cervix, had an increased risk of having an early baby.
When the results were combined with those from other studies, there was a clea
r association, the authors said. But laser ablation, where the cells are killed off by a laser, was not associated with increased risk.
Changes to the cells of the cervix can be picked up through a smear or "Pap" test.
Women who have an abnormal smear test result are usually invited to hospital for further investigation.
Treatment is then offered to remove any precancerous cells.
The paper, published in the January edition of the journal BJOG, owned by the Royal College of Obstetricians and Gynaecologists (RCOG), involved more than 5,000 women.
Researchers from Melbourne University and Royal Women's Hospital in Australia compared data for women who had undergone treatments for removing precancerous cells between 1982 and 2000.
The methods looked at by the researchers were loop excision (where an electrical current is passed around a wire in order to remove a tissue sample), cone biopsy (where tissue is removed with a cone-shaped blade), diathermy (where an electrical current is used directly on the tissue), and laser ablation (where the tissue is destroyed by a laser beam).
Loop excision, which is sometimes also referred to as LEEP, means the tissue can be examined for disease whereas a laser actually destroys it.
Laser ablation is also considered an expensive and tricky treatment, although studies have previously shown that both loop and laser have a similar success rate. All treatments other than laser ablation were found to be associated with increased risk.
This is the first time that a link has been made between loop excision and premature birth, the authors noted.
They also found that both treated and untreated women who had precancerous cells were at increased risk of premature birth, suggesting treatment was not the only risk factor.
They said: "Women presenting with precancerous changes in the cervix are at an increased risk for preterm birth, a risk that appears to be increased by treatments that remove or destroy substantial amounts of cervical tissue."
The RCOG said premature birth can cause long-term problems for the baby.
"Women need to know about the risks involved and discuss alternative treatments with their gynaecologist, before going ahead with a procedure that increases the risk of pre-term birth," it said.
It estimated that around 1,500 premature births each year in Britain could be prevented if a technique other than loop excision was used.
