Gynecologic Oncology Consult

Risk for obstetric complications when treating cervical dysplasia

Publish date: April 3, 2017

Cervical dysplasia is a condition commonly encountered by the gynecologist. It is either treated (with excision or ablation) or monitored, depending on the lesion grade, cytologic history, medical history, and reproductive goals. Cervical dysplasia commonly arises in women of reproductive age. Therefore, consider reproductive effects when deciding whether to treat or monitor, as well as when choosing the treatment modality.

Background

Approximately two-thirds of human papillomavirus infections resolve within a year, and more than 90% resolve within 2 years. Similarly, low-grade cervical intraepithelial neoplasia (CIN 1) lesions frequently resolve. High-grade (CIN 2 and CIN 3) lesions regress less commonly, with 5% and 12%-40% progressing to invasive cancer, respectively. Therefore, treatment is typically recommended.

Dr. Lindsay Robbins

Treatment methods include excision and ablation. Excision methods include cold knife conization (CKC), loop electrosurgical excision procedure (LEEP), or laser. Ablation typically involves cryotherapy or laser. Both methods have similar efficacy.¹

Obstetric implications

Potential obstetric risks of treatment for CIN include infertility, spontaneous abortion, preterm premature rupture of membranes (PPROM), preterm delivery, and perinatal/neonatal mortality. These risks are discussed individually below. Mechanisms that have been suggested for such complications include decreased cervical mucous, cervical scarring impeding conception or dilation, loss of cervical volume, collagen breakdown, and immunologic processes due to decreased physical defenses or microbiome shifts.

Fertility

Studies have shown that treatment does not appear to impede conception. The overall pregnancy rate is higher among treated women than untreated women. Pregnancy rates are not different among women intending to conceive or among women attempting conception for more than 12 months, with the caveat being that these studies are heterogenous.^2,3

Miscarriage

No difference has been observed in total (less than 24 weeks) miscarriage rate or first trimester (less than 12 weeks) miscarriage rate among treated and untreated women. However, the second trimester miscarriage rate is significantly higher among treated women (risk ratio, 2.60).² This risk is most notable following laser conization or LEEP.⁴ There may also be an association between ablation and pregnancy loss.

Preterm birth and PPROM

Several studies and meta-analyses show an association between preterm birth and treatment for CIN using LEEP or CKC. There is an increased risk of severe preterm delivery (relative risk, 2.78), extreme preterm delivery (relative risk, 5.33), and low birth weight (relative risk, 2.86) with CKC.⁵ LEEP is associated with the same outcomes, albeit the risk is lower than with CKC.⁶ The risk of preterm birth is even lower for ablation.⁷

Dr. Emma Rossi

This increased risk of preterm birth does not appear to depend on the presence of short cervix during pregnancy, yet increasing specimen size is associated with increasing obstetric complications. A repeat excisional procedure is associated with a nearly threefold increase in preterm labor (odds ratio, 2.8).⁸

The risk of PPROM is approximately two times higher among those treated with LEEP, and PPROM rates are higher among those treated with CKC, compared with LEEP.^9,10

Other complications

Ectopic pregnancy and termination rates may be higher in treated women, compared with untreated women.² However, there does not appear to be an increased risk for perinatal/neonatal mortality, cesarean section, or neonatal intensive care unit admission among women treated with excisional procedures.⁶

Pointers for practice

Due to the potential for adverse obstetric complications following excisional procedures for cervical dysplasia, gynecologists should closely adhere to the American Society for Colposcopy and Cervical Pathology guidelines when determining the appropriateness of dysplasia interventions. The decision to treat, versus monitor, dysplasia in a woman who plans future childbearing should be made with the patient after thorough discussion of the risks and benefits of each path.
Women younger than age 30 years should not be screened for high-risk human papillomavirus because of both its high incidence and its high rate of spontaneous resolution.
For reproductive-aged women with CIN 2 and adequate colposcopy, the American Society for Colposcopy and Cervical Pathology supports either monitoring with cytology and colposcopy every 6 months for a year or excisional treatment. However, women with CIN 3, inadequate colposcopy, prior cervical cancer, diethylstilbestrol exposure, or decreased immunity should undergo excisional treatment.
When selecting an excisional method (LEEP or CKC), surgeons should choose the most appropriate technique for the patient’s pathology but should acknowledge the observed higher rates of PPROM, preterm birth, and low-birth-weight infants among those receiving CKC, and tailor the size of the excision to the specific lesion.
Consider recommending a 12-month interval between treatment and pregnancy to ensure resolution of high-grade dysplasia. Furthermore, obstetric risk may be increased within 12 months following treatment.

Dr. Robbins is a resident in the department of obstetrics and gynecology at the University of North Carolina, Chapel Hill. Dr. Rossi is an assistant professor in the division of gynecologic oncology at UNC, Chapel Hill. They reported having no relevant financial disclosures.