Pregnancy Outcome Following Treatment of Premalignant Lesion of the Cervix in Southeast Nigeria; A Retrospective Case-Control Study

Treatment of cervical pre-cancers involves ablative and excisional therapies, and these have the potential to affect future pregnancy outcomes of women. Understanding the impact of the various treatment modalities on the outcome of pregnancies can motivate the development of interventions to improve pregnancy outcomes in women who had cervical pre-cancer treatment. We aimed to the effect of cervical pre-cancer treatment on second-trimester miscarriages and preterm births. Matched case-control study in which 373 women who had a pregnancy after cervical pre-cancer treatment were matched with 373 controls. McNemar Chi-square was used to compare the prevalence of second-trimester miscarriage and preterm birth between the study group and the matched controls. Conditional logistic regression analysis was done to determine the risk factors for second-trimester miscarriage and preterm birth. Second-trimester miscarriages and preterm births were higher in women who had cervical pre-cancer treatment (AOR: 2.05, 95% CI: 1.174 - 3.693, p: 0.01) and (AOR: 2.74, 95% CI: 1.591 - 4.902, p: 0.0001) respectively. In addition, large loop excision of the transformation zone (LLETZ) of the cervix increased the odds of second-trimester miscarriage (AOR: 1.22, 95% CI: 1.034 - 1.441, p: 0.019) and preterm birth (AOR: 2.98, 95% CI: 1.793 - 3.965, p: 0.001). Cryotherapy and thermocoagulation were not associated with increased miscarriage and preterm birth. Treatment to pregnancy interval of ≥ 12 months decreased the odds of second-trimester miscarriage (AOR: 0.605, 95% CI: 0.502 - 0.808, p: 0.031) and preterm birth (AOR: 0.484, 95% CI: 0.317 - 0.738, p: 0.001). There is an increased odds of second-trimester miscarriage and preterm birth in women treated with LLETZ. A treatment-to-pregnancy interval of ≥ 12 months reduces this odd. Ablative therapies do not increase the odds of miscarriages and preterm births. This information could guide decisions on the choice of method of treatment for cervical pre-cancer in women of childbearing age.