Assisted reproductive technology poses no ovarian cancer risk
Assisted reproductive technology (ART) does not promote the development of ovarian tumours, and the risk increase seen in ART-treated women is likely related to nulliparity instead, according to a study.
The study included 30,625 women who received ovarian stimulation for ART and 9,988 subfertile women not treated with ART. The mean number of ART cycles was 3.3, and more women in the ART group remained nulliparous (35.4 percent vs 25.2 percent). Follow-up duration was longer in the non-ART control group (25.7 vs 23.4 years), and so at end of follow-up, the group was older than the group of women who received ART (median age, 57.0 vs 55.9 years).
Over a median follow-up of 24 years, a total of 158 invasive and 100 borderline ovarian tumours occurred. Ovarian cancer risk was higher in the ART group than in the general population (standardized incidence ratio [SIR], 1.43, 95 percent confidence interval [CI], 1.18–1.71) but not significantly different relative to the non-ART group (adjusted hazard ratio [HR], 1.02, 95 percent CI, 0.70–1.50).
The risk was lower among women with higher parity and with a larger number of successful ART cycles (resulting in childbirth, ptrend=0.001). On the other hand, there was no association observed for the number of unsuccessful ART cycles.
Meanwhile, borderline ovarian tumour risk was elevated in the ART group compared with both the general population (SIR, 2.20, 95 percent CI, 1.66–2.86) and the non-ART group (HR, 1.84, 95 percent CI, 1.08–3.14). A higher number of ART cycles or longer follow-up time did not modify the risk.
More studies are needed to examine the role of ART in the aetiology of borderline ovarian tumours.