From the Guidelines
Tubal ligation does reduce the risk of ovarian cancer, with factors associated with a reduced risk including the use of oral contraceptives, pregnancy and breastfeeding, bilateral tubal ligation, and removal of the ovaries, as stated in the studies 1. The protective effect of tubal ligation on ovarian cancer risk is thought to occur because the procedure blocks the fallopian tubes, preventing potential carcinogens from the external environment from traveling up through the reproductive tract to the ovaries.
- The surgery also reduces the amount of blood flow to the ovaries, which may decrease hormone stimulation that could otherwise promote cancer development.
- The cancer-protective benefit appears to be greatest for endometrioid and clear cell ovarian cancers, though some protection extends to other types as well.
- This risk reduction is long-lasting and typically persists for decades after the procedure. However, tubal ligation does not appear to significantly reduce the risk of other reproductive cancers such as breast, endometrial, or cervical cancer. It's essential to consider this cancer reduction benefit as an additional advantage rather than the primary reason for choosing tubal ligation, which is permanent contraception, as noted in the studies 1. The exact percentage of risk reduction is not explicitly stated in the provided studies, but the association between tubal ligation and reduced ovarian cancer risk is consistently mentioned across the studies 1.
From the Research
Tubal Ligation and Cancer Risk Reduction
- Tubal ligation has been associated with a decreased risk of invasive epithelial ovarian cancer, with studies suggesting a risk reduction of around 34% 2.
- A case-control study found that tubal ligation reduced the risk of ovarian cancer in women with BRCA1 mutations, with an odds ratio of 0.39 3.
- Another study found that tubal ligation reduced the overall risk of epithelial ovarian cancer by 13% (odds ratio 0.87), with significant risk reductions associated with endometrioid cancer (odds ratio 0.66) and epithelial ovarian cancer of "other" histology (odds ratio 0.60) 4.
- Bilateral salpingectomy was also found to reduce the risk of epithelial ovarian cancer by 42% (odds ratio 0.58) 4.
Mechanisms of Cancer Risk Reduction
- The underlying mechanisms of ovarian cancer risk reduction after tubal ligation are not fully understood, but may include a mechanical barrier against ascending carcinogenic agents and prevention of endometrial and proximal Fallopian tube cell ascent 5.
- Tubal ligation may also alter ovarian function and prevent the retrograde transport of carcinogenic substances from the vagina 5.