In vitro fertilization (IVF) with embryo cryopreservation is seen as a strong option for preserving the potential to have a child; however, there is concern that ovarian stimulation in IVF could cause proliferation of breast cancer cells, leading some practitioners to recommend natural cycle (nonstimulated) IVF.
It is not clear whether ovarian suppression during cancer treatment preserves fertility, according to the guideline. Tamoxifen as an ovarian stimulant has been investigated and has shown promise in treating women whose fertility has been compromised as a result of breast cancer treatment. Although the aromatase inhibitor letrozole cannot be used in premenopausal women as a breast cancer treatment, it may be used in combination with gonadotropins as a fertility agent following treatment.
Finally, routine endometrial biopsy and uterine ultrasonography are not recommended for postmenopausal women taking tamoxifen without evidence of vaginal bleeding, as ultrasound has been associated with a significant false-positive rate leading to unnecessary invasive diagnostic procedures.
However, for women on tamoxifen who experience vaginal bleeding, an endometrial evaluation – including biopsy and follow-up of possible uterine structural anomalies – is essential, the guideline states.
The members of the Committee on Practice Bulletins–Gynecology who wrote the guideline reported no relevant conflicts of interest.