Oncofertility and fertility preservation

Overview

• Triple-negative breast cancer is more common under 40, and chemotherapy usually starts within weeks of diagnosis. Cancer Research UK says national guidelines expect the team to discuss fertility at diagnosis, that egg or embryo freezing takes about 2 to 3 weeks, that ovarian tissue freezing is available in a growing number of UK centres, and that NHS funding varies by area. Because this cancer has no hormone receptors, there is no endocrine therapy to interrupt afterwards; the question is protecting eggs before the first cycle.
• Bowel cancer: Bowel Cancer UK says some treatments affect fertility and the team should discuss the risk at diagnosis, that radiotherapy to the pelvis will often cause infertility and early menopause and will affect the uterus so that pregnancy is not possible even with fertility treatment, that chemotherapy can cause temporary or permanent infertility depending on the drugs and doses, and that both men and women should use contraception during radiotherapy and chemotherapy and for about a year afterwards.
• Breast cancer in the UK: NICE NG101 (1.1.5) sends fertility preservation to the NICE fertility guideline, now NG257 (2026). NG257 (1.53.1) says to discuss fertility preservation with people preparing for medical treatment likely to impair their fertility, and that for people who need urgent treatment this discussion should take place at the earliest possible opportunity; (1.53.5) to offer sperm cryopreservation and (1.53.6) oocyte or embryo cryopreservation to people of reproductive age; and (1.53.7) to consider ovarian tissue cryopreservation where those are not feasible.
• The funding sentence most people are never told: NG257 (1.53.3) says that for NHS-funded fertility preservation, do not apply the eligibility criteria used for conventional fertility treatment, including the lower age limit. NG257 (1.53.4) adds that those criteria will apply when it comes to using the stored material, and (1.53.8) that storage is reviewed at least every 5 years with continued NHS funding for people who remain at significant risk of infertility.
• Timing and the alternative. Cancer Research UK says egg collection and freezing takes about 2 to 3 weeks, that letrozole or tamoxifen can be combined with lower-dose IVF hormones, and that IVF is available for some people on the NHS but not in all parts of the country. Where there is no time, switching the ovaries off during chemotherapy is the other route: in an individual patient-level meta-analysis of 873 patients from five trials, premature ovarian insufficiency occurred in 14.1 percent given a GnRH agonist against 30.9 percent of controls (adjusted odds ratio 0.38) and post-treatment pregnancy in 10.3 against 5.5 percent, with no significant difference in disease-free or overall survival.
• Lymphoma: Lymphoma Action says fertility preservation is generally more effective when begun before treatment, that sperm must be banked beforehand, and that egg freezing and embryo storage involve about two weeks of daily injections before the eggs are collected. It quotes NICE as saying there should be no lower age limit on who is offered preservation, that it may be available up to age 40 and that this varies across the NHS, and that the impact on fertility should be discussed at diagnosis. Because aggressive lymphoma is often treated within days, the number of days available before treatment must start is the question the decision turns on.