Haematological malignancies and fertility
1. GENERAL CONCEPTS
● The term "fertility" is used to describe the capacity to have children. Some cancer treatments affect the fertility both in men and women.
● Depending on the type and intensity of the treatment the ovaric function can be strongly or slightly affected.
● Although the majority of the patients that have overcome a neoplasia are able to conceive, get pregnant normally and have healthy babies, a significant percentage may have irreversible ovarian damage (for more information please refer to the paper of Dr. Manau).
● The level of ovarian damage caused by chemotherapy will increase with the age of the patient (the older the patient the more severe the gonad damage).
● Damage in the ovaries caused by chemotherapy has two main consequences for fertile women. First of all, it causes a premature menopause (unnatural paralysation of the ovaric function) and, as a consequence, infertility. This premature ovaric deficiency is commonly treated with hormone substitution therapy. A healthy diet and regular exercise should be added to this therapy to diminish the health risks associated to menopause, such as osteoporosis.
● Ovaric damage can appear as amenorrhea (absence of menstruation) or as an alteration of the menstrual cycle rhythm, but it should be known that the presence of menstruation does not guarantee a good ovaric function. They may exist hidden ovaric faults, and if this occurs women can have menstruation, but remain infertile.
● Post-treatment infertility does NOT always happen. With the same treatment, some patients may develop it or not. Again, age is a critical factor here. Infertility is NOT always permanent and can be reversed, especially in younger patients.
● It is essential that, before starting a chemotherapy treatment, fertile women talk about this matter with their haematologist, because in some cases some measures could be taken to preserve the capacity to give birth.
● Some drugs used to treat cancer, such as Imatinib, do not harm the ovary, but can be toxic to the fetus. Therefore, some contraceptive measures during the administration of these drugs should be taken. You should also ask your oncologist immediately in case you think you might be pregnant.
● However, and despite the information above, the great majority of the children from people that have suffered cancer are completely healthy. The amount of babies with birth defects born from people that have suffered cancer is similar to those born from people who haven´t suffered it. Having cancer does not mean that your kids have the risk of having it. Very few cancer cases are hereditary.
2. OPTIONS TO PRESERVE FERTILITY
2.1. Before receiving the treatment:
There are only two procedures with proven efficiency to preserve fertility: embryonic cryopreservation and two surgical techniques, tracheolectomy (for some cervix cancers) and ovary transposition, for patients that have to receive pelvix radiotherapy.
• Embryo freezing. Mature ovules are extracted and fertilized with spermatozoids from the partner of the patient or from a donor. Afterwards, these ovules are frozen and stored. The surviving embryo percentage after defrosting is between 40-90% and the percentage of success in the implantation on the patient is between 25-30%. Therefore, this is the option with highest probabilities of success. However, the collection of ovules requires of an ovaric stimulation using hormones that last about two weeks and is usually started on the first days of menstruation. Therefore, this can mean a delay of 4 to 5 weeks in the beginning of the treatment. This might not be a problem in some neoplasia cases but it definitely is in patients with severe haematological malignancies because in these cases the treatment should start immediately. This treatment is also contraindicated in patients with hormone-dependant neoplasia. Finally, this treatment has always caused ethical debates because of cryopreservation of embryos that may not be used.
There are also some other treatments that are still in the experimental phase:
• Ovaric tissue freezing I. Part or the entire ovary is extracted and frozen for future use. This technique initially had serious difficulties in freezing the tissue. However, in recent years, the introduction of new freezing and ovule fecundation techniques has notably improved the implantation and gestation rates. This technique also requires an ovaric stimulation that lasts two weeks, thus delaying the start of the treatment.
• Ovaric tissue freezing II. This technique is still incipient, and has only been used in a few pregnant women. It is based on obtaining a piece of ovary, using laparoscopic techniques, and freezing it. Once the malignant tumour is removed, it is possible to implant the ovaric tissue, either in the ovaric area, or even intramuscularly or subcutaneously. The ovaric tissue function is recovered in a few weeks and it is possible to gestate spontaneously or by vitro fecundation. This technique does not require a wait for the ovaric stimulation as with the other two. However, it is possible that the ovaric tissue collected could have micrometastasis from the tumour that, in theory, could be reintroduced in the organism when it is implanted.
2.2 During the treatment:
• Gonadotropine releasing hormones (GnRHs). These drugs may have a protective effect over the ovary if they are administered during chemotherapy. However the mechanisms of actuation are still unknown and its efficiency has not been proven in controlled studies. Furthermore they are not effective in very intense chemotherapy treatments.
2.3. Other options following treatment if a person cannot conceive:
● Embryos from a donor. This option allows a woman to become pregnant with a donated embryo.
● Ovules from a donor. A woman can receive ovules donated that have been previously fertilized with her partner's semen.
● It should not be forgotten that adoption is an excellent option for couples in this situation. In general, patients that have received treatment against cancer and that no longer have a tumour fulfil all the requisites for adoption, although the policies may vary from one country to another, making it important to have some previous information.
This section is merely informative and is very general, so please talk with your haematologist about the specific effects that each treatment may have on your fertility.
Ask your haematologist about your state and the possibilities that you have.
For more information:
- Paper "Fertility after cancer", from MD Anderson Cancer Institute
- Online consultation with Dr. Carreras, medical director of the José Carreras Foundation.
- Read the testimonies of other patients and ex-patients of leukaemia and other haematological malignancies.