Page 26 - Aspire April -2023 Vol 8 / Issue 2

REPRODUCTIVE ENDOCRINOLOGY SIG (includes PCOS)
Key focus on ovulation induction protocols for fertility preservation
in cancer patients
By Dr Madhuri Patil
Referral of cancer patients for counselling on fertility preservation and the incidence of patients undergoing treatment has increased due to improved survival rates in these patients.
For fertility preservation, where oocyte and embryo cryopreservation is planned, ovulation induction is necessary. We need different protocols in cancer patients such as:
• urgency of starting treatment;
• short protocol to reduce delay of starting chemo/radiotherapy; and
• minimising risk of OHSS while at the same time generating enough oocytes.
One has to avoid high E2 exposure in breast cancer oestrogen receptor (ER) and progesterone receptor (PR) positive cancers.
There is also the age factor. For pubertal and girls <18 there might be difficulty in deciding on the dose of gonadotrophins (GT) as AMH and/or AFC may be misleading, and there could be problems with monitoring techniques.
It is important that we counsel and reassure patients after explaining in detail the procedures and risks involved.
Informed consent, especially regarding posthumous use of gametes and embryos, is essential.
Parental consent is also essential for pre-pubertal and adolescents girls. So too is pre-anaesthetic work-up and clearance (blood biochemistry, X-ray, ECG, viral markers).
Pre-procedure assessment of ovarian reserve by measuring AMH and AFC is necessary. Ovarian reserve may be less due to poor general health, increased catabolic state, malnutrition, stress and impairment of granulosa cell function.
Ovarian reserve can also be affected if the patient has been subjected to chemotherapy before fertility preservation.
General principles of OI in cancer patients:
• use GnRH antagonist protocol either fixed or flexible protocol;
Madhuri Patil (India)
• use gonadotropin dose depending on age, BMI and ovarian reserve;
• trigger with GnRH agonist 36 hrs before oocyte retrieval;
• in estrogen receptor positive breast cancer patients add letrozole 5 mg/day or tamoxifen 20mg to reduce estrogen concentrations;
• one could stimulate the patient in early/mid follicular phase, late follicular phase (7 days after MC with emergence of dominant follicle (>13 mm) or luteal phase (progesterone level >3 ng/m); and
• feasibility of random start ovulation induction protocols is based on multiple waves of follicle recruitment during a normal menstrual cycle.
Random start protocol is an option when urgent fertility preservation is desired and provides significant advantage by decreasing total time for the IVF cycle without compromising oocyte yield and maturity and embryo quality.
In conclusion, there is no definite evidence for reduced ovarian reserve in cancer patients. Fertility preservation with ovulation induction for oocyte or embryo cryopreservation is a feasible and safe option in cancer patients.
It is necessary to maintain a balance between heavy stimulation to get maximum yield for cryopreservation against the risk of OHSS.
COS with fertilility preservation should be done preferably before initiating chemotherapy or else less oocytes are retrieved with increased mutagenesis.
24