Reproductive choices and outcomes after freezing oocytes for medical reasons: a follow-up study.Hum Reprod. 2014 Sep; 29(9):1925-30.HR
What reproductive choices do women make after they have cryopreserved oocytes for medical reasons?
Women who had cryopreserved oocytes for medical reasons and tried to become pregnant, either attempted natural conception or resorted to assisted reproduction with fresh oocytes.
WHAT IS KNOWN ALREADY
Women confronted with a risk of premature ovarian insufficiency, due to gonadotoxic therapy, ovarian surgery or genetic predisposition, have an indication to cryopreserve oocytes. Many of these women will retain ovarian function, thus will retain the possibility of natural conception. The added value of cryopreserved oocytes to reproductive outcomes is unknown as there is a lack of follow-up of women who have cryopreserved oocytes for medical reasons.
STUDY DESIGN, SIZE AND DURATION
This follow-up study included a cohort of 85 women who cryopreserved their oocytes for medical reasons between 2009 and 2012.
PARTICIPANTS/MATERIALS, SETTING AND METHODS
Medical data from women who cryopreserved their oocytes at the Centre for Reproductive Medicine in the Academic Medical Centre in Amsterdam were extracted and self-report questionnaires were disseminated. The collected data considered demographics, outcomes of ovarian stimulation, fertility-threatening treatments, menstrual cycle changes, pregnancy attempts and outcomes and intended plans for the cryopreserved oocytes.
MAIN RESULTS AND THE ROLE OF CHANCE
A total of 68 women, followed up for an average 25.3 months, returned the questionnaire (response rate: 80%). None of the women had used her cryopreserved oocytes although 16 women had tried to conceive. Of these women, eight were trying to conceive naturally, five had conceived naturally within 2 months and three had conceived with assisted reproduction not requiring cryopreserved oocytes (two women with conventional IVF because of tubal pathology and endometriosis and one woman with IUI because of polycystic ovary syndrome). Three out of the eight pregnancies had resulted in live births, two resulted in miscarriages and three were ongoing. Most women (71%) intended to conceive with their cryopreserved oocytes as a last resource option.
LIMITATIONS, REASONS FOR CAUTION
Transferability of our findings is challenged by the small sample but positively affected by our high response rate. As the time span between cryopreservation of oocytes and follow-up was short, follow-up of the cohort should be repeated in 2 years.
WIDER IMPLICATIONS OF THE FINDINGS
After a mean follow-up of 2 years, none of the women with a medical reason to cryopreserve oocytes had used her oocytes. Women who were trying to conceive during follow-up were doing so without using their stored oocytes. It is unclear whether starting assisted reproduction while having cryopreserved oocytes is the most appropriate clinical decision. Our findings emphasize the relevance of taking the chances of natural conception into account in counselling women about cryopreservation of oocytes.
STUDY FUNDING/COMPETING INTERESTS
This study was not externally funded. There are no conflicts of interest to declare.