Does age of the sperm donor influence live birth outcome in assisted reproduction?

ABSTRACT

STUDY QUESTION Does age of the sperm donor have an effect on reproductive outcomes (live birth rate and miscarriage occurrence) of donor insemination or in vitro fertilization treatment using donated sperm? SUMMARY ANSWER Live birth and miscarriage occurrence in assisted reproduction treatment using donor sperms was not found to be affected by the age of sperm donors up to 45 years old. WHAT IS ALREADY KNOWN Literature on the effect of sperm donor age on outcome of medically assisted reproduction is scarce. Most researchers agree that semen parameters deteriorate with increasing paternal age. However, there is no substantial evidence to suggest that this deterioration adversely affects the reproductive outcomes in couples undergoing medically assisted reproduction. STUDY DESIGN, SIZE, DURATION This retrospective cohort study analysed 46 078 first donor insemination treatments and fresh in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles using donated sperm from 1991 to 2012. PARTICIPANTS/ DURATION/METHODS: The first fresh donor insemination and IVF/ICSI treatment cycles (46 078 treatment cycles) using donated sperm from the long-term anonymized data registry from 1991 to 2012 of the HFEA, the UK regulator, were analysed by the binary logistic modelling technique for association between sperm donor age and reproductive outcomes (live birth occurrence and miscarriage occurrence). The statistical package SPSS (version 21) was used for analysis and results were considered to be statistically significant if the P-value was <0.05. MAIN RESULTS AND THE ROLE OF CHANCE Of 46 078 women, 84.6% (N = 38 974) underwent donor insemination treatment and the remainder, 15.4% (N = 7104), had IVF/ICSI treatment with donor sperm. The live birth occurrence decreased with increasing female age in both treatment groups; In the donor insemination treatment group, it was 11.1% in 18-34 year old women, 8.3% in 35-37 year old women and 4.7% in 38-50 year old women. The corresponding figures in the IVF/ICSI treatment group were 28.9, 22.0 and 12.9% respectively. In each of these subgroups, no evidence of declining likelihood of live birth with increasing sperm donor age was found (P > 0.05). The miscarriage occurrence (i.e. number of miscarriages per 100 women commencing treatment) was 1.3% in 18-34 year old women, 1.9% in 35-37 year old women and 1.9% in 38-50 year old women undergoing donor insemination treatment. In the sperm donation IVF/ICSI treatment group, these figures were 5.7, 8.4 and 6.8% respectively. The results were not suggestive of any unfavourable effect of advancing sperm donor age on the odds of miscarriage occurrence (P > 0.05). LIMITATIONS, REASONS FOR CAUTION As sperm donors are a select population based on good semen indices, the generalization of results to the paternal population at large may not be possible. Although the study subgroups were controlled for female age, treatment modality and effect of previous treatment cycles, adjustments for certain potential compounding factors, such as smoking status, BMI of women and stimulation protocol used in IVF/ICSI treatment cycles, were not possible. WIDER IMPLICATIONS OF THE FINDINGS: Live birth and miscarriage occurrence following assisted reproduction weren't adversely affected by increasing sperm donor age up to 45 years. In view of the increasing demand for donor sperm, further studies may be required to ascertain the safe upper age limit for sperm donors. STUDY FUNDING/COMPETING INTERESTS No funding was received from any individual or funding agency. NG was on a Commonwealth Scholarship for the duration of the study. The authors do not have any conflicts of interest to declare.