A New Approach to Selected Sperm Injection - Results from a Prospective, Comparative Cohort

Objective: To define indications for employing high magnification (HM) in sperm selection procedures during intracytoplasmic sperm injection (ICSI).

Methods: Prospective cohort study comparing selected sperm injection (sICSI) and conventional ICSI in a single assisted reproductive technology unit. Couples, presenting infertility and an indication for an ART intervention were included. sICSI was performed after an ICSI cycle resulting in <50% fertilizations, no embryo transfer or sperm head abnormalities (score 0) at high magnification were >40%. Main outcome measures were pregnancy and birth rates.

Results: 3339 ICSI cycles (37.1%) and 5673 sICSI cycles (62.9%) were included. sICSI cycles were more likely to end in a pregnancy (OR 1.173, P=.009) after correction for age, body-mass index (BMI), number of past treatments and anti mullerian hormone (AMH) level. In terms of live births, ICSI and sICSI were alike. When the cohort was split according to total motile sperm count (TMC) categories, the sICSI method was significantly better in the severe oligozoospermia range (TMC≤1 million) with female partner’s age range of 30-40 years :chance for a pregnancy increased by about 70% (OR 1.68, 95% CI 1.19-2.35) and two-fold for live birth (OR 2.05, 95% CI 1.36-3.08) in favour of sperm selection. With severe oligozoospermia, the miscarriage rate was also significantly lower.

Conclusions: Spermatozoa selection using a high magnification sperm scoring system provides better outcomes for certain populations. We propose that sICSI should be considered as a first line procedure for severe male factor circumstances and as a second line in cases of ICSI blastulation failure.