Neighborhood deprivation in relation to ovarian reserve and outcomes of ovarian stimulation among oocyte donors.

OBJECTIVE: To study the relationship between neighborhood deprivation index (NDI) and markers of ovarian reserve and outcomes of controlled ovarian stimulation among young, healthy oocyte donors. DESIGN: Retrospective cohort study. PATIENTS: A total of 547 oocyte donors who underwent 905 oocyte retrieval cycles (2008-2020) at a private fertility center in Sandy Springs, Georgia, United States. INTERVENTIONS: Neighborhood deprivation index was calculated using principal component analysis applied to census-level measures of poverty, employment, household composition, and public assistance, which was then standardized and linked to donor information on the basis of donor residence. MAIN OUTCOME MEASURES: Markers of ovarian reserve, including antral follicle count (AFC) and antimüllerian hormone (AMH) levels, and outcomes of controlled ovarian stimulation including number of total and mature oocytes retrieved and ovarian sensitivity index (OSI) (defined as the number of oocytes retrieved/total gonadotropin dose × 1,000). Multivariable generalized estimating equations with Poisson and normal distribution were used to model the relationship between NDI and outcome measures adjusting for age, body mass index, and year of retrieval. RESULTS: The mean (SD) age of donors was 25.0 (2.8) years and 29% of the donors were racial or ethnic minorities. There were no associations between donor NDI and ovarian reserve markers. For every interquartile range increase in NDI, there was a reduction of -1.5% (95% confidence interval: -5.3% to 2.4%) in total oocytes retrieved although the effect estimate was imprecise. Associations of NDI with a number of mature oocytes retrieved and OSI were in a similar direction. We observed evidence for effect modification of the NDI and OSI association by donor race. There was a suggestive positive association between NDI and OSI in Black donors but no association in White donors. CONCLUSION: In this cohort of young, healthy, racially diverse oocyte donors, we found little evidence of associations between NDI and markers of ovarian reserve or outcomes of ovarian stimulation.

Ambient traffic related air pollution in relation to ovarian reserve and oocyte quality in young, healthy oocyte donors.

Studies in mice and older, subfertile women have found that air pollution exposure may compromise female reproduction. Our objective was to evaluate the effects of air pollution on ovarian reserve and outcomes of ovarian stimulation among young, healthy females. We included 472 oocyte donors who underwent 781 ovarian stimulation cycles at a fertility clinic in Atlanta, Georgia, USA (2008-2019). Antral follicle count (AFC) was assessed with transvaginal ultrasonography and total and mature oocyte count was assessed following oocyte retrieval. Ovarian sensitivity index (OSI) was calculated as the total number of oocytes divided by total gonadotrophin dose × 1000. Daily ambient exposure to nitric oxide (NOx), carbon monoxide (CO), and particulate matter ≤ 2.5 (PM2.5) was estimated using a fused regional + line-source model for near-surface releases at a 250 m resolution based on residential address. Generalized estimating equations were used to evaluate the associations of an interquartile range (IQR) increase in pollutant exposure with outcomes adjusted for donor characteristics, census-level poverty, and meteorological factors. The median (IQR) age among oocyte donors was 25.0 (5.0) years, and 31% of the donors were racial/ethnic minorities. The median (IQR) exposure to NOx, CO, and PM2.5 in the 3 months prior to stimulation was 37.7 (32.0) ppb, 612 (317) ppb, and 9.8 (2.9) µg/m3, respectively. Ambient air pollution exposure in the 3 months before AFC was not associated with AFC. An IQR increase in PM2.5 in the 3 months before AFC and during stimulation was associated with -7.5% (95% CI -14.1, -0.4) and -6.4% (95% CI -11.0, -1.6) fewer mature oocytes, and a -1.9 (95% CI -3.2, -0.5) and -1.0 (95% CI -1.8, -0.2) lower OSI, respectively. Our results suggest that lowering the current 24-h PM2.5 standard in the US to 25 µg/m3 may still not adequately protect against the reprotoxic effects of short-term PM2.5 exposure.

The effects of oocyte donor and recipient body mass index on live birth rates and pregnancy outcomes following assisted reproduction.

OBJECTIVE: To investigate the effects of oocyte donor and recipient body mass index (BMI) on outcomes of vitrified donor oocyte assisted reproductive technology (ART). DESIGN: Retrospective cohort study. SETTING: Private fertility center. PATIENTS: A total of 338 oocyte donors and 932 recipients who underwent 1,651 embryo transfer cycles in 2008-2015. INTERVENTIONS: Multivariable log binomial regression models with cluster-weighted generalized estimating equations were used to estimate the adjusted risk ratios. MAIN OUTCOME MEASURES: Live birth, defined as the delivery of at least one live-born infant, including all embryo transfer cycles. Secondary outcomes included birth weight and gestational length only among singleton live births. RESULTS: The mean ± SD body mass indexes (BMIs) of donors and recipients were 22.6 ± 2.5 kg/m2 and 24.6 ± 4.8 kg/m2, respectively. There were no significant associations between donor BMI and probability of live birth. Recipients with BMI ≥35 kg/m2 had a significantly higher probability of live birth compared with normal-weight recipients. Among singleton live births, recipients with BMI <18.5 kg/m2 had a lower risk whereas women with BMI ≥35 kg/m2 had a higher risk of delivery in an earlier gestational week compared with normal weight women. Recipients with a BMI ≥35 kg/m2 also had a higher risk of having a low birth weight infant compared with normal-weight women. CONCLUSIONS: In the setting of vitrified donor oocyte ART, recipient BMI was positively associated with probability of live birth but negatively associated with gestational length and birth weight among singleton births.

The effect of donor and recipient race on outcomes of assisted reproduction.

BACKGROUND: A growing literature suggests that minority races, particularly Black women, have a lower probability of live birth and higher risk of perinatal complications after autologous assisted reproductive technology. However, questions still remain as to whether these racial disparities have arisen because of associations between race and oocyte/embryo quality, the uterine environment, or a combination of the two. Oocyte donation assisted reproductive technology represents a unique approach to examine this question. OBJECTIVE: This study aimed to evaluate the associations between the race of female oocyte donors and recipients and live birth rates following vitrified donor oocyte assisted reproductive technologies. STUDY DESIGN: This was a retrospective study conducted at a single, private fertility clinic that included 327 oocyte donors and 899 recipients who underwent 1601 embryo transfer cycles (2008-2015). Self-reported race of the donor and recipient were abstracted from medical records. Live birth was defined as the delivery of at least 1 live-born neonate. We used multivariable cluster weighted generalized estimating equations with binomial distribution and log link function to estimate the adjusted risk ratios of live birth, adjusting for donor age and body mass index, recipient age and body mass index, tubal and uterine factor infertility, and year of oocyte retrieval. RESULTS: The racial profile of our donors and recipients were similar: 73% white, 13% Black, 4% Hispanic, 8% Asian, and 2% other. Women who received oocytes from Hispanic donors had a significantly higher probability of live birth (adjusted risk ratio, 1.20; 95% confidence interval, 1.05-1.36) than women who received oocytes from white donors. Among Hispanic recipients, however, there was no significant difference in probability of live birth compared with white recipients (adjusted risk ratio, 1.07; 95% confidence interval, 0.90-1.26). Embryo transfer cycles using oocytes from Black donors (adjusted risk ratio, 0.86; 95% confidence interval, 0.72-1.03) and Black recipients (adjusted risk ratio, 0.84; 95% confidence interval, 0.71-0.99) had a lower probability of live birth than white donors and white recipients, respectively. There were no significant differences in the probability of live birth among Hispanic, Asian, and other race recipients compared with white recipients. CONCLUSION: Black female recipients had a lower probability of live birth following assisted reproductive technology, even when using vitrified oocytes from healthy donors. Female recipients who used vitrified oocytes from Hispanic donors had a higher probability of live birth regardless of their own race.

Laboratory processing and intracytoplasmic sperm injection using epididymal and testicular spermatozoa: what can be done to improve outcomes?

There are two main reasons why sperm may be absent from semen. Obstructive azoospermia is the result of a blockage in the male reproductive tract; in this case, sperm are produced in the testicle but are trapped in the epididymis. Non-obstructive azoospermia is the result of severely impaired or non-existent sperm production. There are three different sperm-harvesting procedures that obstructive azoospermic males can undergo, namely MESA (microsurgical epididymal sperm aspiration), PESA (percutaneous epididymal sperm aspiration), and TESA (testicular sperm aspiration). These three procedures are performed by fine-gauge needle aspiration of epididymal fluid that is examined by an embryologist. Additionally, one technique, called TESE (testicular sperm extraction), is offered for males with non-obstructive azoospermia. In this procedure, a urologist extracts a piece of tissue from the testis. Then, an embryologist minces the tissue and uses a microscope to locate sperm. Finding sperm in the testicular tissue can be a laborious 2- to 3-hour process depending on the degree of sperm production and the etiology of testicular failure. Sperm are freed from within the seminiferous tubules and then dissected from the surrounding testicular tissue. It is specifically these situations that require advanced reproductive techniques, such as ICSI, to establish a pregnancy. This review describes eight different lab processing techniques that an embryologist can use to harvest sperm. Additionally, sperm cryopreservation, which allows patients to undergo multiple ICSI cycles without the need for additional surgeries, will also be discussed.

Laboratory processing and intracytoplasmic sperm injection using epididymal and testicular spermatozoa: what can be done to improve outcomes?

There are two main reasons why sperm may be absent from semen. Obstructive azoospermia is the result of a blockage in the male reproductive tract; in this case, sperm are produced in the testicle but are trapped in the epididymis. Non-obstructive azoospermia is the result of severely impaired or non-existent sperm production. There are three different sperm-harvesting procedures that obstructive azoospermic males can undergo, namely MESA (microsurgical epididymal sperm aspiration), PESA (percutaneous epididymal sperm aspiration), and TESA (testicular sperm aspiration). These three procedures are performed by fine-gauge needle aspiration of epididymal fluid that is examined by an embryologist. Additionally, one technique, called TESE (testicular sperm extraction), is offered for males with non-obstructive azoospermia. In this procedure, a urologist extracts a piece of tissue from the testis. Then, an embryologist minces the tissue and uses a microscope to locate sperm. Finding sperm in the testicular tissue can be a laborious 2- to 3-hour process depending on the degree of sperm production and the etiology of testicular failure. Sperm are freed from within the seminiferous tubules and then dissected from the surrounding testicular tissue. It is specifically these situations that require advanced reproductive techniques, such as ICSI, to establish a pregnancy. This review describes eight different lab processing techniques that an embryologist can use to harvest sperm. Additionally, sperm cryopreservation, which allows patients to undergo multiple ICSI cycles without the need for additional surgeries, will also be discussed.

Clinical evaluation of the efficiency of an oocyte donation program using egg cryo-banking.

OBJECTIVE: To evaluate the efficiency of oocyte donation cycles using egg "cryo-banking." DESIGN: Study conditions for vitrified/warmed oocytes for 20 non-autologous recipients (from 10 donors) were set prospectively, and outcomes of it were later compared retrospectively to nine fresh donations cycles. SETTING: Private assisted reproductive technology program. PATIENT(S): Ten donors and 20 infertile recipients. INTERVENTION(S): Oocytes were vitrified 3 to 4 hours after collection and cryo-stored. Intracytoplasmic sperm injection was performed 3 hours after warming, and embryos were in vitro cultured for 5 days. Two or three blastocysts were transferred per patient. MAIN OUTCOME MEASURE(S): Oocyte survival, fertilization, development, clinical pregnancy, and implantation rates. RESULT(S): A total of 153 oocytes were warmed and 134 survived. A total of 117 fertilized and 68% developed to blastocyst stage. A total of 47 embryos were transferred (2.35 embryos per recipient) and 26 implanted. Fifteen patients achieved ongoing pregnancies initially, and two additional pregnancies were obtained after transfer of supernumerary vitrified/warmed embryos. Nine of the 10 donors from the current study had previous fresh donations cycles from where seven clinical pregnancies were established in nine recipients, providing the base for comparison. CONCLUSION(S): Oocyte donation using vitrified/warmed oocytes can provide high pregnancy and implantation rates, and thus can be considered as efficient treatment procedure with additional benefits to recipients.

Comparison of ICSI and conventional IVF in patients with increased oocyte immaturity.

Using sibling oocytes, the objective of this study was to compare the intracytoplasmic sperm injection (ICSI) fertilization rates to those achieved with conventional IVF in patients with high rates of oocyte immaturity. This study was observational in nature, and included 91 patients who were treated using split insemination techniques. The fertilization rates for the ICSI group and the IVF group were 41.1 +/- 15.0% and 53.2 +/- 19.8%, respectively (P <: 0.0001). There was no significant difference in day-3 embryo quality between the two groups. There was a significantly higher number of embryos frozen in the IVF group than in the ICSI group: 357 (84.8%) and 297 (76.7%), respectively (P = 0.037). Furthermore, the number of embryos either transferred or frozen was significantly higher in the IVF group than the ICSI group: 459 of 1173 (39.1%) and 385 of 1268 (30.4%), respectively (P < 0.0001). These data indicate that conventional IVF results in a higher fertilization rate than ICSI. Furthermore, IVF provided more embryos available for transfer or cryopreservation when compared with ICSI, thereby optimizing the patient's cycle.

Comparison of bovine- and recombinant human-derived hyaluronidase with regard to fertilization rates and embryo morphology in a sibling oocyte model: a prospective, blinded, randomized study.

The objective of the present study was to compare a traditionally used bovine-derived hyaluronidase (Hyase) with the newly developed recombinant human-derived enzyme product (Cumulase) in intracytoplasmic sperm injection (ICSI) procedures using a sibling oocyte model in a prospective randomized design. The results of the study demonstrate that Cumulase is safe and effective in an ICSI treatment program and can provide comparable if not improved parameters, including fertilization and embryo developmental rates.

Comparison of laser-assisted hatching and acidified Tyrode's hatching by evaluation of blastocyst development rates in sibling embryos: a prospective randomized trial.

OBJECTIVE: To assess two zona drilling methods in terms of blastocyst development rates using sister embryos. DESIGN: Prospective, randomized study. Sister embryos of 14 patients were randomly assigned on day 3 to acidified Tyrode's zona drilling or to laser zona drilling. After biopsy, subsequent embryo culture until the blastocyst stage (day 5) was performed. SETTING: Private fertility center. PATIENT(S): Patients undergoing IVF-preimplantation genetic diagnosis. INTERVENTION(S): Embryo biopsy using either laser-assisted hatching or acidified Tyrode's hatching on sibling embryos and subsequent blastocyst development evaluation. MAIN OUTCOME MEASURE(S): Evaluation of blastocyst development in terms of degree of expansion and cell number in the inner cell mass and trophectoderm. RESULT(S): Blastocyst development rates (and blastocyst quality) were similarly high in both the acidified Tyrode's hatching group and the laser-assisted hatching group. CONCLUSION(S): Laser hatching does not impair embryonic development to the blastocyst stage, demonstrating that laser-assisted hatching is a suitable alternative to the use of acidified Tyrode's solution for zona drilling.

Effect of reduced oocyte aging on the outcome of rescue intracytoplasmic sperm injection.

OBJECTIVE: To evaluate the results of a novel protocol that allows to rescue IVF unfertilized oocytes by intracytoplasmic sperm injection (ICSI). DESIGN: Prospective clinical trial. SETTING: Private reproductive medical center. PATIENT(S): Thirty patients undergoing IVF. INTERVENTION(S): Controlled ovarian stimulation (COS), conventional IVF, rescue ICSI, embryo culture, and embryo transfer. MAIN OUTCOME MEASURE(S): Identification of unfertilized IVF oocytes 6 hours after insemination and fertilization, and developmental rates of those oocytes after rescue microinjection, as well implantation and pregnancy rates (PR). RESULT(S): All oocytes (392) from 30 patients were inseminated with standard IVF 3 hours after ovum pick-up. Polar body (PB) status was checked at decumulation and rechecked 3 hours later. Eighty-two oocytes were fertilized after IVF alone and 184 nonactivated oocytes (failed fertilization) were rescue microinjected and 166 of them fertilized (20 patients). Cleavage stage on day 2 was significantly more advanced and embryo grade was higher after standard IVF fertilization than after rescue ICSI. Eight of the 30 embryos transferred were implanted in the IVF-only patients (27%) and 8 of 68 embryos in the rescue ICSI patients (12%). CONCLUSION(S): Rescue ICSI of unfertilized IVF oocytes 6 hours after insemination (9 hours after egg retrieval) can provide normal fertilization, embryo development, and pregnancy; however, corresponding outcome parameters tend to be impaired in comparison to the standard IVF fertilization results.

Removal of lysed blastomeres from frozen-thawed embryos improves implantation and pregnancy rates in frozen embryo transfer cycles.

OBJECTIVE: To evaluate the effect of degenerated (lysed) blastomere removal on implantation and pregnancy rates in cleavage-stage cryo-embryo transfer (ET) cycles. DESIGN: Randomized clinical trial. SETTING: Private reproductive medical center. PATIENT(S): A total of 88 patients who received frozen-thawed ET, divided into two groups. INTERVENTION(S): Embryo freezing and thawing; opening of the zona pellucida and removal of cryodamaged blastomeres (in the study group), followed by same-day ET. MAIN OUTCOME MEASURE(S): Extent of survival of cleavage-stage embryos after the freeze-thaw procedure; embryo implantation and clinical pregnancies. RESULT(S): Oocyte number per patient, fertilization rate, embryo development rate (and quality), and freezing rates were similar in the two groups in the fresh cycle. In the control group, a total of 55 embryos (25%) of the 217 thawed remained fully intact, and 53 (26%) of the 207 in the study group remained intact. The average number of embryos transferred per group was similar (control, 3.4 +/- 0.9; study, 3.3 +/- 0.9). Implantation rates were 12% and 26% in the control and study groups, respectively. The clinical pregnancy rate was 23% in the control group and 64% in the study group when lysed cell removal was performed. CONCLUSION(S): The results show that pregnancy and implantation rates are higher in the study group; therefore, the removal of degenerated blastomeres may be beneficial to all patients who undergo cleavage-stage, frozen-thawed ET.

Uterine cavity findings and hysteroscopic interventions in patients undergoing in vitro fertilization-embryo transfer who repeatedly cannot conceive.

OBJECTIVE: To assess hysteroscopic findings in patients undergoing IVF-ET who repeatedly failed to conceive despite transfer of good-quality embryos. DESIGN: Prospective, observational study. SETTING: Clinical research unit for reproductive medicine in a private clinic. PATIENT(S): Fifty-five patients with a normal uterine cavity on hysterosalpingography before the initial IVF-ET cycle and two previous failed IVF-ET attempts despite transfer of a minimum of two good-quality embryos on each occasion. INTERVENTION(S): Standard transvaginal ultrasonography and diagnostic and therapeutic hysteroscopy. MAIN OUTCOME MEASURE(S): Endometrial findings on transvaginal ultrasonography and hysteroscopy and outcome of the cycles after surgical hysteroscopy and antibiotic therapy. RESULT(S): Twenty-five (45%) patients had abnormal endometrial findings and underwent treatment to correct the lesions. All patients underwent a third IVF-ET cycle. Pregnancy (50% vs. 20%) and implantation (19% vs. 5.5%) rates were significantly higher in patients who were treated for uterine abnormalities than in patients who had normal uterine cavities on hysteroscopy. CONCLUSION(S): The incidence of pathologic findings on hysteroscopy is high in patients with repeated failures of IVF-ET. Evaluation of endometrial integrity by hysteroscopy is highly valuable and should be applied to all such cases.

Pronuclear morphology evaluation with subsequent evaluation of embryo morphology significantly increases implantation rates.

OBJECTIVE: To elucidate the relative predictive value of implantation markers at different stages of preimplantation development. DESIGN: Correlation of pronuclear morphology with embryo morphology and implantation rates in retrospective and prospective analysis of in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI) treatment cycles. SETTING: Private infertility center. PATIENT(S): A total of 441 couples undergoing infertility treatment. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Size of pronuclei and distance between them, the number and polarization of nucleolus precursor bodies (NPB) at the one-cell stage, embryo cleavage and fragmentation rates on days 2 and 3, and pregnancy and implantation rates. RESULT(S): Polarization of the NPB in both pronuclei had a statistically significant correlation with normal membrane breakage during ICSI (40%, compared with 33% easy, and 31% difficult membrane breakage) and also with faster cleavage and lower fragmentation rates of embryos. Sixty-one percent of implanting embryos had polarization of the NPB in both pronuclei compared with 37% for all embryos. Larger distance between pronuclei and their unequal size had a statistically significant correlation with slower cleavage and inferior embryo quality. Embryo selection based on only pronuclear morphology or on only day-3 embryo morphology yielded implantation rates of 15.1% and 12.1%, respectively. Embryo selection based on sequential evaluation of both pronuclear morphology and embryo morphology on day 3 resulted in a 21.1% implantation rate. CONCLUSION(S): Polarization of NPB in both pronuclei is as reliable marker of implantation as embryo morphology on day 3. However, pronuclear morphology assessment improves embryo selection only when it is combined with embryo morphology evaluation on day 3.

Novel use of laser to assist ICSI for patients with fragile oocytes: a case report.

An inadvertent consequence of intracytoplasmic sperm injection (ICSI) is the degeneration of some of the microinjected oocytes. Most patients may not suffer any disadvantage through losing oocyte(s) during micromanipulation; however, in some circumstances, this can result in a reduction of the chances for pregnancy. This study reports a clinical pregnancy obtained by a novel approach using laser-assisted micro-opening of the zona pellucida prior to ICSI to secure a non-traumatic microinjection that avoids degeneration of oocytes. A total of 12 oocytes were obtained from the 36 year old patient in her third IVF treatment cycle, following two previously failed attempts where very high degeneration rates of oocytes after ICSI were recorded, together with suboptimal embryo quality. Five of the 11 matured (MII) oocytes were submitted to conventional ICSI and the other six MII oocytes first underwent laser-assisted opening of the zona pellucida (5-7 microm hole size was created with a 1.48 microm diode laser) before microinjection (LA-ICSI). Three of the five conventionally microinjected oocytes degenerated while one oocyte fertilized normally and developed to a good quality embryo. After the LA-ICSI procedure, one of the six oocytes degenerated and four oocytes fertilized normally; of these, two developed to excellent quality embryos, one to a good quality embryo and one to a poor quality embryo. The three best embryos (LA-ICSI group) were transferred to the patient on day 3. Rising serum human chorionic gonadotrophin concentrations were measured 12 days after transfer and on week 7 two implantation sites were detected, together with regular heart activity. The results of the present report suggest that laser-assisted ICSI may provide a safer approach to non-traumatic microinjection of oocytes than conventional ICSI, thereby minimizing the risk of degeneration and possibly also improving embryo quality. Therefore, it is suggested that laser-assisted ICSI might be applied in all cases associated with difficult zona pellucida penetration or/and fragile oolemma, or where patients have very few oocytes available, to improve the chances for pregnancy.

Relationship between time period after vasectomy and the reproductive capacity of sperm obtained by epididymal aspiration.

BACKGROUND: It is not well defined whether the elapsed time after vasectomy has any influence on the outcome of IVF-ICSI using epididymal sperm. We analysed retrospectively the results of 151 ICSI cycles in which sperm of vasectomized men were used at different time periods after vasectomy. METHODS: Oocytes were obtained after a desensitizing ovarian stimulation protocol using GnRH agonist in association with recombinant FSH and HCG. Sperm were retrieved by percutaneous epididymal sperm aspiration. The cycles were split into three groups: < or =10 years after vasectomy (group 1, n = 47), 11-19 years after vasectomy (group 2, n = 79), and > or =20 years after vasectomy (group 3, n = 25). RESULTS: As might be expected, the mean age of men differed in the three groups (group 3 > group 2 > group 1), and the mean age of the women was also significantly higher in group 3 than in groups 1 and 2, although no differences were described between groups 2 and 3. All other laboratory and clinical parameters were similar in the three groups. Ongoing pregnancy and implantation rates (34, 25, 8% and 22, 15, 6% respectively) decreased significantly from group 1 to group 3. CONCLUSION: Pregnancy and implantation rates after ICSI with sperm from vasectomized men are negatively correlated with the time interval from vasectomy, which cannot be explained purely by male or female ageing.

ICSI and day 5 embryo transfers: higher implantation rates and lower rate of multiple pregnancy with prolonged culture.

This retrospective review study, carried out in a private IVF clinic, compared pregnancy and implantation rates with day 3 versus day 5 embryo transfers in a selected group of patients. Participants were patients who failed to achieve pregnancy in at least one previous attempt with embryo transfer on days 2 or 3, and had more than five oocytes fertilized. A total of 296 patients who had undergone day 3 (group A) transfers were compared with 154 who had undergone day 5 transfers (group B). Interventions were intracytoplasmic sperm injection (ICSI), day 3 and day 5 embryo transfer. Outcome measures were pregnancy, implantation, multiple gestation and blastocyst formation rates. Overall, 86.4% of embryos were at the six- to eight-cell stage at 72 h and 30% developed to blastocyst by day 5. The mean number of embryos transferred was 4.0 on day 3 and 3.0 on day 5. Pregnancy and implantation rates were 34.8 and 11.5% in group A, versus 45.3 and 18.5% in group B. Multiple gestation rate was 47.1% in group A and 28.5% in group B. Prolonging embryo culture in vitro to day 5 improved embryo selection and implantation rates. A significant decrease in high order gestations was achieved by reducing the number of embryos transferred, without compromising the pregnancy rates.