Search

This study was undertaken to explore whether intervention with heparin and aspirin (H/A) in selected patients undergoing in-vitro fertilization (IVF) and embryo transfer could improve fecundity rates. Specifically, it explored the possibility that women diagnosed with organic pelvic disease who demonstrated antiphospholipid antibodies (APA) could benefit from H/A administration in a similar manner to that used in patients with recurrent pregnancy loss. We used an enzyme-linked immunosorbent assay for six different phospholipids to identify patients who expressed APA before they underwent IVF/embryo transfer. This study was confined to the first IVF/embryo transfer cycle that followed assessment of APA status and accordingly, the number of IVF/embryo transfer cycles corresponds with the number of patients treated. APA seropositive patients were treated with aspirin, 81 mg orally q.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 of controlled ovarian stimulation. The endpoint for success was a live birth or an ultrasound confirming fetal cardiac activity (a viable pregnancy). The prevalence of APA in patients diagnosed with organic pelvic disease (53%) was much higher than in those without female pathology (14%). The administration of H/A to APA seropositive patients significantly (P < 0.05) improved the viable pregnancy rate (49%) compared to the untreated APA seropositive group (16%). The viable pregnancy rate for APA seropositive women treated with H/A was also significantly (P < 0.001) higher than for untreated APA seronegative patients (27%). We conclude that all women undergoing IVF/embryo transfer should be tested for APA prior to initiating ovarian stimulation and those with APA seropositivity should be treated with H/A. [ABSTRACT FROM AUTHOR]

Recent reports in the literature have focused on the increased risk of heterotopic pregnancy after the transfer of multiple concepti or oocytes. In an international collaborative patient registry between 1985 and 1989, 601 clinical pregnancies resulted from 2092 gamete intra-Fallopian transfer (GIFT) retrieval cycles. Five of the pregnancies were heterotopic (0.83%). After surgical intervention, all five cases of combined gestation resulted in live birth from intrauterine pregnancies. Routine vaginal ultrasonographic examination of the adnexa in patients who conceive after GIFT may help early diagnosis of heterotopic pregnancy. If the diagnosis is made early, conservative treatment may preserve the future fecundity of the patient and more intrauterine pregnancies may be salvaged. [ABSTRACT FROM PUBLISHER]

Embryo chromosome studies show high rates of abnormalities, above 50%, but most embryos studied were from patients aged 35 and older. The objectives of this study were firstly, to evaluate the rate of chromosome abnormalities in embryos from young egg donors, and secondly, to compare the range of chromosome abnormality rates between donors and non-egg donor cycles, both undergoing preimplantation genetic diagnosis (PGD) for infertility using fluorescence in-situ hybridization analysis with probes for chromosomes X, Y, 13, 15, 16, 18, 21, and 22. On average, only 43% of the embryos were chromosomally normal, while the comparison group had euploidy rates between 34 (age group 18-34) (P < 0.001) and 21% (age group 40-45) (P < 0.001). There was considerable variation between donor cycles, with almost one-third having less than 30% normal embryos. Also, within donors and recipients repeating several IVF cycles with PGD, only 29-56% of the second PGD cycles had similar rates of normal embryos to the first cycle, while in the comparison group it was 64%. The results can explain why some egg donors are successful whereas others are not, and may also show that a policy of PGD for first time egg donors is appropriate and indicated. [ABSTRACT FROM AUTHOR]

The health risks associated with transferring embryos classified as mosaic by preimplantation genetic testing for aneuploidies (PGT-A) are currently unknown. Such embryos produce PGT-A results indicating the presence of both euploid and aneuploid cells and have historically been deselected from transfer and grouped with uniformly aneuploid embryos as 'abnormal'. In recent years, numerous groups have reported the intentional transfer of mosaic embryos in the absence of uniformly euploid embryos, largely observing births of seemingly healthy babies. However, it remains to be understood whether the embryonic mosaicism invariably becomes resolved during the ensuing pregnancy, or whether the placenta and/or fetal tissues retain aneuploid cells, and if so to what potential clinical effect. Here, we report two cases of mosaicism persisting from the embryonic stage to the established pregnancy. Case 1 involved an embryonic low-level segmental mosaic loss in Chromosome (Chr) 1, which was confirmed in amniocentesis as well as in brain tissue of the products of conception. This pregnancy was terminated due to the chromosomal pathologies associated with 1p36 deletion syndrome, such as severe intellectual disability. Case 2 involved a low-level mosaic Chr 21 trisomy, which was confirmed with chorionic villus sampling and amniocentesis. The ensuing pregnancy was terminated after ultrasound identification of severe abnormalities in the placenta and fetus. Together, these two cases should be taken into account for risk-benefit assessments of prospective mosaic embryo transfers., (© The Author(s) 2023. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Research Question: Conflicting data exist on the utility of quantification of mitochondrial DNA (mtDNA) levels as a predictor of blastocyst implantation in the IVF clinic. The current study determined whether blastocysts with highly elevated mtDNA levels could result in healthy pregnancies and births, and whether mitochondrial functional output might be a readout of cell stress in the embryo., Design: mtDNA levels were determined in 109 blastocysts used in clinical transfers into 100 women, noting their clinical outcomes. In a separate set of embryos, mitochondrial function was quantified in a model of embryo stress, aneuploidy. Measurement of mtDNA levels made use of surplus material from the process of preimplantation genetic testing for aneuploidies, and followed recently proposed unifying guidelines for mtDNA quantification., Results: Unusually high mtDNA levels did not preclude blastocyst implantation and healthy births. An analysis of 109 blastocysts showed no significant difference between mtDNA levels in implanted (n = 55) versus non-implanted (n = 54) blastocysts. No obvious differences in the degree of mitochondrial functional output were detected in a model of embryo stress., Conclusions: Measurement of mtDNA copy number might not provide any advantage in embryo prioritization and could lead to a deselection of blastocysts that would result in healthy pregnancies and births. Furthermore, the quantification of mitochondrial functional output in a model of cellular stress might suggest that mitochondria are not clear targets for biomarker identification as it relates to blastocyst viability. Any suggested link between mtDNA levels, mitochondria or their output with blastocyst transfer outcome requires further validation., (Copyright © 2019 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Objective: The inicidence of miscarriage is correlated with maternal age. The majority of miscarriages are chromosomally abnormal. The purpose of this study was to determine in a large population of infertility patients (>2000 cycles) if preimplantation genetic diagnosis (PGD) reduced the rate of spontaneous abortions., Design: Multicenter retrospective controlled study., Setting: One hundred IVF centers referring samples to a reference PGD laboratory., Patient(s): Infertile women., Intervention(s): The spontaneous abortion rate after PGD was retrospectively compared to non-PGD cycles from the 2002 American Society for Reproductive Medicine-Society for Assisted Reproduction Technology report on IVF cycles., Main Outcome Measure(s): Spontaneous abortions and trisomic offspring rates., Result(s): The study included 2,279 cycles of PGD. The pregnancy rate per retrieval was 26.7% (average age 39.6). The mean pregnancy loss for the PGD group (0.167) was significantly lower than for the general IVF group (0.215) (P<.001). After PGD, the spontaneous abortion rate was 14.1% for ages 35-40, and 22.2% for women over 40, compared to 19.4% (P=.03) and 40.6% (P<.001), respectively, in controls. The clinical error rate of PGD (1.2%) was significantly lower than expected (4.7%) (P<.001)., Conclusion(s): The data suggests that PGD significantly reduces the risk of spontaneous abortions in women undergoing IVF and PGD, particularly in women over 40. In addition, PGD may also reduce the risk of trisomic offspring.

Problem: The effect of mini-dose heparin/aspirin (H/A) alone vs. combined intravenous immunoglobulin G (IVIg) and H/A on in vitro fertilization (IVF) birthrates in women who test seropositive for antiphospholipid antibodies (APA+) was evaluated, as was the question of whether outcome is influenced by the gammaglobulin isotype(s) or the phospholipid (PL) epitope(s) to which the APAs are directed., Method of Study: A case-control study was conducted in three phases, spanning a 4-year period, in a multicenter clinical research environment. Six hundred eighty-seven APA+ women, who were younger than 40 years and who each, completed up to three consecutive IVF/embryo transfer cycles within a 12-month period, were given either H/A alone or H/A in combination with IVIg. Birthrates relative to the type of immunotherapy (i.e., H/A alone and H/A with IVIg) and APA profile were the main outcome measurements., Results: In phase I, 687 women who tested APA+ to one or more PL epitopes underwent two or fewer IVF attempts for a total of 1050 IVF cycles. Four hundred seventy-seven (46%) births occurred in 923 IVF cycles in which H/A alone was administered. Twenty-two (17%) births occurred after 127 IVF cycles in which H/A was not administered. In phase II, 322 of 687 women tested positive for a single APA subtype. These subjects underwent up to two consecutive IVF attempts for a total of 521 IVF cycles while receiving H/A alone. The birthrate was significantly lower for women whose APAs were directed toward phosphatidylethanolamine (PE) or phosphatidylserine (PS) involving IgG or IgM isotypes than for women who had any other APA (17% vs. 43%). In phase III, 121 women who did not achieve live births after two consecutive IVF attempts in which H/A alone was administered received IVIg in combination with H/A during their third consecutive IVF cycle. The birth rate was 41% after these IVF cycles when anti-PS or anti-PE involving IgG or IgM isotypes were present, as compared with 17% when H/A alone was administered. The IVF outcome did not improve when IVIg was administered in association with any other single APA., Conclusions: The treatment of APA+ women with H/A alone improves IVF birthrates. This benefit is selective in that it does not apply in cases in which IgG- or IgM-related APAs are directed against PE or PS. In such cases, the addition of IVIg significantly improves the outcome.

Problems: 1) Does the administration of heparin and aspirin (H/A) in combination with intravenous immunoglobulin G (IVIG) improve in vitro fertilization (IVF) implantation and birth rates in patients with recurrent IVF failure? 2) Is the effect of such treatment related to the antiphospholipid antibody (APA) status of the patients concerned?, Method of Study: Subjects consisted of 89 women younger than 36 years of age whose infertility was a result of causes other than male infertility and who had experienced four or more failed IVF/embryo transfer procedures. Fifty-two women were APA+ (group A), and 37 were APA- (group B). All patients, regardless of their APA status, received H/A (5000 U sq bid), aspirin (81 mg po qd) from the inception of menotropin therapy along with IVIG (20 g) through a single infusion 3 to 10 days before egg retrieval., Results: Twenty-two (42%) of group A and 7 (19%) of group B patients achieved live births (P = 0.020)., Conclusions: IVF outcome is significantly improved when H/A and IVIG are administered to APA+ women with repeat IVF failures. APA- women do not seem to benefit from such treatment.

Problem: To compare the effect of heparin/aspirin therapy alone vs. heparin/aspirin in combination with intravenous immuno-globulin (IVIg) immunotherapy on in vitro fertilization (IVF) outcome of patients who test positive for antithyroid antibodies (ATAs)., Method of Study: Eighty-two women younger than 40 years of age whose infertility was related exclusively to female causes were evaluated. All tested positive for organ-specific antithyroid antibodies (antimicrosomal and/or antithyroglobulin antibodies), but negative for antiphospholipid antibodies. Thirty-seven of these women (group A) received H/A alone, whereas 45 (group B) received heparin/aspirin in combination with IVIg., Results: Ten (27%) of women in group A and 23 (51%) of women in group B achieved live births after completion of a single IVF/embryo transfer cycle (P = 0.027)., Conclusion: We conclude that IVIg therapy significantly improves IVF success rates in ATA+ women.

Objective: To evaluate the efficacy of zygote intrafallopian transfer (ZIFT) versus standard IVF-ET for the treatment of nontubal factor infertility., Design: A prospective randomized trial., Participants: Fifty-nine couples undergoing oocyte retrieval for nontubal infertility in a university hospital-based IVF-ET program., Interventions: A maximum of four cleaving embryos were transferred into the fallopian tube or uterine cavity 48 or 55 hours after oocyte retrieval, respectively., Main Outcome Measures: Rates of implantation, pregnancy, and spontaneous abortion (SAB) were compared., Results: Clinical pregnancies occurred after 26.5% versus 12% of retrievals and 29% versus 14.3% of transfers in IVF-ET versus ZIFT cycles, respectively. Pregnancy, implantation, and SAB rates did not differ between the groups., Conclusions: This prospective randomized trial failed to demonstrate any therapeutic improvement associated with the increased complexity of ZIFT as compared with standard IVF-ET.

Objective: To evaluate a new method for preventing the life-endangering complications associated with inadvertent menotropin-induced severe ovarian hyperstimulation in patients undergoing in vitro fertilization and embryo transfer (IVF-ET)., Methods: Seventeen women each underwent a single cycle of controlled ovarian hyperstimulation with menotropins in preparation for IVF-ET. The indications for IVF-ET were tubal occlusion in nine, endometriosis in six, and unexplained infertility in two. The peak plasma estradiol (E2) concentration before hCG administration was greater than 6000 pg/mL and more than 30 ovarian follicles were detected by transvaginal ultrasound. Thus, life-endangering complications associated with severe ovarian hyperstimulation syndrome were highly likely to occur following hCG administration. Rather than cancel the cycle of treatment, menotropin therapy was discontinued and hCG administration was deferred for a number of days until the plasma E2 concentration fell below 3000 pg/mL ("prolonged coasting"), whereupon hCG was administered and egg retrievals and ETs were duly performed., Results: None of the women developed severe ovarian hyperstimulation syndrome. There were six viable pregnancies (35.2%), which proceeded normally., Conclusion: This study indicates that "prolonged coasting" prevents severe ovarian hyperstimulation syndrome in severely overstimulated women undergoing IVF-ET, without necessitating cycle cancellation.

Objectives: To determine the extent of contamination of ovarian follicular fluid and serum samples in women undergoing in-vitro fertilization and to study the effect of the contaminants on reproductive outcome., Design: Inception cohort study., Patients: Seventy-four women undergoing in-vitro fertilization at three regional clinics in Halifax, Hamilton, Ont., and Vancouver., Main Outcome Measures: Follicular fluid and serum levels of contaminants, cleavage rates and time to cleavage of first egg., Results: Five chlorinated organic chemicals were frequently found in the two types of samples: alpha-chlordane (ALCH), dichlorochlorophenylethylene (DDE), heptachloroepoxide-oxychlordane (OXCH), hexachlorobenzene (HCB) and polychlorinated biphenyl (PCB). The levels were generally low. Regional differences between the three clinics were present. Samples from the Halifax clinic had the lowest frequency and level of contamination. The source of drinking water (well, bottled or municipal) was an important confounder. The concentrations of the five contaminants did not affect the cleavage rate or the time to cleavage of the first egg., Conclusion: Trace amounts of toxic and persistent chlorinated organic chemicals found in the follicular fluid of Canadian women undergoing in-vitro fertilization did not seem to have any adverse biologic effect on the rate of fertilization and the time to cleavage. Reasons for regional differences in the concentrations of contaminants require further study.

Objective: To assess the outcome of in vitro fertilization and embryo transfer (IVF-ET) in women with refractory polycystic ovarian syndrome (PCOS)., Design: Retrospective case series with an age-matched control group., Setting: Ovulation induction and IVF programs in a tertiary referral center., Patients and Interventions: Nine patients with PCOS who failed standard ovulation induction treatment (clomiphene citrate plus greater than or equal to 6 ovulatory human menopausal gonadotropin [hMG] cycles) underwent 19 cycles of IVF-ET. Forty age-matched tubal factor patients who completed 40 cycles of IVF-ET served as a control group., Outcome Measures: Demographic features and IVF-ET cycle characteristics were compared using Student's t-test and Fisher's exact test., Results: Cycles of IVF-ET in patients with PCOS were associated with higher estradiol levels (5,222 versus 4,009 pmol/L), lower hMG requirements (15.8 versus 19.6 vials), greater numbers of oocytes (7.6 versus 5.6), and lower fertilization rates (56% versus 75%) compared with tubal factor cycles (P less than 0.05). However, the number of embryos transferred (3.9 versus 4.0) and the clinical pregnancy rate per embryo transfer (24% versus 25%) did not differ significantly between the two groups., Conclusion: These results suggest that conception failure after six or more ovulatory hMG cycles in patients with PCOS does not adversely affect subsequent IVF performance.

This study analyzed the intraoperative morbidity, postoperative course, postoperative hospital stay and fertility outcome in 216 consecutive tubal pregnancies treated with either laparoscopy (n = 98) or laparotomy (n = 118). Among the 98 cases treated with laparoscopy, the procedure was successfully completed in 95 (97%). In three cases laparotomy had to be performed to conclude the procedure. Retained trophoblast was observed in 3.8% of cases treated conservatively with laparoscopy and 1.3% of cases treated conservatively with laparotomy (P greater than .05). The total anesthesia time, amount of postoperative analgesia required and postoperative hospital stay were significantly less in cases treated with laparoscopy (P less than .001). The subsequent fertility outcome was similar in both groups. Laparoscopic treatment of tubal pregnancy is a safe and effective alternative to laparotomy, yielding similar fertility outcomes and requiring significantly less postoperative analgesia and a significantly shorter hospital stay.

While pregnancies have been documented through the independent use of the vibrator method, from other methods of procuring ejaculate from spinal cord injured men, and from artificial insemination using a retrograde specimen, we believe that this is the first case report of a live birth resulting from a retrograde ejaculate obtained by vibration from a spinal cord-injured male whose partner underwent in vitro fertilization. Vibrostimulation may well be successful in the two-thirds of men whose spinal cord lesions are at the T10 neurological level and above, who have an intact bulbocavernosus reflex and anal tone but no pain or temperature sensation of the genitalia. Blood pressure monitoring, prevention of autonomic dysreflexia, alkalinization, dilution and infection control of urine, and retrograde specimen retrieval are all important techniques to ensure patient safety and optimal ejaculates. The timing of ovulation and insemination is the crucial factor for the partner of a SCI male whose sperm quality is poor. A complete gynecological workup, including studies of tubal patency, should be done before embarking on a series of artificial inseminations. Stimulation of ovulation and well-timed inseminations should optimize the chance of conception. Depending on semen analysis, female partner factors, and emotional and financial costs, IVF can appropriately be either an early or a final option.

Data were collected from self-administered questionnaires returned by 33 female participants and 18 of their partners in the University of British Columbia's in Vitro Fertilization/Gamete Intrafallopian Transfer (IVF/GIFT) Program during a 2-month period. Emotional reactions to each of the stages of IVF/GIFT by treatment phase were measured. Responses were then grouped into the following categories: anxiety, depression, loss of control, and positive feelings. For female participants, anxiety was reported most frequently throughout the treatment process and loss of control was highest following embryo replacement. Male and female participants reported high rates of depression at the completion of the treatment cycle. The findings from this pilot study outline the emotional experiences of male and female participants undergoing IVF/GIFT by treatment phase and indicate their desire for support services.

Objective: To determine incidence of hypospadias in infants born as a result of assisted reproductive technology (ART)., Design: Prospective data collection., Setting: Parents with various forms of infertility attended an in-hospital in vitro fertilization program., Patients: Two of the 53 male infants, conceived as a result of ART over a 3-year period, were born with hypospadias., Interventions: Patient no. 1 underwent follicular stimulation (17 ampules of human menopausal gonadotropin (hMG), followed by 10,000 IU of human chorionic gonadotropin (hCG) 60 hours after the last hMG). Patient no. 2 underwent follicular stimulation with clomiphene citrate 100 mg/d from days 3 to 7, followed by 14 ampules of hMG starting day 6, and 10,000 IU of hCG 30 hours after her last hMG., Main Outcome Measures: All infants were examined in the immediate postpartum period for congenital anomalies., Results: Infant no. 1, one of a set of dizygotic twins, had penoscrotal hypospadias, with normal renal sonogram and chromosomal studies. Infant no. 2 had glandular hypospadias with the urinary meatus displaced to the border of the glans., Conclusion: This high incidence raises concern about possible links between assisted reproduction and hypospadias.

Objective: To assess predisposing factors to tubal pregnancy after in vitro fertilization-embryo transfer (IVF-ET)., Design: Retrospective analysis of 891 ET cycles., Setting: University-based IVF program., Patients, Participants: All ET cycles performed in the study period were included; the indication for IVF was tubal factor in 640 (72%) and other (nontubal) factors in 251 (28%) cycles., Interventions: None., Main Outcome Measure: Observing a higher than expected number of tubal pregnancies in our program; we examined subgroups to determine those at highest risk., Results: Tubal pregnancies comprised 12% of clinical pregnancies in the tubal factor group but only 2.6% in the cycles nontubal factor group (P less than 0.05). Of 640 ET cycles in the tubal factor group, 359 were performed in patients who had prior tubal reconstructive surgery; tubal pregnancies comprised 15.6% of the clinical gestations in this subgroup. In the remainder of the tubal factor group (no prior tubal surgery), 281 ET cycles yielded a tubal pregnancy rate of only 5.5% (P less than 0.05)., Conclusions: Women with prior reconstructive surgery for distal tubal disease are at highest risk of developing tubal pregnancy after IVF.

Objective: To determine if a simple morphological classification of embryos was predictive of subsequent pregnancy., Design: Prospective case series., Setting: University-based in vitro fertilization (IVF) program., Patients, Participants: Consecutive embryo transfer (ET) cycles (n = 206)., Interventions: Embryos were classified into three grades: (1) equal-size blastomeres with no fragmentation; (2) unequal-size blastomeres; and (3) evidence of fragmentation., Main Outcome Measures: Embryo quality, age, indication for IVF, and stimulation protocol were evaluated for their effect on pregnancy rates (PR's)., Results: In cycles in which the best embryo transferred was grade 3, 2, or 1, the clinical PRs per ET were 0% (0/11 cycles), 12.8% (6/47 cycles, P less than 0.05), and 21.8% (32/148 cycles, P less than 0.05), respectively. When one, two, or three or more grade 1 embryos were replaced, the clinical PRs per ET were 15.6%, 16.3%, and 40% (P less than 0.05), respectively. Using logistic regression, embryo quality (P = 0.0011) and patient's age (P = 0.0044) were the only variables that affected PRs., Conclusion: The transfer of more than two good quality embryos had a positive effect, patient's age had a negative effect on PRs after IVF-ET.

This study was undertaken to analyze the factors associated with fertility outcome following tubal pregnancy. Eighty-six patients were analyzed in this regard. The chances of a favourable outcome (intrauterine pregnancy) decreased and an unfavorable outcome (repeated tubal pregnancy or no pregnancy) increased with a history of previous tubal pregnancy and also with an absent or diseased contralateral tube at the time of surgery. History of infertility, prior reconstructive tubal surgery, status of the ipsilateral tube at the time of surgery, the treatment modality (laparoscopy vs laparotomy) or the surgical approach (conservative vs radical) did not significantly affect fertility outcome.

Chromosome preparations were made from 25 cleaved abnormal human embryos at the two- to eight-cell stage after in vitro fertilization. Morphologically, these embryos showed either variable degrees of degeneration or an abnormal number of pronuclei before first cleavage. Among 14 successfully karyotyped embryos, only 3 had a normal chromosomal complement. Eleven showed chromosomal abnormalities, including triploidy, haploidy, and mosaicism. This finding documents a high incidence of chromosomal errors in morphologically abnormal early preimplantation embryos.

To assess the contribution of chromosome anomalies to the high failure of in vitro fertilization (IVF), 94 unfertilized eggs from 43 women participating in the IVF program were cytogenetically investigated. The mean age of the oocyte donors was 33.6 years. Chromosome karyotypes were obtained in 65 of 94 oocytes: 34 oocytes (52.3%) had a normal haploid chromosome complement; 10 (15.4%) were hypohaploid; 7 (10.8%) were hyperhaploid; 8 were diploid; and 6 were hypodiploid or hyperdiploid (from 36 to 53). Eleven eggs showed prematurely condensed chromosomes of the G1-phase from sperm, as well as a set of maternal metaphase II chromosomes. These results are compared to similar reports in the literature.

Patients with recurrent spontaneous abortions have been successfully treated in many centers with third-party immunization directed to a putative TLX antigen system. This immunotherapy requires the screening of a large number of donors to match the patients' red blood cell (RBC) phenotype and has the potential risks associated with transfusions from 30 to 50 donors. Our modified approach to third-party immunization is to use irradiated frozen-stored purified lymphocytes pooled from five normal donors. Mononuclear cells from normal donors are obtained in a cell separator. After sedimentation and Ficoll-Hypaque separation, the cells are stored in liquid N2. The RBC depletion of the final preparation is of the order of 5 to 6 logs, theoretically decreasing the need for RBC phenotyping except for the Rh system. Using a highly sensitive fluorescence-activated cell sorter technique and an ADCC assay, we found that ABH, Rh, Fya Fyb, Jka Jkb, MNS, and Kell antigens are either not expressed by cryopreserved human mononuclear cells, or, if so, they are below the level of detection of these highly sensitive assays. We conclude that the use of pooled frozen mononuclear cells is an adequate alternative for immunotherapy. It decreases the transfusion risks associated with exposure to a large number of donors and the need for RBC phenotyping, making this modality of treatment more accessible.