The 2019 PGDIS position statement on transfer of mosaic embryos within a context of new information on PGT-A.

BACKGROUND: A recently published Position Statement (PS) by the Preimplantation Genetics Diagnosis International Society (PGDIS) regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF) contained inaccuracies and misrepresentations. Because opinions issued by the PGDIS have since 2016 determined worldwide IVF practice, corrections appear of importance. METHODS: The International Do No Harm Group in IVF (IDNHG-IVF) is a spontaneously coalesced body of international investigators, concerned with increasing utilization of add-ons to IVF. It is responsible for the presented consensus statement, which as a final document was reached after review of the pertinent literature and again revised after the recent publication of the STAR trial and related commentaries. RESULTS: In contrast to the PGDIA-PS, we recommend restrictions to the increasing, and by IVF centers now often even mandated, utilization of PGT-A in IVF cycles. While PGT-A has been proposed as a tool for achieving enhanced singleton livebirth outcomes through embryo selection, continued false-positive rates and increasing evidence for embryonic self-correction downstream from the testing stage, has led IDNHG-IVF to conclude that currently available data are insufficient to impose overreaching recommendations for PGT-A utilization. DISCUSSION: Here presented consensus offers an alternative to the 2019 PGDIS position statement regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF). Mindful of what appears to offer best outcomes for patients, and in full consideration of patient autonomy, here presented opinion is based on best available evidence, with the goal of improving safety and efficacy of IVF and minimizing wastage of embryos with potential for healthy births. CONCLUSIONS: As the PGDIS never suggested restrictions on clinical utilization of PGT-A in IVF, here presented rebuttal represents an act of self-regulation by parts of the IVF community in attempts to control increasing utilization of different unproven recent add-ons to IVF.

The total pregnancy potential per oocyte aspiration after assisted reproduction-in how many cycles are biologically competent oocytes available?

PURPOSE: While stimulation of women prior to assisted reproduction is associated with increased success rates, the total biological pregnancy potential per stimulation cycle is rarely assessed. METHODS: Retrospective sequential cohort study of the cumulative live birth rate in 1148 first IVF/ICSI-cycles and 5-year follow up of frozen embryo replacement (FER) cycles were used. Oocyte number, number of embryos transferred, and cryopreserved/thawed and transferred embryos in a FER cycle were registered for all patients. Children per oocyte and per transferred embryo and percentage of cycles with births were calculated. RESULTS: We obtained 9529 oocytes. Embryos (2507) were transferred in either fresh or FER cycles, resulting in 422 births and 474 live born children. Median age of the women was 32.5 years (range 20-41.5 years). In total, 34.3 % of all cycles ended with a live birth while in 65.7 % of the cycles, no oocytes were capable of developing into a child. The average number of oocytes needed per live born child after transfer of fresh and thawed embryos was 20 as only 5.0 % of oocytes aspirated in the first IVF/ICSI cycle had the competence to develop into a child. CONCLUSIONS: In our setting, overall 5.0 % of the oocytes in a first cycle were biologically competent and in around 2/3 of all cycles, none of the oocytes had the potential to result in the birth of a child.

Birthweight distribution in ART singletons resulting from embryo culture in two different culture media compared with the national population.

STUDY QUESTION: Is there a difference in birthweight distribution in ART singletons born after IVF culture in two different culture media? SUMMARY ANSWER: There is no effect of culture media on both crude and adjusted birthweight distributions in ART singletons from nulliparous mothers. WHAT IS KNOWN ALREADY: Studies on human ART singletons have reported a difference in birthweight in singletons following IVF culture in different culture media. However, other studies comparing different culture media have not shown any significant differences in birthweight. STUDY DESIGN, SIZE, DURATION: This study was a retrospective comparison of birthweights in IVF/ICSI singletons conceived after fresh embryo transfer following embryo culture in Cook or Medicult medium and in a national cohort of naturally conceived singletons in nulliparous women. The study compares four independent groups consisting of singletons in nulliparous women from Cook-d2: 2-day culture in Cook medium at Rigshospitalet (n = 974), Medicult-d2: 2-day culture in Medicult EmbryoAssist medium at Rigshospitalet (n = 147), Medicult-d3: 3-day culture in Medicult EmbryoAssist medium with and without added GM-CSF (n = 204), and DK: pregnancies from the Danish birth registry (n = 106842). PARTICIPANTS/MATERIALS, SETTING, METHODS: The study compares the birthweights of singletons from nulliparous women in the four independent groups mentioned above; Cook-d2: Medicult-d2: Medicult-d3: and DK. In addition, distributions of large and small for gestational age infants were compared between the groups and a multiple linear regression analysis was used to determine which factors determined birthweight. MAIN RESULTS AND THE ROLE OF CHANCE: We found no significant difference in the crude birthweight distributions between singletons born after culture in Cook-d2 or Medicult-groups. Singleton girls from the Cook-d2 group weighed 3302 ± 28 g, versus 3252 ± 76 in the Medicult-d2 group (difference 50 g; P = 0.547). Singleton boys from the Cook-d2 group weighed 3430 ± 27 g, versus 3354 ± 56 in the Medicult-d2 group (difference 76 g; P = 0.279). In the background population, mean birthweights for singleton girls and boys were 3383 ± 2.4 g and 3494 ± 2.5 g, respectively. The mean birthweights of girls, 3315 ± 61 g, and boys, 3383 ± 64 g, in the Medicult-d3 group were not significantly different from that in the Medicult-d2 group. When pooling data from all culture media groups, we found the same slightly lower mean birthweight in IVF/ICSI singletons when compared with the national birth cohort as has been previously reported (Cook-d2 + Medicult-d2 + d3 versus birth cohort; girls: P < 0.001, boys: P < 0.001). We also pooled data on boys and girls and calculated the mean birthweight for the Cook-d2, Medicult-d2 and Medicult-d3 groups and found no significant differences. LIMITATIONS, REASONS FOR CAUTION: The retrospective design and the inherent risk of confounding factors is a limitation. Selection bias cannot be excluded as the embryos cultured in Cook-d2 and Medicult-d2 were from single centre studies while data in Medicult-D3 group were derived from a multicentre study. WIDER IMPLICATIONS OF THE FINDINGS: This large cohort of singletons born after IVF/ICSI shows no difference in crude mean birthweight after culture in two different culture media, indicating that if such a difference exists, this must be specific for certain culture media. As expected we found a slightly lower mean birthweight in ART compared with naturally conceived singletons. This suggests that parental characteristics or IVF technique related factors other than type of culture medium may influence the birthweight in ART singletons. STUDY FUNDING/COMPETING INTERESTS: No external funding was used for this study. No conflicts of interest are declared.

Syncytin-1 and its receptor is present in human gametes.

MAIN PURPOSE AND RESEARCH QUESTION: To determine whether the true fusogen Syncytin-1 and its receptor (ASCT-2) is present in human gametes using qRT-PCR, immunoblotting and immunofluorescence. METHODS: Donated oocytes and spermatozoa, originating from a fertility center in tertiary referral university hospital, underwent qRT-PCR, immunoblotting and immunofluorescence analyzes. RESULTS: Quantitative RT-PCR of sperm samples from sperm donors showed that syncytin-1 is present in all samples, however, protein levels varied between donors. Syncytin-1 immunoreactivity predominates in the sperm head and around the equatorial segment. The receptor ASCT-2 is expressed in the acrosomal region and in the sperm tail. Moreover, ASCT-2, but not syncytin-1, is expressed in oocytes and the mRNA level increases with increasing maturity of the oocytes. CONCLUSIONS: Syncytin and its receptor are present in human gametes and localization and temporal appearance is consistent with a possible role in fusion between oocyte and sperm.

Kinetic markers of human embryo quality using time-lapse recordings of IVF/ICSI-fertilized oocytes.

A time-lapse system was used to study the timing and coordination of events during early development from zygote to cleavage stage embryo. The aim was to identify markers linked to good-quality embryos and implantation. A total of 102 fertilized oocytes were followed for 20-24 h. Events such as appearance and disappearance of (pro)nuclei and timing and synchronization of cell cleavage were logged as time points after fertilization. Averages for these events and their synchrony were calculated and linked with fertilization method, embryo quality and implantation success. Fertilized oocytes that developed into > or =4-cell embryos had an earlier pronuclei disappearance and first cleavage than those that developed to 3- or 2-cell embryos. Intracytoplasmic sperm injection-fertilized 4-cell embryos spent a significantly shorter period as 2-cell compared with IVF-fertilized embryos (P = 0.0090). Development in the time-lapse system was similar to their siblings cultured in normal incubators, suggesting that the data from the time-lapse system can be extrapolated to the clinic's laboratory setting. Early disappearance of pronuclei and onset of first cleavage after fertilization was correlated with a higher number of blastomeres on day 2 after oocyte retrieval. In addition, synchrony in appearance of nuclei after the first cleavage was significantly associated with pregnancy success (P < 0.05).

Nuclei size in relation to nuclear status and aneuploidy rate for 13 chromosomes in donated four cells embryos.

PURPOSE: The aim was to elucidate if the nuclear size and number are indicative of aberrant chromosome content in human blastomeres and embryos. METHODS: The number of nuclei and the nucleus and blastomere size were measured by a computer controlled system for multilevel analysis. Then the nuclei were enumerated for 13 chromosomes by a combination of PNA and DNA probes. RESULTS: In the mononucleated embryos there was no difference in the mean size of chromosomally normal and abnormal nuclei but a significant difference in the mean nuclei size of nuclei that had gained chromosomes compared to nuclei that had lost chromosomes. The nuclei from multinucleated blastomeres had a significant smaller mean size and the frequency of chromosomally aberrant blastomeres was significantly higher. CONCLUSION: The mean nuclear size is not a marker for the chromosome content in mononucleated embryos. However, it seems that the nuclei size can be related to multinucleation and maybe to the chromosome content.

Biochemical pregnancy after fertilization of an oocyte aspirated from a heterotopic autotransplant of cryopreserved ovarian tissue: case report.

Autotransplantation of frozen/thawed ovarian tissue in women undergoing cancer therapy has so far led to the birth of two healthy babies. In both cases, it can be discussed whether the fertilized oocyte originated from the transplant or from the native ovary. We now present a biochemical pregnancy achieved after heterotopical autotransplantation of cryopreserved ovarian cortical tissue and hence the unquestionable proof that pregnancy can occur after transplantation of cryopreserved ovarian tissue. A woman diagnosed with Hodgkin's lymphoma had ovarian tissue cryopreserved at the age of 28, before receiving chemotherapy and radiation therapy that rendered her amenorrhoeic. After complete remission, she had autotransplantation of ovarian tissue to the remaining ovary, to the right pelvic wall and to a midline subperitoneal pocket on the lower abdominal wall. The transplanted tissue resumed hormone secretion and follicles developed in all three locations. Three times during 8 months, when follicles could not be visualized in other locations, oocytes were aspirated from the subperitoneal autotransplanted tissue on the lower abdominal wall. Twice, an oocyte was retrieved, fertilized by intracytoplasmatic sperm injection (ICSI) and transferred to the woman's uterus. One of the treatments resulted in a positive pregnancy test 14 days after transfer. Clinical pregnancy, however, was not achieved. In conclusion, heterotopic autotransplantation of cryopreserved ovarian tissue can sustain follicle development. The oocytes of aspirated mature follicles are capable of fertilization after ICSI, and the resulting embryo is competent of producing hCG at detectable levels.

Sequential FISH analysis using competitive displacement of labelled peptide nucleic acid probes for eight chromosomes in human blastomeres.

BACKGROUND: The aim was to introduce a new strategy based on peptide nucleic acid (PNA) probes and competitive displacement for using fluorescence in-situ hybridization (FISH) analysis on human blastomeres. METHODS: Sequential FISH analysis with PNA probes and competitive displacement was performed using three different probe sets. The first set consisted of labelled probe only. The second and third sets included labelled as well as unlabelled probe, corresponding to the labelled probes in the previous cycles. The probes for enumeration were for chromosome 1, 13, 16, 17, 18, 21, X and Y. RESULTS: The performance of PNA probes was similar to the established DNA probes. The strategy of competitive displacement resulted in a destabilization of already bound probe before the next FISH cycle at only 50 degrees C, which allowed for up to five sequential FISH cycles without loss of signal. CONCLUSIONS: PNA probes are a good alternative to DNA probes in the present set-up, since the low temperature required both for binding and destabilization of PNA probes minimizes the loss of signal, and several FISH cycles can therefore be carried out before FISH errors occur.

Impact of recombinant FSH dose adjustments on ovarian response in the second treatment cycle with IVF or ICSI in "standard" patients treated with 150 IU/day during the first cycle.

BACKGROUND: A dose of 150 IU/day of recombinant follicle stimulating hormone (rFSH) is commonly used as a "standard" dose for "standard" patients in the first in vitro fertilization (IVF) treatment cycle. In the second cycle, the starting dose is adjusted in those patients who had an inappropriate response during the first cycle. The purpose of the study was to assess the impact of dose adjustments on ovarian response. MATERIALS AND METHODS: Retrospective study including 567 first IVF/intracytoplasmic sperm injection (ICSI) cycles using the long agonist protocol in "standard" patients. In the second cycle 385 patients who had failed to achieve an ongoing pregnancy were included. The starting dose in the second cycle was adjusted according to the response in the first cycle. RESULTS: A total of 215 patients (55.8%) had altered starting dose in the second cycle: 193 (50.1%) received >150 IU/day, whereas 22 (5.7%) had <150 IU/day. In the group given >150 IU/day, significantly more follicles (9.8 vs. 8.3, p = 0.002) and oocytes (8.4 vs. 6.7, p <0.0001) were obtained in the second cycle. In the group given <150 IU/day, there were significantly fewer follicles (20.4 vs. 13.5, p <0.0001) and oocytes (16.4 vs. 11.4, p = 0.005) in the second cycle. In the group given <150 IU/day in the second cycle, six (27.3%) had an appropriate ovarian response (5-14 oocytes) in the first cycle compared to 14 (63.6%) women in the second cycle (p = 0.01). The ongoing pregnancy rates in all of the first (32.1%) and second cycles (27%) were similar (p = NS). CONCLUSION: In a "standard" patient population, 55.8% needed an altered starting dose in the second cycle and rFSH dose adjustments had a significant impact on the ovarian response.

Embryo quality in natural versus stimulated IVF cycles.

BACKGROUND: The impact of controlled ovarian stimulation (COS) on oocyte and subsequent embryo quality remains controversial. In the present study we have compared embryo quality in natural and stimulated cycles in the same group of patients. METHODS: This retrospective study was comprised of patients with a regular menstrual cycle who had IVF after COS using rFSH in a long GnRH agonist protocol. In all stimulated cycles the patients had fresh embryos transferred and surplus good quality embryos cryopreserved. Subsequently the same patients were treated with a modified FER cycle (mFER) where thawing of the frozen embryos was combined with aspiration of the dominant follicle in the natural cycle. The embryo cleavage stage and quality score were compared between the stimulated and the natural cycle for the patients having an embryo in the natural cycle. RESULTS: In 177 cases patients returned for mFER in a natural cycle. Spontaneous ovulation had occurred in 35 cycles. In 17 cycles no oocyte was retrieved at aspiration and in 125 cycles 128 oocytes were aspirated. In the stimulated cycles from these patients we had obtained 950 embryos (cleavage rate 70.4%) versus 85 embryos (cleavage rate 66.4%) (P = 0.34) in the natural cycles. Comparing the embryos in the natural and stimulated cycles in all patients having an embryo in the natural cycle, we found no difference in the distribution between the different cleavage stages. Of the cleaved embryos, 53% in the stimulated cycles had >or=4 cells versus 59% in the natural cycles after 2 days culture (P = 0.31). In the stimulated cycles 61% of the embryos had <10% fragmentation at the time of transfer on day 2, compared to 69% in the natural cycles (P = 0.15). CONCLUSION: The administration of exogenous gonadotrophins was not reflected in cleavage capacity or quality assessment of the resulting embryos.

FISH analysis for chromosomes 13, 16, 18, 21, 22, X and Y in all blastomeres of IVF pre-embryos from 144 randomly selected donated human oocytes and impact on pre-embryo morphology.

BACKGROUND: The data are compiled from two multicentre, prospectively randomized studies on the effect of follicular fluid meiosis-activating sterol (FF-MAS) on human oocytes. The donated oocytes were exposed either to test doses of FF-MAS or to control solutions. The data from the control groups are presented with chromosomal status of the embryos correlated to embryo morphology. METHODS: The study includes 144 randomly selected donated human oocytes. The nucleus from each blastomere was fixed separately and fluorescence in-situ hybridization (FISH) using seven probes (13, 16, 18, 21, 22, X and Y) was performed. RESULTS: Analysis of 103 pre-embryos containing 479 blastomeres resulted in 424 blastomeres with clear FISH signals. Of these blastomeres, 55% were normal diploid and 45% were abnormal. At a pre-embryonic level, 53% were classified as normal containing >or=50% normal blastomeres while 31% of the pre-embryos were classified as uniformly normal. Abnormality rate was significantly increased in the pre-embryos with unevenly sized blastomeres and with increasing degree of fragmentation at 68 h after fertilization. Applying criteria for good embryo quality significantly increased the rate of chromosomally normal pre-embryos from 53 to 75%. CONCLUSIONS: The data demonstrate the high degree of genetic heterogeneity in a randomly selected pool of donated pre-embryos from an IVF programme. Further, we found that uniformity of blastomere size, degree of fragmentation and cleavage kinetics reflect the cytogenetic status of the pre-embryo and are therefore important in the selection of pre-embryos.

Progesterone supplementation during early gestations after IVF or ICSI has no effect on the delivery rates: a randomized controlled trial.

BACKGROUND: The aim was to study whether prolongation of luteal support during early pregnancy influences the delivery rate after IVF. METHODS: Dual centre study including 303 women who achieved pregnancy after IVF or ICSI was used. All were treated with the long protocol using GnRH agonists and given luteal support with 200 mg vaginal progesterone three times daily during 14 days from the day of transfer until the day of a positive HCG test. The study group (n = 150) withdrew vaginal progesterone from the day of positive HCG. The control group (n = 153) continued administration of vaginal progesterone during the next 3 weeks of pregnancy. RESULTS: The number of miscarriages prior to and after week 7 of gestation was seven (4.6%) and 15 (10.0%) in the study group and five (3.3%) and 13 (8.5%) in the control group respectively. The number of deliveries was 118 (78.7 %) in the study group and 126 (82.4 %) in the control group. The differences were not significant. CONCLUSIONS: Prolongation of progesterone supplementation in early pregnancy has no influence on the miscarriage rate, and thus no effect on the delivery rate. Progesterone supplementation can safely be withdrawn at the time of a positive HCG test.

Time to pregnancy in relation to semen quality assessed by CASA before and after sperm separation.

BACKGROUND: In order to provide a reference for infertile men, we defined normal values of semen quality in a population of fertile men, using computer-assisted semen analysis (CASA) before and after sperm separation. Additionally, we investigated the relationship between semen quality and time to pregnancy (TTP). METHODS AND RESULTS: Semen samples were obtained from 315 proven fertile men. The median sperm concentration in fresh samples was 107 x 10(6)/ml (5-95 percentiles: 16-322 x 10(6)/ml), the median percentage of motile sperm cells was 65% (14-87%) and the median percentage of progressively motile cells was 37% (5-64%). After density gradient sperm separation, the median total sperm count was 46 x 10(6) (4-350 x 10(6)), the median percentage of motile sperm cells was 77% (16-95%) and the median percentage of progressively motile cells was 63% (11-84%). No significant associations were found between TTP and sperm counts or sperm motility, either before or after sperm separation. This may be due in part to the fact that the study comprised couples with proven fertility. CONCLUSION: We have defined semen parameters, including the results of density gradient separation, in a population of normal fertile men which may be of interest in the evaluation of semen samples from infertile men.

Single intragenic microsatellite preimplantation genetic diagnosis for cystic fibrosis provides positive allele identification of all CFTR genotypes for informative couples.

This study is part of a strategy aimed at using fluorescent polymerase chain reaction (PCR) on informative genetic microsatellite markers as a diagnostic tool in preimplantation genetic diagnosis (PGD) of severe monogenic disease. Two couples, both of whom had previously had children who were compound heterozygote for severe cystic fibrosis mutations, were offered PGD using fluorescent PCR of the highly polymorphic cystic fibrosis transmembrane conductance regulator (CFTR) intragenic microsatellite marker IVS17bTA. Cleavage-stage embryo biopsy followed by PCR resulted in transfer of one unaffected carrier embryo for each couple. This approach eliminates the need for single cell multiplex PCR strategies to detect CF compound heterozygotes. It also provides a control of chromosome 7 ploidy in the blastomeres and a selection against allele dropout by positive detection of each CFTR copy of all genotypes in preimplantation embryos from genetically informative families.

Embryo quality and developmental potential is compromised by age.

AIMS: The aim of this retrospective study was to assess whether and how the age of the woman affects the quality and developmental potential of the oocytes and embryos in an ART program. METHOD AND MATERIAL: A total of 878 IVF cycles was included as a consecutive series of single transfers (n=292), dual transfers (n=366) and triple transfers (n=220), where all the transferred embryos in each cycle were of identical quality score and identical cleavage stage. RESULTS: We found a highly significant decrease in oocyte recovery with increasing age with about one oocyte per 2.3 years (95% CI 1.8 years to 3.1 years, p<0.0001). Further, we found that the number of oocytes that cleaved declined significantly with increasing age with one per 3.7 years (95% CI 2.7 years to 5.5 years, p<0.0001). This decline was mainly due to the decline in number of oocytes retrieved as the ratio of aspirated oocytes that cleaved with increasing age (approx. -0.04/10 year 95% CI: -0.10; +0.009) was not significantly different (p=0.10). The percentage of transfers using fragmented embryos did not increase significantly with increasing age (p=0.08). The odds of fragmentation increased by 3% per year. The average number of embryos transferred decreased significantly (p=0.03) with age from approximately 2.1 at the age of 25 to approximately 1.8 at the age of 40. In a selected subgroup of embryos all consisting of good quality embryos, a significant decrease was found in implantation rate with increasing age (approx. -0.08/10 years, 95% CI: -1.6; +0.00, p=0.05). Of the 357 pregnancies achieved in this study we found a significantly decreased ongoing pregnancy rate and a significantly increased abortion rate with increasing age (p=0.03). The decrease in the rate of ongoing pregnancies was almost linear, decreasing by approximately 1.5% per year. CONCLUSIONS: We conclude that age has an impact throughout a woman's reproductive life and that it is important to realize that the age-related decline in fertility may start already in the late twenties and not in the mid-thirties as is generally assumed.

Progesterone supplementation during early gestation after in vitro fertilization has no effect on the delivery rate.

OBJECTIVE: To compare the delivery rate with IVF or ICSI in women who did and did not receive progesterone supplementation in the first 3 weeks after a positive hCG test result. DESIGN: Retrospective study. SETTING: Fertility Clinic, Rigshospitalet University Hospital, Copenhagen, Denmark. PATIENT(S): 200 pregnant women who did not receive progesterone (intervention group) and 200 pregnant women who received progesterone for 3 weeks after a positive hCG result. INTERVENTION(S): In the study group, vaginal progesterone therapy was withdrawn on the day of positive hCG result. In the control group, treatment with progesterone, 600 mg/d, was continued for 3 weeks after a positive hCG result. Both groups received 600 mg of progesterone starting on the day of embryo replacement until testing positive for pregnancy 14 days after embryo transfer. MAIN OUTCOME MEASURES: Delivery rate. RESULT(S): The number of deliveries was 126 in the study group and 128 in the control group. CONCLUSION(S): The delivery rate was the same in pregnant women who received and those who did not receive progesterone for 3 weeks after a positive hCG result. Progesterone supplementation for more than 2 weeks after embryo transfer may therefore yield no benefit in terms of pregnancy.

[Infertility in ethnic groups. Etiology and treatment]. / Infertilitet hos etniske par. Arsager og behandling.

In this retrospective case control study we analysed the causes and treatments of infertility in 100 ethnic couples consecutively discharged from the Fertility Clinic in the period October 1995 to March 1999. The mean age at referral was 28 years (19-37) for ethnic women and 31 years (24-39) for Danish women. Male infertility was the most frequent cause in ethnic couples compared to Danish couples (24% vs. 16%; NS). Tubal infertility was less frequent in ethnic than in Danish couples (19% vs. 45%; p < 0.01), ovulatory defects were more frequent in ethnic couples than in Danish (13% vs. 4%; p < 0.04). Among ethnic couples 57 (118 cycles) underwent IVF and ICSI treatment vs. 85 (198 cycles) Danish couples (p < 0.01). The ongoing pregnancy rate per initiated cycle was 29.6% in ethnic couples vs. 24.2% in Danish couples (NS). Forty four percent of the ethnic couples did not complete the whole treatment program vs. 29% of Danish couples (p < 0.04). This may be due to cultural differences and difficult communication.

Requirements for human chorionic gonadotropin and recombinant human luteinizing hormone for follicular development and maturation.

PURPOSE: Our purpose was to evaluate the requirements for human chorionic gonadotropin (hCG) and recombinant luteinizing hormone (rec-LH) for follicular development and maturation in mice. METHODS: We carried out ovarian stimulation of immature mice. Output parameters were the preembryos created in vivo and frequency of blastocyst formation in vitro. RESULTS: hCG at 0 to 1 IU resulted in a dose-dependent recovery of preembryos (0 to 39.7 +/- 4.3; mean +/- SE) per mouse. hCG at 1 and 10 hCG gave similar results, whereas higher doses significantly reduced the number of preembryos. Potential for blastocyst formation was independent of hCG dose. hCG and rec-LH together exerted a synergistic effect on the recovery of preembryos. CONCLUSIONS: Optimal follicular development required a combination of 20 IU follicle stimulating hormone and 1-10 IU hCG. The potency of hCG was higher than that of rec-LH, but a synergistic effect of rec-LH and hCG was observed. The results may be pertinent for the development of strategies for ovarian stimulation of women with low levels of endogenous LH.

A Danish national cohort of 730 infants born after intracytoplasmic sperm injection (ICSI) 1994-1997.

This national cohort study included all clinical pregnancies obtained after intracytoplasmic sperm injection (ICSI) registered in Denmark between January 1994 and July 1997 at five public and eight private fertility clinics. Laboratory and clinical data were obtained from the fertility clinics. The couples answered a questionnaire regarding the pregnancy and the health of the child (response rate 94%). Data validation was carried out through discharge charts. The mean age of the women was 32.1 years. In 84.2% of couples, male factor was the main reason for performing ICSI, and in 4.8% epididymal spermatozoa were used. The mean number of embryos replaced was 2.3 (range 1-3) and in 95% of cases fresh embryos were transferred. Only 183 women (28.5%) underwent prenatal diagnosis, resulting in 209 karyotypes with seven (3.3%) chromosome aberrations. Six major chromosomal abnormalities (2.9%) and one inherited structural chromosome aberration (0.5%) were found, but no sex chromosome aberrations. The frequency of multiple birth, Caesarean section rate, gestational age, preterm birth, and birth weight were comparable with previous studies. The perinatal mortality rate was 13.7 per 1000 children born with a gestational age of 24 weeks or more. In 2.2% (n = 16) of the liveborn infants, and in 2.7% (n = 20) of all infants, major birth defects were reported by the parents. Minor birth defects were found in nine liveborn infants (1.2%). In conclusion, the results of this study on outcome of ICSI pregnancies are in line with earlier reports, except that no sex chromosome abnormalities were found.