Risk factors associated with preterm birth in singletons born after IVF: a national cohort study

RESEARCH QUESTION

What are the risk factors for prematurity other than intrauterine growth restriction in singletons after IVF?

DESIGN

Data were collected from a national registry, based on an observational prospective cohort of 30,737 live births after assisted reproductive technology (fresh embryo transfers: n = 20,932 and frozen embryo transfer [FET] n = 9805) between 2014 and 2015. A population of not-small for gestational age singletons conceived after fresh embryo transfers and FET, and their parents, was selected. Data on a number of variables were collected, including type of infertility, number of oocytes retrieved and vanishing twins.

RESULTS

Preterm birth occurred in 7.7% (n = 1607) of fresh embryo transfers and 6.2% (n = 611) of frozen-thawed embryo transfers (P < 0.0001; adjusted odds ratio [aOR] = 1.34 [1.21-1.49]). Endometriosis and vanishing twin increased the risk of preterm birth after fresh embryo transfer (P < 0.001; aOR 1.32 and 1.78, respectively). Polycystic ovaries or more than 20 oocytes retrieved also increased preterm birth risk (aOR 1.31 and 1.30; P = 0.003 and P = 0.02, respectively); large oocyte cohort (>20) was no longer associated with the risk of prematurity in FET.

CONCLUSION

Endometriosis remains a risk for prematurity even in the absence of intrauterine growth retardation, which suggests a dysimmune effect. Large oocyte cohorts obtained by stimulation, without clinical polycystic ovary syndrome diagnosed before attempts, do not affect FET outcomes, reinforcing the idea of a phenotypic difference in the clinical presentation of polycystic ovary syndrome.

Fetal growth disorders following medically assisted reproduction: due to maternal context or techniques? A national French cohort study

RESEARCH QUESTION

What part do maternal context and medically assisted reproduction (MAR) techniques play in the risk of fetal growth disorders?

DESIGN

This retrospective nationwide cohort study uses data available in the French National Health System database and focuses on the period from 2013 to 2017. Fetal growth disorders were divided into four groups according to the origin of pregnancy: fresh embryo transfer (n = 45,201), frozen embryo transfer (FET, n = 18,845), intrauterine insemination (IUI, n = 20,179) and natural conceptions (n = 3,412,868). Fetal growth disorders were defined from the percentiles of the weight distribution according to gestational age and sex: small and large for gestational age (SGA and LGA) if <10th and >90th percentiles, respectively. Analyses were performed using univariate and multivariate logistic models.

RESULTS

Compared with births following natural conception, multivariate analysis showed that the risk of SGA was higher for births following fresh embryo transfer and IUI (adjusted odds ratio [aOR] 1.26 [1.22-1.29] and 1.08 [1.03-1.12], respectively) and significantly lower following FET (aOR 0.79 [0.75-0.83]). The risk of LGA was higher for births following FET (aOR 1.32 [1.27-1.38]), especially in artificial cycles when compared with ovulatory cycles (aOR 1.25 [1.15-1.36]). In the subgroup of births without any obstetrical or neonatal morbidity, the same increased risk of SGA and LGA were observed following fresh embryo transfer or IUI and FET (aOR 1.23 [1.19-1.27] or 1.06 [1.01-1.11] and aOR 1.36 [1.30-1.43], respectively).

CONCLUSIONS

An effect of MAR techniques on the risks for SGA and LGA is suggested independently from maternal context and obstetrical or neonatal morbidities. Pathophysiological mechanisms remain poorly understood and should be further evaluated, as well as the influence of embryonic stage and freezing techniques.

What should be done in terms of fertility preservation for patients with cancer? The French 2021 guidelines

AIM

To provide practice guidelines about fertility preservation (FP) in oncology.

METHODS

We selected 400 articles after a PubMed review of the literature (1987-2019).

RECOMMENDATIONS

Any child, adolescent and adult of reproductive age should be informed about the risk of treatment gonadotoxicity. In women, systematically proposed FP counselling between 15 and 38 years of age in case of treatment including bifunctional alkylating agents, above 6 g/m2 cyclophosphamide equivalent dose (CED), and for radiation doses on the ovaries ≥3 Gy. For postmenarchal patients, oocyte cryopreservation after ovarian stimulation is the first-line FP technique. Ovarian tissue cryopreservation should be discussed as a first-line approach in case of treatment with a high gonadotoxic risk, when chemotherapy has already started and in urgent cases. Ovarian transposition is to be discussed prior to pelvic radiotherapy involving a high risk of premature ovarian failure. For prepubertal girls, ovarian tissue cryopreservation should be proposed in the case of treatment with a high gonadotoxic risk. In pubertal males, sperm cryopreservation must be systematically offered to any male who is to undergo cancer treatment, regardless of toxicity. Testicular tissue cryopreservation must be proposed in males unable to cryopreserve sperm who are to undergo a treatment with intermediate or severe risk of gonadotoxicity. In prepubertal boys, testicular tissue preservation is: - recommended for chemotherapy with a CED ≥7500 mg/m2 or radiotherapy ≥3 Gy on both testicles. - proposed for chemotherapy with a CED ≥5.000 mg/m2 or radiotherapy ≥2 Gy. If several possible strategies, the ultimate choice is made by the patient.

Obstetrical outcomes and maternal morbidities associated with COVID-19 in pregnant women in France: A national retrospective cohort study

BACKGROUND

To the best of our knowledge, no study has exhaustively evaluated the association between maternal morbidities and Coronavirus Disease 2019 (COVID-19) during the first wave of the pandemic in pregnant women. We investigated, in natural conceptions and assisted reproductive technique (ART) pregnancies, whether maternal morbidities were more frequent in pregnant women with COVID-19 diagnosis compared to pregnant women without COVID-19 diagnosis during the first wave of the COVID-19 pandemic.

METHODS AND FINDINGS

We conducted a retrospective analysis of prospectively collected data in a national cohort of all hospitalizations for births ≥22 weeks of gestation in France from January to June 2020 using the French national hospitalization database (PMSI). Pregnant women with COVID-19 were identified if they had been recorded in the database using the ICD-10 (International Classification of Disease) code for presence of a hospitalization for COVID-19. A total of 244,645 births were included, of which 874 (0.36%) in the COVID-19 group. Maternal morbidities and adverse obstetrical outcomes among those with or without COVID-19 were analyzed with a multivariable logistic regression model adjusted on patient characteristics. Among pregnant women, older age (31.1 (±5.9) years old versus 30.5 (±5.4) years old, respectively, p < 0.001), obesity (0.7% versus 0.3%, respectively, p < 0.001), multiple pregnancy (0.7% versus 0.4%, respectively, p < 0.001), and history of hypertension (0.9% versus 0.3%, respectively, p < 0.001) were more frequent with COVID-19 diagnosis. Active smoking (0.2% versus 0.4%, respectively, p < 0.001) and primiparity (0.3% versus 0.4%, respectively, p < 0.03) were less frequent with COVID-19 diagnosis. Frequency of ART conception was not different between those with and without COVID-19 diagnosis (p = 0.28). When compared to the non-COVID-19 group, women in the COVID-19 group had a higher frequency of admission to ICU (5.9% versus 0.1%, p < 0.001), mortality (0.2% versus 0.005%, p < 0.001), preeclampsia/eclampsia (4.8% versus 2.2%, p < 0.001), gestational hypertension (2.3% versus 1.3%, p < 0.03), postpartum hemorrhage (10.0% versus 5.7%, p < 0.001), preterm birth at <37 weeks of gestation (16.7% versus 7.1%, p < 0.001), <32 weeks of gestation (2.2% versus 0.8%, p < 0.001), <28 weeks of gestation (2.4% versus 0.8%, p < 0.001), induced preterm birth (5.4% versus 1.4%, p < 0.001), spontaneous preterm birth (11.3% versus 5.7%, p < 0.001), fetal distress (33.0% versus 26.0%, p < 0.001), and cesarean section (33.0% versus 20.2%, p < 0.001). Rates of pregnancy terminations ≥22 weeks of gestation, stillbirths, gestational diabetes, placenta praevia, and placenta abruption were not significantly different between the COVID-19 and non-COVID-19 groups. The number of venous thromboembolic events was too low to perform statistical analysis. A limitation of this study relies in the possibility that asymptomatic infected women were not systematically detected.

CONCLUSIONS

We observed an increased frequency of pregnant women with maternal morbidities and diagnosis of COVID-19 compared to pregnant women without COVID-19. It appears essential to be aware of this, notably in populations at known risk of developing a more severe form of infection or obstetrical morbidities and in order for obstetrical units to better inform pregnant women and provide the best care. Although causality cannot be determined from these associations, these results may be in line with recent recommendations in favor of vaccination for pregnant women.

Do in vitro fertilization, intrauterine insemination or female infertility impact the risk of congenital anomalies in singletons? A longitudinal national French study

STUDY QUESTION

Do IVF, IUI or female infertility (i.e. endometriosis, polycystic ovary syndrome [PCOS] and primary ovarian insufficiency [POI]) lead to an increased risk of congenital anomalies in singletons?

SUMMARY ANSWER

After multivariable adjustments, the increased risks of congenital defects associated with IUI were no longer significant, but the underlying maternal infertility presented a potential emental risk, in addition to the risk associated with IVF.

WHAT IS KNOWN ALREADY

Most epidemiological studies suggest that singletons born from ART have a higher risk of birth defects, specifically musculoskeletal, cardiovascular and urogenital disorders. However, most of these studies were established on data obtained at birth or in the neonatal period and from relatively small populations or several registries. Moreover, to our knowledge, female infertility, which is a potential confounder, has never been included in the risk assessment.

STUDY DESIGN, SIZE, DURATION

Using data from the French National Health System database, we conducted a comparative analysis of all singleton births (deliveries ≥22 weeks of gestation and/or >500 g of birthweight) in France over a 5-year period (2013-2017) resulting from fresh embryo or frozen embryo transfer (fresh-ET or FET from IVF/ICSI cycles), IUI and natural conception (NC). Data were available for this cohort of children at least up to early childhood (2.5 years old).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 3 501 495 singleton births were included (3 417 089 from NC, 20 218 from IUI, 45 303 from fresh-ET and 18 885 from FET). Data were extracted from national health databases and used to identify major birth defects. Malformations were classified according to the 10th revision of the International Classification of Disease. To analyse the effect of mode of conception, multivariable analyses were performed with multiple logistic regression models adjusted for maternal age, primiparity, obesity, smoking, history of high blood pressure or diabetes and female infertility.

MAIN RESULTS AND THE ROLE OF CHANCE

In our cohort of children, the overall prevalence of congenital malformations was 3.78% after NC, 4.53% after fresh-ET, 4.39% after FET and 3.91% after IUI (132 646 children with major malformations). Compared with infants conceived naturally, children born after fresh-ET and after FET had a significantly higher prevalence of malformations, with an adjusted odds ratio (aOR) of 1.15 [95% CI 1.10-1.20, P < 0.0001] and aOR of 1.13 [95% CI 1.05-1.21, P = 0.001], respectively. Among the 15 relevant subgroups of malformations studied, we observed a significantly increased risk of eight malformations in the fresh-ET group compared with the NC group (i.e. musculoskeletal, cardiac, urinary, digestive, neurological, cleft lip and/or palate and respiratory). In the FET group, this increased risk was observed for digestive and facial malformations. The overall risk of congenital malformations, and the risk by subtype, was similar in the IUI group and the NC group (overall risk: aOR of 1.01 [95% CI 0.94-1.08, P = 0.81]). In addition, there was an overall independent increase in the risk of congenital defects when the mothers were diagnosed with endometriosis (1.16 aOR [95% CI 1.10-1.22], P < 0.0001), PCOS (1.20 aOR [95% CI 1.08-1.34], P = 0.001) or POI (1.52 aOR [95% CI 1.23-1.88], P = 0.0001). Chromosomal, cardiac and neurological anomalies were more common in the three maternal infertility groups.

LIMITATIONS, REASONS FOR CAUTION

Male infertility, the in vitro fertilization method (i.e. in vitro fertilization without or with sperm injection: conventional IVF vs ICSI) and embryo stage at transfer could not be taken into account. Furthermore, residual confounding cannot be excluded as well as uncertainties regarding the diagnostic criteria used for the three female infertilities. Findings for specific malformations should be interpreted with caution because the number of cases was small in some sub-groups (potentially due to the Type I error or multiple testing).

WIDER IMPLICATIONS OF THE FINDINGS

In this large study, after multivariable maternal adjustments, a moderately increased risk of defects subsisted after IVF, while those associated with IUI were no longer significant. In addition, our results showed that underlying maternal infertility could contribute to the increased risk of defects associated with IVF. These novel findings highlight the importance of taking into account the ART treatment methods and the type of infertility.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Agency of Biomedicine. The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

NA.

Endometriosis and assisted reproductive techniques independently related to mother-child morbidities: a French longitudinal national study

RESEARCH QUESTION

Does endometriosis increase obstetric and neonatal complications, and does assisted reproductive technology (ART) cause additional risk of maternal or fetal morbidity?

DESIGN

A nationwide cohort study (2013-2018) comparing maternal and perinatal morbidities in three groups of single pregnancies: spontaneous pregnancies without endometriosis; spontaneous pregnancies with endometriosis; and ART pregnancies in women with endometriosis.

RESULTS

Mean maternal ages were 30.0 (SD = 5.3), 31.7 (SD = 4.8) and 33.1 years (SD = 4.0), for spontaneous conceptions, spontaneous conceptions with endometriosis and ART pregnancies with endometriosis groups, respectively (P < 0.0001). Comparison of spontaneous conceptions with endometriosis and spontaneous conceptions: endometriosis independently increased the risk of venous thrombosis (adjusted OR [aOR] 1.51, P < 0.001), pre-eclampsia (aOR 1.29, P < 0.001), placenta previa (aOR 2.62, P < 0.001), placental abruption (aOR 1.54, P < 0.001), premature birth (aOR 1.37, P < 0.001), small for gestational age (aOR 1.05, P < 0.001) and malformations (aOR 1.06, P = 0.049). Comparison of ART pregnancies with endometriosis and spontaneous conceptions with endometriosis: ART increased the risk of placenta previa (aOR 2.43, 95% CI 2.10 to 2.82, P < 0.001), premature birth (aOR 1.42, 95% CI 1.29 to 1.55, P < 0.001) and small for gestational age (aOR 1.18, 95% CI 1.10 to 1.27, P < 0.001), independently from the effect of endometriosis. Risk of pre-eclampsia, placental abruption or congenital malformations was not increased with ART.

CONCLUSION

Endometriosis is an independent risk factor for mother and child morbidities. Maternal morbidity and perinatal morbidity were significantly increased by ART in addition to endometriosis; however, some perinatal and maternal morbidity risks were increasingly linked to pathologies related to infertility.

Disparities in reproductive outcomes according to the endometrial preparation protocol in frozen embryo transfer : The risk of early pregnancy loss in frozen embryo transfer cycles

PURPOSE

The purpose of this study was to determine the effect of stimulated and artificial endometrial preparation protocols on reproductive outcomes in frozen embryo transfer (FET) cycles.

METHODS

We performed a retrospective study of 1926 FET cycles over a 3.5-year period in the Fertility Unit at a University Hospital. Stimulated and artificial protocols were used for endometrial preparation. The embryos for FET were obtained from either in vitro fertilization or intracytoplasmic sperm injection cycles. Live birth rate and early pregnancy loss rates were retrospectively compared. In artificial protocols, oral or vaginal administration of oestradiol 2 mg two or three times a day was followed by vaginal supplementation with progesterone 200 mg two or three times a day. In stimulated protocols, recombinant follicle-stimulating hormone was administered from day 4 onward. Vaginal ultrasound was used for endometrial and ovarian monitoring. A pregnancy test was performed 14 days after FET. If it was positive, oestradiol and progesterone were administered up until the 12th week of gestation in artificial cycles. We defined early pregnancy losses as biochemical pregnancies (preclinical losses) and miscarriages.

RESULTS

Data on 865 artificial cycles (45% of the total) and 1061 stimulated cycles (55%) were collected. Early pregnancy loss rate was significantly lower for stimulated cycles (34.2%) than for artificial cycles (56.9%), and the live birth rate was significantly higher for stimulated cycles (59.7%) than for artificial cycles (29.1%).

CONCLUSION

In frozen embryo transfer, artificial cycles were associated with more early pregnancy loss and lower live birth rate than stimulated cycles.

Soluble HLA-G in IVF/ICSI embryo culture supernatants does not always predict implantation success: a multicentre study

Several reports have described an association between the presence of soluble human leukocyte antigen G (sHLA-G) in human embryo culture supernatants (ES) and implantation success. However, not all studies agree with these findings. To further document this debate, a multicentre blinded study was performed to investigate, on a large number of IVF ES and ICSI ES, whether sHLA-G is a useful criterion for embryo selection before transfer. A total of 1405 ES from 355 patients were collected from three assisted reproductive technique (ART) centres and evaluated for their sHLA-G content in a single laboratory, using a chemiluminescence enzyme-linked immunosorbent assay. In only one centre was a significant association between sHLA-G-positive ES and successful implantation established (P = 0.0379), whereas no such association was observed in the other centres. It was found that the percentages and concentrations of sHLA-G-positive ES varied between centres, depending on culture media and ART conditions. The percentage of sHLA-G-positive ES was significantly higher in IVF ES than ICSI ES (P < 0.001 and P < 0.01 for two centres). These data demonstrate that substantial variations of sHLA-G content in ES occur between different ART centres, highlighting the influence of several technical parameters that differ from one centre to another.

Paternité tardive : aspects spermatiques et génétiques

The effect of maternal age on the risk of meiotic abnormality is well documented. In contrast little is known about the effect of the paternal age. The question of the risk related to paternal age is raised because of the increased demand of Assisted Reproduction Techniques for older men. This review focuses on the alterations of male semen parameters, testis histology and genetic risks related to age. The motility, vitality and morphology of spermatozoa and semen volume are found decreasing with age. Histomorphometric studies reveal various alterations including a thickening of the basal membrane when spermatogenesis is arrested. The number of germinal and Sertoli cells decreases with increased age. Up to 95 years old, we could find subjects with complete spermatogenesis. Chromosomal analyses in different studies have provided controversial results. Our investigation on subjects aged from 29 to 102 showed that the rate of aneuploidy in the group of aged subjects with preserved spermatogenesis was not statistically different from the young control group. However the incidence of postmeiotic aneuploidy was increased when spermiogenesis had stopped. On the other hand from epidemiological studies, autosomal dominant diseases are known to be associated with paternal age. However, in the case of achondroplasia and Apert syndrome, direct DNA sperm analysis did not reveal significant increase in the mutation frequency with paternal age.

Influence du vieillissement sur la spermatogenèse : évaluation histologique, risque chromosomique et apoptose des spermatozoïdes

OBJECTIVE

The increase of frequency of Assisted Reproductive Techniques (ART) for elder men raises the question of the genetic risk for the offspring. Our aim was to evaluate the influence of ageing on the testicular histology, the aneuploidy rate in testis postmeiotic cells and the DNA fragmentation in sperm.

PATIENTS AND METHODS

We performed a histomorphometric study of 36 men aged from 61 to 102 years and 10 young men from 29 to 40 years. The aneuploidy rate was evaluated by fluorescent in situ hybridation (FISH X, Y, 18) and DNA fragmentation in spermatozoa was evaluated by TUNEL.

RESULTS

Histomorphometry showed various alterations of testicular histology with age including thickening of the basal membrane when spermatogenesis was arrested. The number of germinal cells and Sertoli cells decreased with age with important individual variations. Nevertheless spermatogenesis could be possible until 95 years. The rate of aneuploidy was not influenced by age when spermatogenesis was complete. However, we observed an increased aneuploidy rate in postmeiotic cells when spermiogenesis was arrested. On the other hand apoptosis was not increased with age.

DISCUSSION AND CONCLUSION

Our study confirms that spermatogenesis is possible until a very advanced age (95 years) without any specific chromosome risk. The question of mutagenesis remains to be solved.

Influence of the number of motile spermatozoa inseminated and of their morphology on the success of intrauterine insemination

BACKGROUND

Although intrauterine insemination (IUI) is one of the most common assisted reproductive technology methods in the world, the relative influence of various semen characteristics on the likelihood of a successful outcome is controversial. The aim of our study was to assess the results of IUI as a function of both the number of motile spermatozoa inseminated (NMSI) and the percentage of morphologically normal spermatozoa after preparation.

METHODS

This was a retrospective study of 889 couples who underwent 2564 IUI cycles of ovarian stimulation with HMG or recombinant FSH in our centre between January 1991 and December 2000.

RESULTS

A total of 331 clinical pregnancies were obtained, for a pregnancy rate/cycle of 12.91%. When the NMSI was < 1 x 10(6), the pregnancy rate/cycle was significantly lower (3.13%) than in any of the subgroups with NMSI > or = 2 x 10(6). Sperm morphology, assessed before or after preparation, was not in itself a significant factor that affected the likelihood of IUI success. Nonetheless, when the post-migration rate of normal sperm was < 30%, the pregnancy rate/cycle was 5.43% when NMSI was < 5 x 10(6) and 18.42% when NMSI was > or = 5 x 10(6) (P = 0.008). Pregnancy rates did not differ significantly according to NMSI when the percentage of normal sperm after preparation was > or = 30%, or according to percentage of normal sperm when the NMSI was > or = 5 x 10(6).

CONCLUSIONS

Our results show that a minimum of 5 x 10(6) motile spermatozoa should be inseminated when the normal morphology of the sperm after preparation is < 30%; the quantity compensates at least in part for the defective quality. If this threshold of NMSI cannot be obtained, IVF should be recommended.

Biopsied testis cells of four 47,XXY patients: fluorescence in-situ hybridization and ICSI results

BACKGROUND

A testis biopsy was performed for four non-mosaic 47,XXY azoospermic patients. Spermatozoa were found in three cases and frozen before ICSI. We analysed the various cells found in the four samples by multicolour fluorescence in-situ hybridization (FISH), to evaluate the meiosis and spermatogenesis possibilities of the 47,XXY and 46,XY testis cell lines, and to estimate aneuploidy rate in the resulting spermatids and spermatozoa.

METHODS AND RESULTS

Testis diploid cells (either somatic or premeiotic), meiotic, and post-meiotic haploid germ cells were hybridized with probes for chromosomes X, Y and 18. The only patient with no spermatozoa had a homogeneous diploid XXY constitution in the testis; the three other patients presented two cell populations (46,XY and 47,XXY) among their diploid testis cells. All the observed pachytene figures were XY; no XXY pachytene figure was found. The aneuploidy rate among post-meiotic cells for chromosomes X,Y and 18 was 6.75% (5/74). This rate was 1.5% (2/133) for control. Three couples underwent ICSI; four attempts were made, one healthy baby was born.

CONCLUSION

FISH results suggest that only 46,XY cells can undergo meiosis.

An idiopathic infertility with oocytes metaphase I maturation block: case report

BACKGROUND

A case of idiopathic primary infertility was attributed to a block in oocyte meiosis affecting the transition between metaphase I and metaphase II.

METHODS AND RESULTS

A couple suffering unexplained primary infertility was unsuccessfully treated by various means of assisted reproductive technology. After four unsuccessful pregnancy attempts using intrauterine inseminations (IUI), IVF was attempted (all oocytes remained unfertilized), followed by an ICSI cycle. None of the retrieved oocytes expelled the polar body, and therefore were not injected. The failure of these assisted reproduction cycles was, in both cases, due to the immaturity of the oocytes recovered. Cytogenetic analysis of the oocytes retrieved for ICSI provided evidence of meiotic arrest. Using cytogenetic staging criteria we were able to show that this arrest occurred between metaphase I and anaphase I.

CONCLUSIONS

Meiotic blocks affecting oocytes have already been described for various mammals. We discuss here mechanisms that might be involved in this possibly inherited disorder in humans, and ways in which our knowledge of them could be increased.

Chromosome 21 detection in human oocyte fluorescence in situ hybridization: possible effect of maternal age

PURPOSE

The purpose of this study was to evaluate, among 100 uncleaved oocytes, the incidence of numerical and structural chromosome 21 and X abnormalities and to analyze the influence of various factors, such as in vitro (IVF) indications, follicle stimulation protocols, and women's age.

METHODS

We investigated 150 uncleaved oocytes from 128 patients after an IVF attempt. After cytogenetic analysis (Giemsa) 100 oocytes (66%) were selected for fluorescence in situ hybridization (FISH). Fluorescent probes for human chromosomes X and 21 were used simultaneously according to standard procedures for their hybridization and detection.

RESULTS AND CONCLUSIONS

We analyzed by the FISH protocol 100 metaphase II oocytes with 22 to 25 chromosomes. Our results demonstrate a high rate of disomy for chromosome 21 in human oocytes. Among them, eight were disomic (8%) and three were nullosomic (3%) for chromosome 21. Only one disomy of chromosome X was noted. The various indications of IVF and the different folliculogenesis stimulating protocols did not seem to influence the results but suggested a correlation between the maternal age and the aneuploidy rate of chromosome 21.

Incidence of AZF (azoospermia factor) deletions and familial forms of infertility among patients requiring intracytoplasmic spermatozoa injection (ICSI)

PURPOSE

The aim of our study was to determine the incidence of AZF deletions and familial forms of infertility suggesting autosomal mutations among patients requiring intracytoplasmic sperm injection with ejaculated sperm.

METHODS

Cases with obstructive pathologies were excluded; 81 patients were classified according to the numeration of spermatozoa. The distribution was as follows: 10 cases with normal numeration (greater than 20 million/ml) (group 1), 10 cases with between 10 and 20 million/ml (group 2), 6 cases with between 5 and 10 million/ml (group 3), 15 cases with between 1 and 5 million/ml (group 4), 29 cases with less than 1 million/ml (group 5), and 11 azoospermic patients (group 6). The infertility of 11 of the 81 patients might be explained by testicular ectopy.

RESULTS

We found two deletions limited to the AZFc region among our 81 infertile patients--one deletion in group 5 and one deletion in group 4 (both groups of oligozoospermic patients)--and no deletion in the groups with normal or subnormal numerations. We found six familial forms of infertility. We did not find any AZF deletion, neither in these 6 patients nor in the 11 with testicular ectopy. The identification of these families of infertile men will allow research of autosomal genes involved in male infertilities.

CONCLUSIONS

It is important to test deletions of the AZFc region for oligozoospermic patients, and familial forms of infertility do not seem to concern the same individuals.

[Intracytoplasmic injection of spermatozoa]

Management of male infertility has been totally changed with the development of intracytoplasmic sperm injection (ICSI). This technique, used for in vitro fertilization, consists in injecting a single spermatozoa into the ovum. Intracytoplasmic sperm injection can be proposed in case of severe male sterility (oligoasthenospermia) or after repeated failure of in vitro fertilization. Satisfactory rates of fecondation and pregnancy have been obtained. Results have also been obtained with sperm taken from the epididymis or testis. The risks involved concern the transmission of poorly understood genetic defects leading to the infertility. The rates of reported malformations and chromosome anomalies are quite low. Intracytoplasmic sperm injection can be useful in managing most cases of male infertility which to date have had to rely on donor sperm. Long-term results have not yet been obtained.

[Cytogenetic analysis of human oocytes after sperm microinjection]

After standard in vitro fertilization (IVF) chromosome analysis of uncleaved oocytes has shown that in about 80% of the cases, there was no fertilization at all while in 10% of the cases there was a premature chromosome condensation and a development arrest. After micro-injection our results suggest that both the technique itself and the pathologies which require micro-injection can influence the results. On the other hand about 20-30% of the metaphase II oocytes are cytogenetically abnormal after IVF attempt while ICSI might increase chromosome breakage. Our results suggest that both the technique used and the gamete pathologies can influence the different steps of development arrest.

Cytogenetic analysis of uncleaved oocytes after intracytoplasmic sperm injection

PURPOSE

This work analyzes the causes of cleavage failure after intracytoplasmic sperm injection (ICSI) and the effect of the procedure on the chromosomes of the oocytes.

METHODS

Ninety-seven uncleaved oocytes from 39 patients with severe male infertility or repeated IVF failure were fixed; 79 were analyzable. We checked the decondensation stage of spermatozoa nucleus and the chromosomal abnormalities of the oocytes.

RESULTS

Among the fixed oocytes, the spermatozoa nucleus was present in 97% of the cases, and it was undecondensed in 89% of the cases, showing no evolution at all. A low rate (2.6%) of premature chromosome condensation (PCC) of the spermatozoa and a low rate (2.5%) of female diploïdy were observed. Among the oocytes that could be karyotyped, we observed a high rate (45%) of chromosome breakage.

CONCLUSION

ICSI fertilization failure was due mostly to the complete lack of evolution of the spermatozoa nucleus. Oocyte selection before ICSI seemed to lower the PCC rate. The high rate of oocyte chromosomal breakage rate has to be confirmed.

[Are desquamated trophoblastic cells retrieved from the cervix suitable for a prenatal diagnosis?]

Prenatal diagnosis based on sampling of fetal tissues, amniotic fluid or chorionic villi is associated with the risk of miscarriage and fetal damage. These risks would be avoided if diagnosis could be performed in desquamated trophoblast cells recovered non-invasively from the maternal cervix. We report on our experience of fetal karyotyping on endocervical lavage using in situ hybridization (FISH) and DNA amplification (PCR) fetal sex was correctly predicted in 8/10 cases by FISH and in 6/10 by PCR. FISH appeared to be a reliable technique for karyotyping when trophoblast can be recovered from the maternal endocervix (8/10).