S. Desmyttere

Report on a consecutive series of 581 children born after blastomere biopsy for preimplantation genetic diagnosis

BACKGROUND Preimplantation genetic diagnosis (PGD) and subsequently preimplantation genetic screening (PGS) have been introduced since 1990. The difference from the already existing in vitro fertilization (IVF) technology, using intracytoplasmic sperm injection (ICSI), was the embryo biopsy at day 3 after fertilization. Although healthy children post-PGD/PGS have been born, the question of whether embryo biopsy could have any harmful effects has to be studied on large series in a prospective manner. METHODS A prospective cohort study was undertaken from 1992 until 2005, using the same approach as for the follow-up of IVF and ICSI children conceived in the same centre. Questionnaires were sent to physicians and parents at conception and at delivery. Children were examined at 2 months of age by trained clinical geneticists whenever possible. RESULTS Data collected on 581 post-PGD/PGS children showed that term, birthweight and major malformation rates were not statistically different from that of 2889 ICSI children, with overall rates of major malformation among these post-PGD/PGS and ICSI children being 2.13 and 3.38%, respectively (odds ratio [OR]: 0.62; exact 95% confidence limits [95% CL]: 0.31-1.15). However, the overall perinatal death rate was significantly higher among post-PGD/PGS children compared with ICSI children (4.64 versus 1.87%; OR: 2.56; 95% CL: 1.54-4.18). When stratified for multiple births, perinatal death rates among PGD/PGS singleton and ICSI singleton children were similar (1.03 versus 1.30%; OR: 0.83; 95% CL: 0.28-2.44), but significantly more perinatal deaths were seen in post-PGD/PGS multiple pregnancies compared with ICSI multiple pregnancies (11.73 versus 2.54%; OR: 5.09; 95% CL: 2.80-9.90). The overall misdiagnosis rate was below 1%. CONCLUSIONS Embryo biopsy does not add risk factors to the health of singleton children born after PGD or PGS. The perinatal death rate in multiple pregnancies is such that both caution and long-term follow-up are required.

Clinical application of preimplantation diagnosis for myotonic dystrophy

Myotonic dystrophy (DM) or Steinerts disease is a progressive autosomal dominant disease characterized by increasing muscle weakness, myotonia, cataracts, and endocrine abnormalities such as diabetes and testicular atrophy. The gene for DM was cloned in 1992 and the mutation was shown to be an expanded trinucleotide (CTG) repeat. A polymerase chain reaction (PCR)‐based assay was described soon after that would allow (prenatal) diagnosis of the disease. Based on these PCR assays, we have developed a method for carrying out single‐cell PCR for DM. In preimplantation diagnosis, embryos obtained in vitro are checked for the presence or absence of a disease, after which only embryos shown to be free of the disease under consideration are returned to the mother. A single‐cell assay was developed for preimplantation diagnosis in couples where one of the parents is afflicted with DM. Twenty intracytoplasmic sperm injection (ICSI) cycles were carried out in eight patients and between one and four embryos were replaced in 17 out of 20 cycles. Two of the patients became pregnant and have had prenatal diagnosis which has confirmed that they are unaffected.

Mental and psychomotor development of 2-year-old children born after preimplantation genetic diagnosis/screening

BACKGROUND Embryo biopsy is a new invasive procedure applied in ART for diagnostic purposes in preimplantation genetic diagnosis (PGD) or to increase pregnancy rate in preimplantation genetic screening (PGS). The objective of this study is to assess mental and psychomotor developmental outcomes in 2-year-old children born after PGD/PGS, intracytoplasmic sperm injection (ICSI) and natural conception (NC). METHODS Two-year-old PGD/PGS (n = 70), ICSI (n = 70) and naturally conceived (n = 70) singleton children were recruited. The participation rate in the NC group was 88.6% and 94.5% in both ART conception groups. The mental and psychomotor development of the children was assessed using the Dutch version of the Bayley Scales of Infant Development. The mothers were questioned about socio-demographic characteristics. RESULTS Even after controlling for socio-demographic variables, no differences were found between the three conception groups for the mental and psychomotor developmental outcomes. Moreover, an equal number of PGD/PGS, ICSI and NC children obtained scores within the mildly delayed, the normal and the accelerated performance category of the BSID-II-NL. CONCLUSIONS Children conceived after PGD/PGS show similar mental and psychomotor developmental outcomes at age 2 to children conceived after ICSI or naturally.

Neonatal follow-up of 995 consecutively born children after embryo biopsy for PGD

BACKGROUND Outcome data on children born after assisted reproduction treatments are important for both patients and health-care providers. The objective of this study was to determine whether embryo biopsy as performed in PGD has an impact on the health of infants up to 2 months of age. METHODS A prospective comparative follow-up study of children born after PGD and children born after ICSI by collecting written reports and performing a physical examination at 2 months was performed. Auxological data at birth and physical findings up to 2 months of age were compared for 995 children consecutively live born after embryo biopsy (1994-2009) and for a control group of 1507 children born after ICSI with embryo transfer on Day 5. RESULTS No differences regarding mean term, prematurity (term <32 w and <37 w), mean birthweight, very low birthweight (<1500 g), perinatal death, major malformations and neonatal hospitalizations in singletons and multiples born following PGD versus ICSI were observed. Compared with ICSI, fewer multiples born following PGD presented a low birthweight (<2500 g) (P = 0.005). CONCLUSIONS Embryo biopsy for PGD does not introduce extra risk to the overall medical condition of newborn children. Multiples born following embryo biopsy appear to be at lower risk for low birthweight compared with multiples born following ICSI.

Socio-emotional and language development of 2-year-old children born after PGD/PGS, and parental well-being

BACKGROUND The objective of this study was to assess socio-emotional and language development in 2-year-old children born after preimplantation genetic diagnosis (PGD) and genetic aneuploidy screening (PGS), intracytoplasmic sperm injection (ICSI) and natural conception (NC) and to assess parental well-being. METHODS Parents of 2-year-old PGD/PGS (n = 41), ICSI (n = 35) and NC (n = 53) singleton children were recruited. The socio-emotional development of the children was assessed using the Child Behavioural Checklist (CBCL) and the Short Temperament Scale for Toddlers. Parental stress and health status was measured with the Parent Stress Index and the General Health Questionnaire. Language development was assessed with the McArthur Communicative Development Inventories. RESULTS No differences were found for temperament, language development, parental stress or health status. The mothers in the PGD/PGS and ICSI group reported significantly fewer CBCL Total problems than their NC counterparts, whereas for the CBCL Externalizing problems, only the ICSI mothers reported fewer problems than their PGD/PGS and NC counterparts. Fathers in the ICSI group also rated their children as having fewer Externalizing and Total behavioural problems. CONCLUSIONS PGD/PGS conception does not adversely affect childrens socio-emotional and language development at age 2, nor did parents differ from ICSI and NC parents for parental stress and health status.

Growth and health outcome of 102 2-year-old children conceived after preimplantation genetic diagnosis or screening.

OBJECTIVE The major objective of this study was to determine whether the embryo biopsy procedure might cause growth restriction or affect health outcome of children. STUDY DESIGN Auxological data and physical findings were compared at birth and age 2 for 102 children (70 singletons and 32 twins) born after PGD/PGS and 102 matched children born after intracytoplasmic sperm injection (ICSI) in a prospective study. RESULTS No statistically significant differences regarding weight, height and head circumference standard deviation scores (SDS) at birth and at age two years were observed. At two years of age the mean BMI SDS tended to be lower in PGD/PGS children (p=0.058). PGD/PGS babies had been more often breastfed (p=0.013), but mostly during a shorter time. The prevalence of major as well as minor congenital anomalies, hospital admissions and surgical interventions was similar. CONCLUSION Children born after embryo biopsy applied in PGD/PGS present similar prenatal and postnatal growth and health outcome in the first two years of life compared to ICSI children. Up till now, PGD and PGS appear not to be associated with a higher risk for health problems.

Cognitive and psychomotor development of 5- to 6-year-old singletons born after PGD: a prospective case–controlled matched study

STUDY QUESTION Do preschool preimplantation genetic diagnosis (PGD) children differ in their cognitive and psychomotor development from children born after ICSI and spontaneous conception (SC)? SUMMARY ANSWER The cognitive development of PGD pre-schoolers was comparable to children born after ICSI and SC but motor development differed between ICSI and SC groups. STUDY DESIGN, SIZE DURATION The cognitive abilities and motor skills of 5- to 6-year-old singletons born after PGD (n = 47) were assessed in comparison with 49 ICSI and 48 SC children in a prospective, case-controlled, matched follow-up study between April 2011 and May 2013. PARTICIPANTS/MATERIALS, SETTING, METHODS PGD singletons, ICSI and SC children of preschool age were examined with the Wechsler Preschool and Primary Scale of Intelligence (WPSSI-III-NL) and the Movement ABC (M ABC). The WPSSI-III-NL revealed scores for Full IQ, Verbal IQ and Performance IQ. The M ABC yields a total score and comprising scores for measurements of balance, dexterity and ball skills. Since embryo biopsy is the only technical difference between the PGD and ICSI procedures, ICSI children were included as controls. These children were part of a Dutch-speaking cohort of children conceived after assisted reproduction technology (ART) at the Universitair Ziekenhuis Brussel (UZ Brussel) who received longitudinal follow-up. The SC children acted as a second control group similar to the fertile PGD sample and in contrast to the ICSI group. The SC group was recruited through announcements in a variety of media. The children were matched for age, gender, birth order and educational level of the mother. The assessments carried out for the ART groups were blinded whenever possible. The data were analysed using analysis of covariance (ANCOVA) and partial eta squared (η(2)), which was used as a measurement of effect size. MAIN RESULTS AND THE ROLE OF CHANCE The overall cognitive development of PGD singletons did not differ from controls [P = 0.647, η(2) = 0.006; 95% confidence interval (CI) (0, 0.043)]. The partial IQ scores for Verbal and Performance intelligence revealed similar results. Analysis of motor development based on the total score as well as subscales did indicate a significant difference between the three conception groups [P = 0.033, η(2) = 0.050, 95% CI (0, 0.124)]. Post hoc analysis indicated that the significant difference was situated between performances of ICSI and SC children. Balance capacities [P = 0.004, η(2) = 0.079, 95% CI (0.025, 0.163)] and its post hoc analysis yielded equivalent results. Motor capacities of PGD singletons, however, did not differ from any of the two other conception groups. LIMITATIONS, REASONS FOR CAUTION Given that we only assessed Caucasian singletons born after PGD, caution is required when drawing more general inferences from our results. The small sample size may be a limitation. A priori power analysis, however, revealed that at least 52 children per group were needed to detect a medium effect and 80% power using ANCOVA. Originally our sample met this threshold but we had to exclude six cases in order to remove outliers and due to missing data. WIDER IMPLICATIONS OF THE FINDINGS Long-term follow-up of children born after embryo biopsy, in this case for PGD, is needed to confirm that the development of these children remains comparable to ICSI and SC children. Our findings do support the safety of the PGD technique and will reassure patients with hereditary genetic diseases regarding the health of their future offspring conceived with PGD. STUDY FUNDING/COMPETING INTERESTS Funding for this study was obtained from the OZR (Research group of the Vrije Universiteit Brussel), the FWO (Fonds Wetenschappelijk Onderzoek) and the Wetenschappelijk Fonds Willy Gepts. The UZ Brussel and the Centre of Medical Genetics received funding from pharmaceutical firms for data collection. UZ Brussel and the Centre for Medical Genetics have received many educational grants for organizing the data collection, from IBSA, Ferring, Organon, Shering-Plough, Merck and Merck Belgium. M.B. has received consultancy and speakers fees from Organon, Serono Symposia and Merck.

The incidence of monozygotic twinning following PGD is not increased

BACKGROUND Monozygotic (MZ) twin pregnancies are associated with increased perinatal mortality and morbidity, and risk of congenital anomalies. The causes of MZ twinning in humans are unclear but the incidence may increase after PGD, for example, as a result of holes created in the zona pellucida. We compared the incidence of MZ twin pregnancies in ICSI cycles with PGD, versus ICSI cycles without PGD. METHODS In this retrospective comparative cohort study, we analysed incidence of twin pregnancies in unselected patients undergoing ICSI and PGD (group A; 1992 cycles) with blastocyst transfer at Day 5, versus a period-matched control population of unselected patients undergoing ICSI and blastocyst transfer at Day 5 without PGD (group B; 2429 cycles) from January 2001 to December 2006. RESULTS Clinical pregnancy per embryo transfer was established in 618/1992 (31.0%) and 947/2429 (39.0%) in group A versus B, respectively (P < 0.01). Overall MZ twin rate was 29/4421 (0.7%) per embryo transfer and 29/1565 (1.9%) per established clinical pregnancy. The incidence of MZ twinning per established clinical pregnancy did not differ between groups (1.5 versus 2.1%, group A and B, respectively). In group A, seven MZ twins were born versus 19 MZ twins in group B. In group B, one MZ twin pregnancy resulted in two stillbirths. In group A, two MZ twins had severe congenital malformations versus none in group B. CONCLUSIONS The incidence of MZ twinning was not increased in PGD compared with regular ICSI with blastocyst transfer. This information is useful in counselling patients about potential risks of PGD.

Preimplantation genetic diagnosis for myotonic dystrophy type 1: upon request to child

Preimplantation genetic diagnosis (PGD) is an alternative to prenatal diagnosis for patients at risk of transmitting an inherited disease such as myotonic dystrophy type 1(DM1) to their offspring. In this paper, the clinical application of preimplantation diagnosis for DM1 upon request to children born is described in a large cohort of risk couples. PGD could be offered to all 78 couples opting for PGD regardless of the triplet repeat size. The incidence of major complications was minimalised following a careful assessment in affected DM1 females anticipating possible cardiological, obstetrical and anaesthetical problems. A live-birth delivery rate per cycle with oocyte retrieval of 20% was the outcome. Forty-eight of the 49 children born are in good health and have normal psychomotor development.

Psychosocial development of full term singletons, born after preimplantation genetic diagnosis (PGD) at preschool age and family functioning: a prospective case-controlled study and multi-informant approach

STUDY QUESTION Do full term singletons born after preimplantation genetic diagnosis (PGD) differ in their psychosocial functioning from children born after intracytoplasmic sperm injection (ICSI) and spontaneous conceived controls (SC)? SUMMARY ANSWER The psychosocial maturation process of 5-6-year-old PGD children is comparable between the three conception groups (PGD, ICSI and SC). WHAT IS ALREADY KNOWN In general, a lot of research has been published regarding follow-up of children born after artificial reproductive technologies (ART), which mainly is reassuring. But the ART population itself is marked by broad diversity [IVF, ICSI, gamete donation, preimplantation genetic screening (PGS) or PGD] which complicates comparisons. Some literature concerning the socio-emotional development of PGD/PGS children is available and it suggests a normal maturation process. However, the complex reality of PGD families (e.g. safety of the technique and psychological burden of genetic histories) asks for an exclusive PGD sample with matched control groups and a multi-informant approach. STUDY DESIGN, SIZE, DURATION Between April 2011 and May 2013, the psychosocial wellbeing of preschoolers and their families born after PGD was assessed in a prospective case-controlled, matched follow-up study, with a multi-informant approach. PARTICIPANTS/MATERIALS, SETTING, METHODS A group of 47 PGD, 50 ICSI and 55 SC 5-6-year-old children participated in a follow-up study performed at the Centre for Medical Genetics of the Universitair Ziekenhuis Brussel (UZ Brussel). Assessments took place in the hospital and in kindergartens. Children performed the Bene-Anthony family relations test (FRT), yielding their perceptions upon family relationships. Parents and teachers completed the child behaviour checklist (CBCL) and Caregiver Teacher Report Form (C-/TRF), respectively. Parental and family functioning were measured by the NEO-FFi, the parenting stress index (PSI), the Greenberger Work-Parenting Investment Questionnaire and the Marlowe-Crowne Social Desirability Scale (MCSDS). Statistical analysis was performed by using analysis of covariance (ANCOVA). MAIN RESULTS AND THE ROLE OF CHANCE No differences were detected between the psychosocial development of PGD children and the control groups. Parents did not differ in reporting problem behaviour and they were stricter than teachers. Concerning family functioning the ART parents scored comparable with each other. PGD and ICSI mothers were emotionally more stable [NEO-FFi Neuroticism/emotionality: P = 0.013, η(2) = 0.066; 95% confidence interval (CI) 95% (0.003;0.148)]. They experienced less parental stress in general [PSI, Total stress: P = 0.001, η(2) = 0.102, 95% CI (0.02;0.192)] and on different sublevels opposed to their SC counterparts. Yet ART mothers presented higher ratings on the NEO-FFi Conscientiousness [P = 0.011, η(2) = 0.064; 95% CI (0.003;0.144)] indicating a higher feeling of competence and goal directedness. Mediation analysis confirmed: PGD and ICSI mothers who experienced less family stress were emotionally more stable. A power analysis indicated that a sample with 152 children is sufficient to detect a medium size effect with 80% power using ANCOVA. LIMITATIONS, REASONS FOR CAUTION The current sample comprised only Dutch speaking Caucasians, hence conclusions should be drawn cautiously. Future research should include larger groups, prematures, multiples and children from different cultural backgrounds. WIDER IMPLICATIONS OF THE FINDINGS This current research is the first to compare PGD preschoolers with matched controls. Concerns about the behavioural effects on the offspring should not inhibit the use of PGD. Furthermore, our findings suggest that on the long run ART procedures might enhance personal resources of women to cope with family stress. These findings are reassuring for women who might feel insecure and anxious during their ART trajectory. STUDY FUNDING/COMPETING INTERESTS This research project gained funding from the OZR (a grant by the Research group of the Vrije Universiteit Brussel), the FWO (Fonds Wetenschappelijk Onderzoek) and the Wetenschappelijk Fonds Willy Gepts. The UZ Brussel and the Centre of Medical Genetics received funding from pharmaceutical firms for data collection. UZ Brussel and the Centre for Medical Genetics have received many educational grants for organizing the data collection, from IBSA, Ferring, Organon, Shering-Plough, Merck and Merck Belgium. M.B. has received consultancy and speakers fees from Organon, Serono Symposia and Merck. The other authors have no competing interests. TRIAL REGISTRATION NUMBER not applicable.