Further delineation of the rare GDACCF (global developmental delay, absent or hypoplastic corpus callosum, dysmorphic facies syndrome): genotype and phenotype of 22 patients with ZNF148 mutations.

BACKGROUND: Pathogenic variants in the zinc finger protein coding genes are rare causes of intellectual disability and congenital malformations. Mutations in the ZNF148 gene causing GDACCF syndrome (global developmental delay, absent or hypoplastic corpus callosum, dysmorphic facies; MIM #617260) have been reported in five individuals so far. METHODS: As a result of an international collaboration using GeneMatcher Phenome Central Repository and personal communications, here we describe the clinical and molecular genetic characteristics of 22 previously unreported individuals. RESULTS: The core clinical phenotype is characterised by developmental delay particularly in the domain of speech development, postnatal growth retardation, microcephaly and facial dysmorphism. Corpus callosum abnormalities appear less frequently than suggested by previous observations. The identified mutations concerned nonsense or frameshift variants that were mainly located in the last exon of the ZNF148 gene. Heterozygous deletion including the entire ZNF148 gene was found in only one case. Most mutations occurred de novo, but were inherited from an affected parent in two families. CONCLUSION: The GDACCF syndrome is clinically diverse, and a genotype-first approach, that is, exome sequencing is recommended for establishing a genetic diagnosis rather than a phenotype-first approach. However, the syndrome may be suspected based on some recurrent, recognisable features. Corpus callosum anomalies were not as constant as previously suggested, we therefore recommend to replace the term 'GDACCF syndrome' with 'ZNF148-related neurodevelopmental disorder'.

Perinatal outcomes in singletons after fresh IVF/ICSI: results of two cohorts and the birth registry.

RESEARCH QUESTION: How are perinatal outcomes of live-born singletons after stimulated and unstimulated IVF different from perinatal outcomes in (i) children born in a tertiary centre and (ii) all children born in Switzerland? METHODS: This cohort study compared the perinatal outcomes of two birth cohorts and the national live birth registry. Relative risks were calculated using modified Poisson regression and clustering for siblings and adjustment for maternal age, parity and childs sex. RESULTS: Of the 636,639 live births, 311 were in the Bern IVF Cohort (144 stimulated, 167 unstimulated), 2332 in the tertiary centre and 633,996 in the Swiss Live Birth Registry (SLBR). Perinatal outcomes following IVF did not differ compared with births in the SLBR (adjusted relative risk [aRR]; 95% confidence interval [CI]), with the exception of the increased risk of small for gestational age (1.31; 1.01 to 1.70, P = 0.04; aRR 1.12; 0.87 to 1.45, P = 0.39). Children born following stimulated IVF had a higher risk of low birthweight (2.17; 1.27 to 3.69, P < 0.01; aRR 1.72; 1.01 to 2.93, P = 0.05), and of being small for gestational age (1.50; 1.05 to 2.14, P = 0.03; aRR 1.31; 0.92 to 1.87; P = 0.13), whereas children born after unstimulated IVF had no increased risks compared with the SLBR. Higher Caesarean rate after IVF was mainly associated with higher maternal age. CONCLUSION: Singletons in the Bern IVF Cohort do not show less favourable perinatal outcomes. Gonadotrophin stimulation seems to have an effect, because lower risks were associated with unstimulated IVF.

The greater incidence of small-for-gestational-age newborns after gonadotropin-stimulated in vitro fertilization with a supraphysiological estradiol level on ovulation trigger day.

INTRODUCTION: Reproductive scientists have postulated various risk factors for lower birthweight following conventional gonadotropin-stimulated in vitro fertilization compared with spontaneously conceived children: parental factors (age, health, duration of subfertility and smoking habits); ovarian stimulation; laboratory procedures; the number of oocytes retrieved and the number of embryos transferred. Our aim was to investigate the impact of gonadotropin stimulation and serum estradiol level on the risk of a newborn being small-for-gestational-age. MATERIAL AND METHODS: We conducted a cohort study (2010-2016) of singletons (n = 155) born either after conventional gonadotropin-stimulated in vitro fertilization (using ≥150 IU/d human gonadotropin for stimulation) or after natural cycle in vitro fertilization without any stimulation. We analyzed perinatal outcomes using birthweight percentiles, adjusted for gestational age and sex. RESULTS: The proportion of small-for-gestational-age was 11.8% following conventional gonadotropin-stimulated in vitro fertilization and 2.9% after natural cycle in vitro fertilization (P = 0.058). The odds of small-for-gestational-age were significantly higher with supraphysiological estradiol levels in maternal serum on ovulation trigger day (unadjusted odds ratio 4.58; 95% confidence interval 1.35-15.55; P = 0.015). It remained significant after adjusting for maternal height, age and body mass index (adjusted odds ratio 3.83; 95% confidence interval 1.06-13.82; P = 0.041). CONCLUSIONS: We found an associated risk of children being born small-for-gestational-age after conventional gonadotropin-stimulated in vitro fertilization compared with natural cycle in vitro fertilization. This higher risk is significantly associated with supraphysiological estradiol levels. We propose a reduction in the dosage of gonadotropin to minimize the risk of small-for-gestational-age and future health consequences.