Thalita Berteli

• PhD
• Senior Embryologist at Kofinas Fertility Group

Background The number of re-biopsied blastocysts is widely increasing in PGT cycles and concerns regarding retesting, which involve double biopsy and vitrification-warming, have been raised. The re-biopsy intervention seems to significantly reduce the pregnancy potential of a blastocyst but the evidence is still restricted to retrospective observat...

Abstract Purpose Long interspersed nuclear element-1 (LINE-1 or L1) comprises 17% of the human genome. Retrotransposons may perturb gene integrity or alter gene expression by altering regulatory regions in the genome. The germline employs a number of mechanisms, including cytosine methylation, to repress retrotransposon transcription throughout mos...

Research question: Is the membrane lipid profile of mice blastocysts affected by ovarian stimulation, IVF and oocyte vitrification? Could supplementation of vitrification media with L-carnitine and fatty acids prevent membrane phospholipid changes in blastocysts from vitrified oocytes? Design: Experimental study comparing the lipid profile of mu...

Oocyte vitrification is a widespread and well-established assisted reproduction technique that has enabled some patient groups to obtain clinical results equivalent to those using fresh oocytes. However, as the number of babies born from vitrified oocytes has increased, so has the discussion regarding the method’s safety for the offspring. Cryogeni...

Research question : Can the exposure time to equilibration solutions during oocyte vitrification affect the lipid profile of oocytes and embryonic development? Could vitrification media supplemented with oleic and linoleic acids, and L-carnitine (LC) be effective to minimize damage induced by vitrification on embryo development and oocyte membrane...

Background The number of re-biopsied blastocysts is widely increasing in IVF cycles and concerns regarding retesting, which involves double biopsy and vitrification-warming, have been raised. The re-biopsy intervention seems to significantly reduce the pregnancy potential of a blastocyst but the evidence is still restricted to retrospective observa...

Purpose Unlike other cells in the body, in sperm, telomere length (TL) increases with age. TL can regulate nearby genes, and the subtelomeric region is rich in retrotransposons. We hypothesized that age-related telomere lengthening in sperm might suppress Long Interspersed Element 1 (LINE-1/L1), the only competent retrotransposon in humans. Method...

Objective Millions of babies have been conceived by IVF, yet debate about its safety to offspring continues. We hypothesized that superovulation and in vitro fertilization (IVF) promote genomic changes, including altered telomere length (TL) and activation of the retrotransposon LINE-1 (L1), and tested this hypothesis in a mouse model. Material an...

Purpose Millions of pregnant, HIV-infected women take reverse transcriptase inhibitors, such as zidovudine (azidothymidine or AZT), during pregnancy. Reverse transcription plays important roles in early development, including regulation of telomere length (TL) and activity of transposable elements (TE). So we evaluated the effects of AZT on embryo...

Objective: Millions of babies have been conceived by IVF, yet debate about its safety to offspring continues. We hypothesized that superovulation and in vitro fertilization (IVF) promote genomic changes, including altered telomere length (TL) and activation of the retrotransposon LINE-1 (L1), and tested this hypothesis in a mouse model. Material an...

Study question Do human sperm contain novel LINE–1 insertions and are they affected by paternal age? Summary answer Human sperm contain novel LINE–1 insertions. Their location or number are not affected by paternal age. What is known already LINE–1 comprises 17% of the human genome and some LINE–1s are the only autonomous retrotransposons in huma...

Purpose Millions of pregnant, HIV-infected women take reverse transcriptase inhibitors, such as zidovudine (AZT), during pregnancy. Reverse transcription plays important roles in early development, including regulation of telomere length (TL) and activity of transposable elements (TE). So we evaluated the effects of AZT on embryo development, TL, a...

STUDY QUESTION: Do human sperm contain novel LINE-1 insertions and are they affected by paternal age? SUMMARY ANSWER: Human sperm contain novel LINE-1 insertions. Their location or number are not affected by paternal age. WHAT IS KNOWN ALREADY: LINE-1 comprises 17% of the human genome and some LINE-1s are the only autonomous retrotransposons in hum...

Maintenance of genome integrity in the germline and in preimplantation embryos is crucial for mammalian development. Epigenetic remodeling during primordial germ cell (PGC) and preimplantation embryo development may contribute to genomic instability in these cells, since DNA methylation is an important mechanism to silence retrotransposons. Long in...

Telomeres, repetitive sequences and associated proteins which cap and protect chromosome ends, undergo attrition with age in most tissues, providing an aging clock. Unlike other tissues, sperm telomeres increase rather than decrease with paternal age. The function of age-related sperm telomere elongation remains poorly understood. In yeast, mice an...

OBJECTIVE: In order to obtain a stable glassy state in the vitrification process, it is necessary to combine high cooling rates, small volumes of highly concentrated cryoprotectant solutions and short exposure times. During equilibration phase of oocyte vitrification, the exposure time varies from 10 to 15 minutes according to manufacturers' recomm...

OBJECTIVE: Volumetric damages and cytotoxicity due to cryoprotectants exposure are time-sensitive in the vitrification technique and can trigger a lipid remodeling of the plasma membrane. How equilibration step changes abundance and composition of different lipid classes remain largely unknown. Here we investigate the impact of the exposure time to...

OBJECTIVE: To investigate the impact of oocyte vitrification on lipid profile of mice blastocysts by comparing blastocysts originated from fresh and from vitrified oocytes subjected to in vitro fertilization. Also, to assess the effects of supplementing the vitrification media with antioxidants and unsaturated fatty acids by comparing blastocysts v...

OBJECTIVE: To evaluate the impact of ovarian stimulation (OS) and OS plus in vitro fertilization (IVF) procedure on lipid profile of mice blastocysts by comparing the lipid profile of blastocysts originated from natural mating with or without previous superovulation and blastocysts from oocytes of superovulated females subject to IVF. DESIGN: Exper...

Even the strictest laboratories and clinics are prone to the occurrence of microbial contamination. In the case of in vitro fertilization (IVF) research and practice facilities, the number of possible sources is particularly vast. In addition to ambient air, personnel, and non-sterilized materials, follicular fluid and semen from patients are a ver...

Zika virus (ZIKV) is mainly transmitted through Aedes mosquito bites, but sexual and post-transfusion transmissions have been reported. During acute infection, ZIKV is detectable in most organs and body fluids including human semen. Although it is not currently epidemic, there is a concern that the virus can still reemerge since the male genital tr...

Since the advent of IVF in 1978, many novel techniques have arisen in Assisted Human Reproduction (AR). Every year thousands of people seek treatment, with success rates ranging from 35% to 40%. The way of assessing an embryo for intrauterine transfer is still carried out by means of morphological parameters, a traditional methodology that brings l...

A resposta ao estímulo ovariano é uma peça‐chave na reprodução assistida. Apesar dos recentes avanços das técnicas, pacientes com baixa reserva ovariana apresentam mau prognóstico e representam um desafio na medicina reprodutiva.