Nikolaos F. Vlahos

Dr. Nikolaos F. Vlahos


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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MPMichail Papapanou
Michail Papapanou
MPMaria Papaioannou
Maria Papaioannou
APAikaterini Petta
Aikaterini Petta
EREleni Routsi
Eleni Routsi
MFMaria Farmaki
Maria Farmaki
Charalampos SiristatidisCharalampos Siristatidis
Charalampos Siristatidis
(1) Background: A considerable number of systematic reviews, with substantial heterogeneity regarding their methods and included populations, on the impact of COVID-19 on infected pregnant women and their neonates, has emerged. The aim was to describe the obstetric-perinatal and neonatal outcome of infected pregnant women and their newborns during the COVID-19 pandemic; (2) Methods: Three bibliographical databases were searched (last search: 10 September 2020). Quality assessment was performed using the AMSTAR-2 tool. Primary outcomes included mode of delivery, preterm delivery/labor, premature rupture of membranes (PROM/pPROM) and abortions/miscarriages. Outcomes were mainly presented as ranges. A separate analysis, including only moderate and high-quality systematic reviews, was also conducted. The protocol was registered with PROSPERO (CRD42020214447); (3) Results: Thirty-nine reviews were analyzed. Reported rates, regarding both preterm and term gestations, varied between 52.3 and 95.8% for cesarean sections; 4.2–44.7% for vaginal deliveries; 14.3–63.8% specifically for preterm deliveries and 22.7–32.2% for preterm labor; 5.3–12.7% for PROM and 6.4–16.1% for pPROM. Maternal anxiety for potential fetal infection contributed to abortion decisions, while SARS-CoV-2-related miscarriages could not be excluded. Maternal ICU admission and mechanical ventilation rates were 3–28.5% and 1.4–12%, respectively. Maternal mortality rate was <2%, while stillbirth, neonatal ICU admission and mortality rates were <2.5%, 3.1–76.9% and <3%, respectively. Neonatal PCR positivity rates ranged between 1.6% and 10%. After accounting for quality of studies, ranges of our primary outcomes remained almost unchanged, while among our secondary outcomes, maternal ICU admission (3–10%) and mechanical ventilation rates (1.4–5.5%) were found to be relatively lower; (4) Conclusions: Increased rates of cesarean sections and preterm birth rates were found, with iatrogenic reasons potentially involved. In cases of symptomatic women with confirmed infection, high maternal and neonatal ICU admission rates should raise some concerns. The probability of vertical transmission cannot be excluded. Further original studies on women from all trimesters are warranted.

10 January 2024 in Journal of Clinical Medicine
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DKDimitra Katsani
Dimitra Katsani
NPNefeli Paraschou
Nefeli Paraschou
EPEleni Panagouli
Eleni Panagouli
ETErmioni Tsarna
Ermioni Tsarna
TSTheodoros N. Sergentanis
Theodoros N. Sergentanis
ATArtemis Tsitsika
Artemis Tsitsika
Introduction: Egg freezing for social reasons is a process in which women who want to preserve their ability to fertilize their own oocytes at an older age freeze their eggs. With the help of in vitro fertilization, the cryopreservation of oocytes for future use is achieved. The aim of this article is to study the reasons, the risks and the effectiveness of the method from a worldwide aspect. Methods: A literature search was conducted to evaluate pertinent studies, using data from the search engines PubMed, Google and UptoDate as well as the medical literature. Results: The reasons for delayed procreation are non-medical, with the lack of an appropriate partner for a family being first on the list. The success rate of this method differs with the age of the woman, the number of fertilized eggs and other factors. Like every medical procedure, this method carries risks that relate to the mother (being of advanced age), the embryo and the procedure of in vitro fertilization. The policies that apply in each country differ depending on respective social, economic, religious and cultural factors. Due to the high cost of the method, its selection remains a choice for only a few, reinforcing social inequality. The question of the medicalization of reproduction remains unanswered in the industry of assisted reproduction. Conclusions: In conclusion, egg freezing for social reasons is gradually becoming more widely known, with the United States of America and Israel being at the top the list. Unfortunately, there is no official data registry, and consequently, no statistical results are yet available for Greece, even though it is a method that more and more women are considering. Nevertheless, there is an imperative need for a universal legal framework for all countries with respect for the needs of every woman and different social conditions. More research and data from the literature are needed in relation to the effectiveness of the method from moral and social perspectives.

21 April 2021 in Diagnostics
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Charalampos SiristatidisCharalampos Siristatidis
Charalampos Siristatidis
SSSofoklis Stavros
Sofoklis Stavros
ADAndrew Drakeley
Andrew Drakeley
SBStefano Bettocchi
Stefano Bettocchi
APAbraham Pouliakis
Abraham Pouliakis
NVNikolaos F. Vlahos
Nikolaos F. Vlahos
The prediction of in vitro fertilization (IVF) outcome is an imperative achievement in assisted reproduction, substantially aiding infertile couples, health systems and communities. To date, the assessment of infertile couples depends on medical/reproductive history, biochemical indications and investigations of the reproductive tract, along with data obtained from previous IVF cycles, if any. Our project aims to develop a novel tool, integrating omics and artificial intelligence, to propose optimal treatment options and enhance treatment success rates. For this purpose, we will proceed with the following: (1) recording subfertile couples’ lifestyle and demographic parameters and previous IVF cycle characteristics; (2) measurement and evaluation of metabolomics, transcriptomics and biomarkers, and deep machine learning assessment of the oocyte, sperm and embryo; (3) creation of artificial neural network models to increase objectivity and accuracy in comparison to traditional techniques for the improvement of the success rates of IVF cycles following an IVF failure. Therefore, “omics” data are a valuable parameter for embryo selection optimization and promoting personalized IVF treatment. “Omics” combined with predictive models will substantially promote health management individualization; contribute to the successful treatment of infertile couples, particularly those with unexplained infertility or repeated implantation failures; and reduce multiple gestation rates.

19 August 2022 in Children
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AAAngeliki Arapaki
Angeliki Arapaki
Panagiotis ChristopoulosPanagiotis Christopoulos
Panagiotis Christopoulos
Emmanouil KalampokasEmmanouil Kalampokas
Emmanouil Kalampokas
OTOlga Triantafyllidou
Olga Triantafyllidou
Alkis MatsasAlkis Matsas
Alkis Matsas
NVNikolaos F. Vlahos
Nikolaos F. Vlahos
Cancer during childhood and adolescence remains a major public health issue, affecting a significant portion of this age group. Although newer anti-cancer treatments have improved survival rates, this comes at a cost in terms of gonadotoxic effects. As a result, the preservation of fertility is important. Ovarian tissue cryopreservation, one of the newest methods, has some advantages, especially for prepubertal patients: no need for ovarian stimulation, thus, no further risk for estrogen-sensitive cancer types, and preservation of more and better-quality primordial follicles of the ovarian cortex. The most frequent indications include treatment with alkylating agents, ovarian-focused radiotherapy, leukemias, lymphomas, brain and neurological tumors, as well as Turner syndrome and benign hemoglobinopathies. An expected survival exceeding 5 years, the absence of systematic disease and an overall risk of premature ovarian insufficiency over 50% are among the criteria that need to be fulfilled in order for a patient to undertake this method. Orthotopic transplantation is more frequently used, since it can allow both live birth and the recovery of endocrine function. Reimplantation of malignant cells is always a major risk and should always be taken into consideration. Histological analysis, as well as immunohistochemical and molecular methods, are needed in order to improve the search for malignant cells before transplantation. Ovarian tissue cryopreservation appears to be a method with specific benefits, indications and risks which can be an important tool in terms of preserving fertility in younger women.

14 December 2023 in Journal of Clinical Medicine
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Alkis MatsasAlkis Matsas
Alkis Matsas
PPPanagiota Panopoulou
Panagiota Panopoulou
NANeofyta Antoniou
Neofyta Antoniou
ABAlexandra Bargiota
Alexandra Bargiota
AGAlexandros Gryparis
Alexandros Gryparis
GVGEORGIOS VALSAMAKIS
GEORGIOS VALSAMAKIS
Background and objectives: Chronic activation of the stress system has cumulative effects on the body, and it places individuals at risk for adverse health outcomes. Chronic stress has been assessed by health questionnaires in pregnancy. During the perinatal period, mothers experience increased physical and emotional demands. Chronic stress interferes with hormonal functions in mothers and infants. This meta-analysis studies the effect of maternal chronic stress during pregnancy, as assessed by established stress questionnaires, on the birth weight of their full-term infants. Design and methods: According to our criteria and after research collection, we obtained 107 studies and we conducted two types of analyses: a logistic (N = 22,342) and linear regression analysis (N = 7431). Results: Our results show that chronic stress is associated with a statistically significant risk of low birth weight (OR = 1.50, CI 95% = [1.13; 1.99], p ≤ 0.02).Conclusions: Increased maternal chronic stress, as assessed by questionnaires, in pregnancy is associated with a low-birth-weight baby. The above meta-analysis indicates that maternal high chronic stress questionnaire scores could be used as a clinical tool in order to assess low-birth-weight risk.

15 April 2021 in Healthcare
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APARGYRO POUNTOUKIDOU
ARGYRO POUNTOUKIDOU
MKMaria Potamiti Komi
Maria Potamiti Komi
VSVrisiis Sarri
Vrisiis Sarri
MPMichail Papapanou
Michail Papapanou
EREleni Routsi
Eleni Routsi
Charalampos SiristatidisCharalampos Siristatidis
Charalampos Siristatidis
Constant accumulation of data results in continuous updates of guidelines and recommendations on the proper management of pregnant women with COVID-19. This study aims to summarize the up-to-date information about the prevention and management of suspected/confirmed SARS-CoV-2 infection in obstetric patients and obstetric care during prenatal, intrapartum, and postpartum periods. We conducted a comprehensive literature search in PubMed for relevant English-written full-text reviews. We also included relevant guidelines and recommendations. In women with a low risk for infection and uncomplicated pregnancy, elective and non-urgent appointments should be postponed or completed through telehealth. Vaccination should be discussed and distance and personal hygiene preventive measures should be recommended. Routine ultrasound examinations should be adjusted in order to minimize exposure to the virus. Standardized criteria should evaluate the need for admission. Women with moderate/high-risk for infection should be isolated and tested with RT-PCR. The mode and timing of delivery should follow routine obstetric indications. In case of infection, glucocorticoids are recommended in critically ill pregnant women, after individualized evaluation. During labor and concomitant infection, the duration of the first two stages should be reduced as possible to decrease aerosolization, while minimization of hemorrhage is essential during the third stage. Close maternal monitoring and adequate oxygenation when necessary always remain a prerequisite. Discharge should be considered on the first or second day postpartum, also depending on delivery mode. Breastfeeding with protective equipment is recommended, as its benefits outweigh the risks of neonatal infection. Recommendations are currently based on limited available data. More original studies on infected pregnant women are needed to establish totally evidence-based protocols of care for these patients.