Objectives: A community dental public health program in Vancouver has been providing clinical hygiene services and oral health counseling to a limited number of high-risk, low income pregnant women for over 20 years. To enable future program decision-making, a program evaluation was undertaken with the following objectives: 1) to describe program, clients, and their oral health needs; 2) to determine whether program activities have been implemented as intended; and 3) to assess program's effectiveness in improving oral health status of clients and in improving their knowledge and behavior in relation to their own health and those of their children. Methods: The evaluation, undertaken by the resident dental hygienist, had two phases. Phase 1: Evaluability assessment, descriptive and process evaluation (retrospective and concurrent chart reviews, semi-structured interviews, appointment monitoring, and field observations). Phase 2: A short- and medium-term outcome evaluation with a convenience sample who attended over a 1-year period. Data, collected by questionnaires, interviews, clinical indices, chart review, field observations, and appointment statistics, was analyzed with a combination of univariate and bivariate analyses. Results: Phase 1: Stakeholders' goals were identified; a logic model and organizational flowchart were developed. Chart review (N=123) revealed mean client age of 27 years; 28% Canadian-born; 48% had other children; 78% were concerned about "bleeding gums"; and 63% had visible tooth decay. 28% of women referred to the program never attended. Unfamiliarity of clients with the dental "experience", language barriers, and clinic operation and time restraints affected implementation of program's activities. Phase 2: Outcomes in clients (N=61) demonstrated significant improvements (P<0.05) in clinical indices, oral health knowledge and tooth brushing skills, and dental care for clients' children. A positive program experience was reported from all the women. However, 79% (48/61) of clients never obtained the "outside" dental services that they needed. Conclusions: Evaluation revealed positive changes, extending into the postnatal period in knowledge, behaviors and clinical outcomes despite language barriers, insufficient resources, and ill-defined program goals. Identified program limitations need to be addressed to further improve outcomes of this promising intervention. Research was partially supported by a grant from the British Columbia Dental Hygienists Association. / Dentistry, Faculty of / Graduate

A comparative study of two groups of primiparas was conducted in Vancouver, British Columbia (Canada), during the summer of 1976. The first group was comprised of those women who attended 50 per cent or more of a series of prenatal classes (the attenders), and was compared to a group of non-attenders, those who had not attended prenatal classes during their pregnancy. The objective of the study was to examine those factors which are expected to influence utilization of prenatal educational programs. The long-term objective was to generate data which could be used to improve these programs; and, consequently, also to improve the health of the mother and child. From a total sample of 154 primiparas drawn from the mothers having given birth to a live baby in April, May or June 1976, 127 were interviewed: 54 non-attenders and 73 attenders. The comparison of the groups of attenders and non-attenders showed the following results: 1) There were differences between the two groups in regard to basic socio-economic and demographic characteristics. In general, the non-attenders tended to be younger, less educated, poorer, new immigrants, and less fluent in English than the attenders. 2) When tested on a set of knowledge questions, the two groups showed differences in the areas of pregnancy, childbirth and child care knowledge. In general, the attenders responded correctly to more of the questions than did the non-attenders. However, on some questions, the differences were not very large and it would be interesting to re-examine these differences when confounding factors are controlled (e.g., English fluency). The comparison of behavioural health practices revealed the following: The non-attenders were less likely to smoke during pregnancy than were the attenders. - The two groups were fairly comparable in terms of a positive change in their nutrition habits during pregnancy. - As expected, more attenders than non-attenders used controlled breathing techniques during the delivery. Seventy-six per cent of the non-attenders either partially or totally breastfed their babies compared with 55 per cent of the attenders. When asked about their reasons for not attending prenatal classes, the non-attenders most frequently mentioned a lack of awareness of the existence of the classes and a general feeling that it was unnecessary to attend. Difficulty in speaking and understanding English was also a factor in non-utilization of classes. In regard to wife-husband relationships, husbands were given as a source of support by more attenders than non-attenders, although the difference was not statistically significant. It could be worthwhile to investigate this area more thoroughly to determine whether the presence of support from a husband/partner is a reason for attendance or occurs as a result of the attendance. The data on knowledge and behavioural health practices could raise questions concerning the effectiveness of the prenatal programs. However, this study has not been designed to evaluate these programs. Most of the factors studied regarding knowledge and health practices are known to be associated with socio-economic and cultural factors. An analysis of the true effect of the program should take these factors into consideration. In conclusion, this study has shown ways of increasing utilization of prenatal educational programs. Emphasis should be placed on the following: The target population - More effort and resources should be devoted to reach lower socio-economic groups, new immigrants, and those less fluent in the English language. The method - New communication and information dissemination techniques, as well as diversified teaching methods, should be developed (e.g., more courses should be taught in a language other than English). The content - Given the differences in knowledge levels and health practices, the content should be geared more to meet the needs of specific sub-groups in the population. Publicity - The study demonstrates the need for making better known the existence of the program as well as its present objectives. This study has raised a number of questions regarding both utilization of prenatal care and outcome measures relating to this care. Therefore, a larger and well designed study to investigate these questions more extensively is recommended. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate

OBJETIVO: Determinar los conocimientos, actitudes y prácticas relacionados a la suplementación con ácido fólico en gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016. METODOLOGÍA: estudio con enfoque mixto (cuali-cuantitativo), para la fase cualitativa se realizó un estudio descriptivo y para la fase cuantitativa un estudio observacional con diseño descriptivo, de corte transversal. Para la fase cualitativa estuvo conformado por 7 gestantes y en la fase cuantitativa estuvo conformada por 169 gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016 las cuales fueron seleccionadas con un muestreo probabilístico aleatorio simple. RESULTADOS: la edad promedio de las gestantes encuestadas fue 32.07 años, estando la mayoría (62.7%) entre 20 a 34 años, el 45.6% era casada, el 74% tenía estudios superiores, el 62.7% trabajaba y el 60.4% procedía de Lima; igualmente se encontró que el 43.8% era multigesta y el 58.6% uno a dos hijos vivos. El 78.7% dijo que recibió información sobre ácido fólico antes o durante el embarazo, el 56.2% durante la atención prenatal, el 7.7% en la sesión de psicoprofilaxis obstétrica y el 2.4% en la sala de espera. El nivel de conocimiento sobre la suplementación de ácido fólico en el 81.1% fue “Medio”, el 10.7% “Bajo” y el 8.3% “Alto”. Las actitudes hacia la suplementación con ácido fólico en el 56.2% fueron “Buenas”, en el 43.2% “Regulares” y en el 0.6% una actitud “Mala”. La opinión de las gestantes respecto al consumo de ácido fólico fue que era necesario para prevenir algún problema en el bebé, ya sea en su desarrollo intrauterino, a nivel del tubo neural, o al nacimiento y que esta vitamina la encontrarían en los vegetales de hojas verdes (espinaca), las frutas, el hígado, los frutos secos y el pescado. La mayoría reconoce que el personal de salud debe de recomendar el consumo como una obligación funcional, para tener mayor conocimiento y llevar mejor el embarazo. CONCLUSIÓN: El nivel de conocimiento de las gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016 fue Medio (81.1%), las actitudes Buenas (56.2%) y en cuanto a las prácticas, solo un 44.4% consumió suplemento de ácido fólico antes del embarazo y el 100% lo consumió durante el embarazo. PALABRAS CLAVES: Conocimientos, actitudes, practicas, suplementación, ácido fólico, gestantes / --- OBJECTIVE: To determine the knowledge, attitudes and behaviors related to supplementation with folic acid in pregnant practices attending prenatal care at the National Hospital Edgardo Rebagliati Martins during the period from January to February 2016. METHODOLOGY: study mixed approach (qualitative and quantitative) for the qualitative phase, a descriptive study and the quantitative phase with descriptive observational study design, cross section. For the qualitative phase was composed of seven pregnant women and the quantitative phase consisted of 169 pregnant women attending prenatal care in the National Edgardo Rebagliati Martins Hospital during the period from January to February 2016 which were selected with a probability random sampling simple. RESULTS: the average age of pregnant women surveyed was 32.07 years, the majority (62.7%) between 20 to 34 years, 45.6% were married, 74% had higher education, 62.7% worked and 60.4% came from Lima being; also found that 43.8% were multigesta and 58.6% one to two surviving children. 78.7% said they received information about folic before or during pregnancy acid, 56.2% during prenatal care, 7.7% in the session of obstetrical psycho and 2.4% in the waiting room. The level of knowledge about folic acid supplementation 81.1% was "Medium", 10.7% "Low" and 8.3% "High". Attitudes toward supplementation with folic acid in 56.2% were "good", in 43.2% "Regular" and 0.6% "bad" attitude. The opinion of pregnant women regarding folic acid intake was that it was necessary to prevent any problems in the baby, either in its intrauterine development at the level of neural tube, or at birth and that this vitamin would find in leafy vegetables green (spinach), fruits, liver, nuts and fish. Most people recognize that health personnel should recommend consumption as a functional requirement to have greater knowledge and better carry the pregnancy. CONCLUSION: The level of knowledge of pregnant women attending prenatal care in the Edgardo Rebagliati Martins National Hospital during the period from January to February 2016 was the Middle (81.1%), good attitudes (56.2%) and as to the practices, only 44.4% consumed folic acid before pregnancy and 100% consumed during pregnancy. KEYWORDS: Knowledge, attitudes, practices, supplementation, folic acid, pregnant. / Tesis

OBJETIVO: Determinar los conocimientos, actitudes y prácticas relacionados a la suplementación con ácido fólico en gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016. METODOLOGÍA: estudio con enfoque mixto (cuali-cuantitativo), para la fase cualitativa se realizó un estudio descriptivo y para la fase cuantitativa un estudio observacional con diseño descriptivo, de corte transversal. Para la fase cualitativa estuvo conformado por 7 gestantes y en la fase cuantitativa estuvo conformada por 169 gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016 las cuales fueron seleccionadas con un muestreo probabilístico aleatorio simple. RESULTADOS: la edad promedio de las gestantes encuestadas fue 32.07 años, estando la mayoría (62.7%) entre 20 a 34 años, el 45.6% era casada, el 74% tenía estudios superiores, el 62.7% trabajaba y el 60.4% procedía de Lima; igualmente se encontró que el 43.8% era multigesta y el 58.6% uno a dos hijos vivos. El 78.7% dijo que recibió información sobre ácido fólico antes o durante el embarazo, el 56.2% durante la atención prenatal, el 7.7% en la sesión de psicoprofilaxis obstétrica y el 2.4% en la sala de espera. El nivel de conocimiento sobre la suplementación de ácido fólico en el 81.1% fue “Medio”, el 10.7% “Bajo” y el 8.3% “Alto”. Las actitudes hacia la suplementación con ácido fólico en el 56.2% fueron “Buenas”, en el 43.2% “Regulares” y en el 0.6% una actitud “Mala”. La opinión de las gestantes respecto al consumo de ácido fólico fue que era necesario para prevenir algún problema en el bebé, ya sea en su desarrollo intrauterino, a nivel del tubo neural, o al nacimiento y que esta vitamina la encontrarían en los vegetales de hojas verdes (espinaca), las frutas, el hígado, los frutos secos y el pescado. La mayoría reconoce que el personal de salud debe de recomendar el consumo como una obligación funcional, para tener mayor conocimiento y llevar mejor el embarazo. CONCLUSIÓN: El nivel de conocimiento de las gestantes que acuden a su atención prenatal en el Hospital Nacional Edgardo Rebagliati Martins durante el periodo de enero a febrero del 2016 fue Medio (81.1%), las actitudes Buenas (56.2%) y en cuanto a las prácticas, solo un 44.4% consumió suplemento de ácido fólico antes del embarazo y el 100% lo consumió durante el embarazo. PALABRAS CLAVES: Conocimientos, actitudes, practicas, suplementación, ácido fólico, gestantes / --- OBJECTIVE: To determine the knowledge, attitudes and behaviors related to supplementation with folic acid in pregnant practices attending prenatal care at the National Hospital Edgardo Rebagliati Martins during the period from January to February 2016. METHODOLOGY: study mixed approach (qualitative and quantitative) for the qualitative phase, a descriptive study and the quantitative phase with descriptive observational study design, cross section. For the qualitative phase was composed of seven pregnant women and the quantitative phase consisted of 169 pregnant women attending prenatal care in the National Edgardo Rebagliati Martins Hospital during the period from January to February 2016 which were selected with a probability random sampling simple. RESULTS: the average age of pregnant women surveyed was 32.07 years, the majority (62.7%) between 20 to 34 years, 45.6% were married, 74% had higher education, 62.7% worked and 60.4% came from Lima being; also found that 43.8% were multigesta and 58.6% one to two surviving children. 78.7% said they received information about folic before or during pregnancy acid, 56.2% during prenatal care, 7.7% in the session of obstetrical psycho and 2.4% in the waiting room. The level of knowledge about folic acid supplementation 81.1% was "Medium", 10.7% "Low" and 8.3% "High". Attitudes toward supplementation with folic acid in 56.2% were "good", in 43.2% "Regular" and 0.6% "bad" attitude. The opinion of pregnant women regarding folic acid intake was that it was necessary to prevent any problems in the baby, either in its intrauterine development at the level of neural tube, or at birth and that this vitamin would find in leafy vegetables green (spinach), fruits, liver, nuts and fish. Most people recognize that health personnel should recommend consumption as a functional requirement to have greater knowledge and better carry the pregnancy. CONCLUSION: The level of knowledge of pregnant women attending prenatal care in the Edgardo Rebagliati Martins National Hospital during the period from January to February 2016 was the Middle (81.1%), good attitudes (56.2%) and as to the practices, only 44.4% consumed folic acid before pregnancy and 100% consumed during pregnancy. KEYWORDS: Knowledge, attitudes, practices, supplementation, folic acid, pregnant. / Tesis

BACKGROUND: Preeclampsia is one of the leading causes of maternal and perinatal morbidity and mortality, affecting 2-8% of pregnancies worldwide. It is estimated that 76,000 women and 500,000 babies die from this disease each year globally. Preeclampsia is characterized as hypertension associated with the onset of proteinuria, maternal organ dysfunction or uteroplacental dysfunction occurring at or after 20 weeks of gestation. In addition to its effects on pregnancy, preeclampsia may also have long-term adverse effects on women who experience the disorder and their children later on in life. Currently, the only cure for preeclampsia is delivery, which is often associated with preterm birth, increasing the risk of neonatal death. Daily low-dose aspirin (81mg) has been shown to have a preventive effect on preeclampsia in women at high risk of developing the disorder. OBJECTIVE: To analyze patient data collected at Boston Medical Center to determine the effects of prescribed low dose prenatal aspirin (81 mg) on pregnancy outcomes. METHODS: There were 2648 obstetric deliveries at Boston Medical Center in the two-year span of 2017-2018. Using R, statistical analyses were performed to determine the difference in birth outcomes between the prenatal aspirin prescribed group and the non-aspirin prescribed group as well as the effect of prenatal aspirin on pregnancy outcomes. Logarithmic and linear models as well as basic statistical methods were employed for the analyses. RESULTS: The prenatal aspirin prescribed population had higher major and moderate risk factors as well as worse birth outcomes, Apgar scores and birthweight as compared with the non-prescribed population. However, prenatal aspirin may reduce the adverse effects of both major and moderate risk factors on birth outcomes. CONCLUSIONS: Prenatal aspirin may have beneficial effects on birth outcomes, and the pregnant population at Boston Medical Center may benefit from taking low-dose aspirin. This study was carried out retrospectively with a cohort that was not randomized, so this conclusion needs to be verified by future studies.

Fetal Movement (FM) has been studied as a prenatal manifestation of activity level, a core dimension of many temperament theories. However, there has been little research exploring the significance of variability in the pattern of FM. The current study uses hierarchical linear modeling to compute the developmental function of FM in the third trimester. This study also examined how variability in the pattern of FM, in contrast to mean FM, predicted infant development. The following hypotheses were tested: 1. Mean FM will predict infant development at 3 and 6 months; 2. The developmental function of FM will display an inverted-U shape with significant variability; and 3. The pattern of FM will predict infant outcome at 3 and 6 months. Thirty-three mothers were asked to provide weekly counts of FM. Infant temperament, mental development, and motor development were assessed at 3 and 6 months. The best-fitting pattern describing FM was a piecewise linear function with FM increasing until 34 weeks gestation and thereafter decreasing, but variability was noted. The overall mean FM and pattern of FM were differentially associated with infant development. Higher mean FM was associated with increases in negative affect and decreases in orienting/regulation across 3 to 6 months. Mean FM also predicted infant size. The pattern of FM was related to different outcome variables. Increases in FM early and decreases in FM late in the third trimester were associated with less activity and greater emotional tone and attention at 3 months. This same pattern of FM was related to weighing more at 6 months, decreasing in extraversion from 3 to 6 months, and becoming more active from 3 to 6 months of age. The results indicate that the pattern of FM provides information about subsequent development that is different from mean FM. Whereas mean FM was associated with aspects of difficult temperament, the pattern of FM predicted more positive outcomes. These findings suggest that the pattern of FM may be useful as a prenatal assessment of postnatal development.

Ette thèse est centrée sur les capacités sensorielles, cognitives et sur les effets du stress chez deux espèces de seiche : Sepia officinalis et Sepia pharaonis. Nous avons d’abord démontré que les embryons répondent à différents stimuli environnementaux (lumière, proies, prédateurs, encre de seiche) mettant en évidence que l'information sensorielle passe à travers la capsule de l'œuf, ce qui permet une continuité sensorielle transnatale. De telles réponses sont possibles puisque leur système chimiosensoriel et visuel sont fonctionnels avant l'éclosion. Nous avons également montré que les embryons des deux espèces sont capables d'apprentissage simple (empreinte alimentaire) et associatif (conditionnement classique) et que ces capacités précoces pourraient augmenter leurs chances de survie avant et après l'éclosion en permettant la reconnaissance des proies et des prédateurs. Enfin, nous avons montré que le stress embryonnaire naturel (odeur de prédateur) et artificiel (lumière) ont des effets modérés voire nuls sur les capacités d’apprentissage périnatal. Ces résultats comportementaux ont été observés sans grande différence entre les deux espèces qui vivent pourtant dans des environnements très éloignés. Pris ensemble, ces résultats démontrent que les embryons de seiche ne sont pas isolés de leur environnement mais détectent et traitent les informations environnementales qui modulent leur comportement après l’éclosion. / The focus of this thesis centres on the sensory, cognitive abilities and stress effect of two cuttlefish species: Sepia officinalis and Sepia pharaonis. First, we demonstrated that embryos respond to different environmental stimuli (i.e. light, prey, predators, ink) showing that sensory information passes through the egg capsule which allows a sensory transnatal continuity. Such responses to external stimuli are likely facilitated through their visual and chemosensory systems that are functional prior to hatching. We also demonstrated that the embryos of these two species are capable of simple learning (food imprinting) and associative learning (classical conditioning). These early abilities might increase their survival chance before and after hatching because they allow prey and predator recognition event before hatching. Finally, we showed that both natural embryonic stress (predatory odour) and artificial stress (light) have moderate or no effects on perinatal learning abilities. The same behavior was observed on the two species whereas they live in different continent. Taken together, these results demonstrate that cuttlefish embryos are not isolated from their environment, but rather detect and process external information which shapes their behaviors after hatching.

Background: Rates of preterm delivery, a major proximate cause of perinatal morbidity and mortality, have been increasing. Prenatal alcohol exposure has been implicated in preterm delivery, although results have been inconsistent due to inadequate control for confounding factors, insufficient power, unreliable and inaccurate assessment of both exposure and gestational age, and lack of stratification of prematurity into severity levels. The purpose of this study was to examine the relation between maternal alcohol, cocaine and cigarette use during pregnancy, and extreme and mild preterm birth. Methods: Three thousand one hundred thirty consecutive gravidas were followed prospectively for antenatal substance use and had ultrasound confirmed pregnancy dating. Results: Alcohol and cocaine, but not cigarette use, were associated with increased risk of extreme preterm delivery after control for potential confounders. For every unit increase in alcohol exposure, risk of extreme preterm delivery increased significantly [odds ratio (OR) 34.8]. Furthermore, in women aged 30+, alcohol exposure was associated with mild prematurity. Abstention from alcohol while continuing to use cocaine and tobacco was related to a decrease in extreme prematurity of 41%. Conclusions: The risk of extreme preterm delivery associated with alcohol use is substantial and similar in magnitude to other well-recognized risks. Increased accuracy in identifying exposure and the use of ultrasound to confirm gestational age dating likely contributed to the findings of the current study. These findings suggest that eliminating pregnancy alcohol use might substantially reduce the risk of preterm delivery.

Background: There are few studies on the uptake of non-invasive prenatal screening, but those available suggest substantial variation in uptake in the initial years in which it was offered. There is a need to update the earlier evidence and determine whether there has been any change in usage trends as the number of users have increased. This will help inform policy makers about NIPT uptake under currently existing policies and guidelines which can help inform whether to maintain or refine policies on NIPT. Objectives: The primary objective of this thesis was to investigate recent trends in NIPT utilization, and the secondary objective was to identify differences between pregnant individuals aged 40 years and above and/or with a history of previous aneuploidy who opted for first-tier (first-line screening) or second-tier (contingent screening) NIPT and pregnant individuals aged less than 40 years with no history of previous aneuploidy. Methods: This retrospective cohort study used a province wide birth registry from Ontario and the population studied comprised pregnant individuals with an expected date of delivery from August 1st, 2016 to March 31st, 2020. Results: Of 536,748 pregnant individuals resident in Ontario during the study period, 27,733 were classified as high-risk of giving birth to a baby with a chromosomal aneuploidy and 509,015 were classified as low-risk of giving birth to a baby with a chromosomal aneuploidy. Uptake of NIPT has increased every year since 2016. We found substantial variation in NIPT between regions within the province. Highest uptake was found in urban areas, highest neighbourhood of income and education quintiles, high-risk population, among those with a prenatal care visit in the first trimester, multiple pregnancy, multigravidity, body mass index within the normal range (18.5-24.9 kg/m2), and OHIP funding. Conclusion: Our results suggest a need to provide more education/training about NIPT and funding eligibility to health professionals and pregnant individuals, including low-risk pregnant individuals in the first-tier (first-line screening) NIPT funding policy, to ensure equitable assess.

Chromosome abnormalities are one of the most important causes of congenital disorders. The main goal of this research is to give a broad view of the use and evolution of prenatal and postnatal cytogenetic diagnosis in Girona province between 1999 and 2009. It also aims at linking prenatal cytogenetic diagnosis with the existing screening methods. The main conclusions are the following: - A rise in the use of cytogenetic diagnosis has been detected. This has been caused by a growing preventive medicine trend. - Case studies match the literature consulted when the study population is similar in accordance with national health policies. - The overall sensitivity of obstetric ultrasound scan was 60,8%, and this result matches, and in many cases exceeds, those found in the literature consulted. - The moving from second-trimester to first-trimester aneuploidy prenatal screening has meant a significant increase in aneuploidy detections. - Prenatal cytogenetic diagnosis appears as an interdisciplinary field in which the extent of prenatal screening tests, like obstetric ultrasound scans and aneuploidy screening, is crucial. / Les anomalies cromosòmiques són una de les causes més importants dels defectes congènits. L’objectiu d’aquest treball és donar una visió global de l’ús i l’evolució del diagnòstic citogenètic prenatal i postnatal a les comarques de Girona en el període 1999-2009 i relacionar el diagnòstic citogenètic prenatal amb els diferents mètodes de cribratge. Les conclusions principals són: - Es constata un augment de l’ús del diagnòstic citogenètic com a resultat d’una tendència creixent en medicina preventiva. - La casuística coincideix amb la bibliografia consultada quan la població d’estudi és semblant, atenent a la política sanitària del país. - La sensibilitat global de l’ecografia obstètrica va ser del 60,8%, i és un resultat concordant i en molts casos millor en comparació amb la literatura consultada. - La substitució del cribratge del segon trimestre pel cribratge del primer trimestre ha suposat un increment important en la detecció d’aneuploïdies. - El diagnòstic citogenètic prenatal es mostra com a una àrea interdisciplinària en què la contribució de les proves de cribratge prenatal com l’ecografia obstètrica i el cribratge d’aneuploïdies són importants.