Effect of advanced paternal age on reproductive outcomes in IVF cycles of non-male-factor infertility: a retrospective cohort study / 亚洲男科学杂志(英文版)

Advanced paternal age has been overlooked, and its effect on fertility remains controversial. Previous studies have focused mainly on intracytoplasmic sperm injection (ICSI) cycles in men with oligozoospermia. However, few studies have reported on men with semen parameters within reference ranges. Therefore, we conducted a retrospective cohort study analyzing the reproductive outcomes of couples with non-male-factor infertility undergoing in vitro fertilization (IVF) cycles. In total, 381 cycles included were subgrouped according to paternal age (<35-year-old, 35-39-year-old, or ≥40-year-old), and maternal age was limited to under 35 years. Data on embryo quality and clinical outcomes were analyzed. The results showed that fertilization and high-quality embryo rates were not significantly different (all P > 0.05). The pregnancy rate was not significantly different in the 35-39-year-old group (42.0%; P > 0.05), but was significantly lower in the ≥40-year-old group (26.1%; P < 0.05) than that in the <35-year-old group (40.3%). Similarly, the implantation rate significantly decreased in the ≥40-year-old group (18.8%) compared with that in the <35-year-old group (31.1%) and 35-39-year-old group (30.0%) (both P < 0.05). The live birth rate (30.6%, 21.7%, and 19.6%) was not significantly different across the paternal age subgroups (<35-year-old, 35-39-year-old, and ≥40-year-old, respectively; all P > 0.05), but showed a declining trend. The miscarriage rate significantly increased in the 35-39-year-old group (44.8%) compared with that in the <35-year-old group (21.0%; P < 0.05). No abnormality in newborn birth weight was found. The results indicated that paternal age over 40 years is a key risk factor that influences the assisted reproductive technology success rate even with good semen parameters, although it has no impact on embryo development.

Increasing the chances of natural conception: opinion statement from the the brazilian federation of gynecology and obstetrics associations - FEBRASGO committee of gynecological endocrinology / Aumentando as chances de concepção natural: parecer da comissão nacional de ginecologia endócrina da Federação Brasileira das Associações de Ginecologia e Obstetrícia

Abstract Considering that myths and misconceptions regarding natural procreation spread rapidly in the era of easy access to information and to social networks, adequate counseling about natural fertility and spontaneous conception should be encouraged in any kind of health assistance. Despite the fact that there is no strong-powered evidence about any of the aspects related to natural fertility, literature on how to increase the chances of a spontaneous pregnancy is available. In the present article, the Brazilian Federation of Gynecology and Obstetrics Associations (FEBRASGO, in the Portuguese acronym) Committee on Endocrine Gynecology provides suggestions to optimize counseling for non-infertile people attempting spontaneous conception.

Resumo Uma vez que mitos e equívocos sobre a procriação natural se espalham rapidamente na era do fácil acesso à informação e às redes sociais, o aconselhamento adequado sobre a fertilidade natural e a concepção espontânea deve ser encorajado em qualquer tipo de assistência à saúde. Apesar do fato de não haver evidências fortes sobre qualquer dos aspectos relacionados à fertilidade natural, existe literatura sobre como aumentar as chances de uma gravidez espontânea. No presente artigo, a Comissão Nacional de Ginecologia Endócrina da Federação Brasileira das Associações de Ginecologia e Obstetrícia (FEBRASGO) oferece sugestões para otimizar o aconselhamento a pessoas que tentam a concepção espontânea, na ausência do diagnóstico de infertilidade.

Effects of paternal age on human embryo development in in vitro fertilization with preimplantation genetic screening / 대한생식의학회지

OBJECTIVE: As paternal age increases, the quality of sperm decreases due to increased DNA fragmentation and aneuploidy. Higher levels of structural chromosomal aberrations in the gametes ultimately decrease both the morphologic quality of embryos and the pregnancy rate. In this study, we investigated whether paternal age affected the euploidy rate. METHODS: This study was performed using the medical records of patients who underwent in vitro fertilization (IVF) procedures with preimplantation genetic screening (PGS) from January 2016 to August 2017 at a single center. Based on their morphological grade, embryos were categorized as good- or poor-quality blastocysts. The effects of paternal age were elucidated by adjusting for maternal age. RESULTS: Among the 571 total blastocysts, 219 euploid blastocysts were analyzed by PGS (38.4%). When the study population was divided into four groups according to both maternal and paternal age, significant differences were only noted between groups that differed by maternal age (group 1 vs. 3, p=0.031; group 2 vs. 4, p=0.027). Further analysis revealed no significant differences in the euploidy rate among the groups according to the morphological grade of the embryos. CONCLUSION: Paternal age did not have a significant impact on euploidy rates when PGS was performed. An additional study with a larger sample size is needed to clarify the effects of advanced paternal age on IVF outcomes.

Advanced paternal age how does it affect fertility and pregnancy related outcomes?

When compared to maternal age, paternal age has not attracted the same attention throughout history. Advanced paternal age has been sometimes incriminated as a possible factor that can affect pregnancy and its outcomes. In this review, we discuss the effect of paternal age on fertility, miscarriage, chromosomal abnormalities, congenital anomalies, perinatal outcomes, and neurodevelopmental disorders. In fact, advanced paternal age is associated with decreased semen quality leading to lower pregnancy rates, longer time to conception, and a higher number of miscarriages. Additionally, an increase in the rate of adverse pregnancy outcomes, such as congenital anomalies and preeclampsia, is reported when the father's age is advanced. However, no significant effect on the outcome of assisted reproductive technology [ART] or the risk of trisomies, is confirmed

Multilevel Analysis of Factors associated with Subjective Weight Perception among Normal Body Weight Adolescents based on the 2017 Korean Youth's Risk Behavior Survey (KYRBS)

PURPOSE: The present study is focused on understanding weight perception related with individual- and school-level multifactorial origins, underestimated and overestimated respectively, in normal body weight adolescents. METHODS: Using the 2017 Korea Youth Risk Behavior Web-based Survey data of 45,902 students from 799 secondary schools, a multilevel multinomial logistic regression analysis was performed where adolescents (level1) were nested within schools (level 2). RESULTS: At the school level, the average school body mass index (BMI, kg/m²) and physical education were associated with weight perception among both boys and girls. In boys, geographic areas were associated with weight underestimation. At the individual level, perceived economic status, weekly allowance, BMI (kg/m²), smartphone usage time (hrs/day) and perceived stress were associated with weight perception among both boys and girls. Age, paternal education, academic achievement and alcohol use were associated with weight perception among girls, while part-time job and physical activity were associated with weight perception among boys. CONCLUSION: Our findings underscore the importance of individual- and school-level environments in developing correct weight perception and have implications for school health education to establish healthy lifestyle behaviors for all adolescents.

The Relationship between Maternal Age at Birth and Intertwin Birth Weight Discordance in Korea

PURPOSE: To compare the relationship between intertwin birth weight discordance and maternal age at birth. METHODS: There were 51,726 pairs of twins born from 2007 to 2014 according to the birth certificate data of Korea Statistics (3,701,806 births). The data were excluded due to extra marital births, home births, and teenage births. Birth weight discordance rate (%) was calculated according to the following formula: (larger birth weight - smaller birth weight)/(birth weight of the larger twin) ×100. The odds ratio of intertwin birth weight discordance rate (≥25%) in maternal age at birth was calculated by logistic regression adjusted by the year of birth, gestational age, maternal education, infantile gender and paternal age. RESULTS: The mean birth weight of the heavier twin and that of the lighter twin were 2.536 kg and 2.254 kg, respectively. The mean birth weight difference of intertwins was 0.282 kg. The mean birth weight discordance rate by maternal age was 10.5 percent for maternal ages between 20 and 29 years, 11.0 percent for between 30 and 34 years, and 11.4 percent for 35 years and older. The frequency of birth weight discordance level of ≥25 percent increased as the maternal age increased. The rate of birth weight discordance (≥25%) was 7.7 percent for maternal ages between 20 and 29 years, 8.3 percent for between 30 and 34 years, and 8.7 percent in for 35 years and older. Compared with women from 20 to 29 years of age, the odds ratio of ≥25 percent discordance was 1.094 (95% confidence interval: 1.005~1.190) for 30 to 34 years, and 1.164 (1.401~1.301) for 35 years and older. The odds ratio of ≥25 percent discordance for the different-sexed twins was higher than that of the same-sexed twins in overall maternal age groups of 20 to 29 years, 30 to 34 years, and 35 years and older. CONCLUSION: The risk of birth weight discordance level of ≥25 percent was associated with the older maternal age. More research is required to understand the risk factors of intertwin birth weight discordance for older women.

Length of First Birth Interval and Incidence of Twin Birth in Korea; 2010~2015

PURPOSE: To compare the incidence of twin births with the length of first birth interval (LFBI: from marriage to first birth) among primiparous women. METHODS: The birth certificated data of Korea Statistics from 2010 to 2015 were used for this analysis. There were 1,356,204 births of primiparous women from total birth cases (2,736,296 births). The data involving multiparous women, teenage birth, extra-marital birth, and triplet birth cases were excluded from all analyses. Odds ratio and 95 percent confidence intervals were calculated from logistic regression to examine the risk of twin birth by LFBI adjusted for year of birth, maternal age, paternal age, age difference between couples, and maternal education and occupation. RESULTS: The frequency of LFBI was 41.5 percent in ≤12 months, 30.7 percent in 13~24 months, 13.1 percent in 25~36 months, and 2.1 percent in LFBI of ≥85 months. The mean LFBI was 21.5 months. The incidence of twin birth increased with prolonged LFBI. The twin birth rates per LFBI were 0.8 percent, 3.1 percent, 7.9 percent, and 11.0 percent in LFBI of ≤12 months, 25~36 months, 49~60 months, and 73~84 months, respectively. Odds ratio of twin births rate by LFBI were 1.510 (95% confidence interval: 1.449~1.574) for the LFBI of 13~24 months, 9.839 (9.390~10.309) for 49~60 months, and 13.244 (12.458~14.080) for ≥73~84 months, each compared with LFBI of ≤12 months. Odds ratio of twin birth rate in LFBI of ≤72 months was higher in women aged 35 and older, as compared to women aged ≤34 years. Odds ratio of twin birth rate by maternal age (≤34 years versus ≥35 years) reversed in LFBI of ≥73 months. CONCLUSION: The risk of twin birth increased significantly with prolonged LFBI. There is a need to understand the factors (fertility therapy and etc.) to increased risk of twin birth in prolonged LFBI.

Parental age is related to the occurrence of cleft lip and palate in Brazilian populations

Aim: To evaluate the association of environmental risk factors, particularly paternal and maternal age, with gender and type of oral cleft in newborn with nonsyndromic cleft lip with or without cleft palate (NSCL/P). Methods: This study included 1,346 children with NSCL/P of two Brazilian Services for treatment of craniofacial deformities. Parental ages were classified into the following groups: maternal age <35, 36-39, and ≥40 years; paternal age <39 and ≥40 years. The data was analyzed with chi-square test and multinomial logistic regression analysis. The odds ratios were estimated with a 95% confidence interval. Results: Of the 1,346 children included in this study, CLP was the type of NSCL/P with highest prevalence, followed by, respectively, CL and CP. There was a greater occurrence of NSCL/P in males compared to females (55.8% versus 44.2%). CLP was more common in men, while the CL and CP were more prevalent in women (p=0.000). No association between maternal age and clefts was observed (p=0.747). However, there was evidence of association between father's aged ≥40 years old and NSCL/P (p=0.031). When patients with CP were analyzed separately, no association between the father's age and the child's gender (p=0.728) was observed, i.e. the female gender prevails among patients with CP, regardless of the father's age. Conclusions: This study showed that there were differences in the distribution of the non-syndromic cleft lip and/or palate and the gender, and fathers aged ≥40 years old may have increased risk of oral cleft. Further studies involving different populations are needed for a better understanding of the effect of maternal and paternal ages as a risk factor for the occurrence of oral clefts (Au)

Factores de riesgo de ocurrencia y gravedad de malformaciones congénitas / Identification of risk factors for congenital malformations

Background: The relative importance of congenital malformations as a cause of death in the first year of life is increasing along with the control of preventable causes of perinatal mortality. Aim: To identify risk factors for congenital malformations. Patients and Methods: Retrospective case-control study of births registered in the database of The Latin American Collaborative Study of Congenital Malformations (ECLAMC), in the period 2001-2010. Results: Birth weight and gestational age were significantly lower in cases than controls, behaving as risk factors and associated with a greater severity of congenital malformations. The risk and severity of congenital malformations increased along with mother’s age. Fetal growth retardation, a history of congenital malformations in the family, physical factors and acute illnesses of the mother in the first trimester of pregnancy were also significant risk factors for congenital malformations and their severity. The educational level of the mother was a protective factor for congenital malformations and their severity. Conclusions: Variables previously identified as risk factors for congenital malformations, were significantly related with the occurrence of congenital malformations and their severity.

Association of ADHD symptoms severity with higher paternal and lower maternal age of a clinical sample of children

This study examines the association of father's and mother's age with the severity of inattention and hyperactivity/impulsivity. Participants are 470 children with attention deficit hyperactivity disorder [ADHD] diagnosed according to DSM-IV diagnostic criteria. Moreover, parents reported the severity of ADHD symptoms through completing ADHD checklist. Mother's and father's age was associated with the score of hyperactivity/impulsivity. Lower father's age and advanced maternal age are associated with higher severity of hyperactivity/impulsivity in children and adolescents with ADHD. None of mothers' and fathers' age is associated with ADHD inattentiveness severity in children. Maternal and paternal education levels are not associated with ADHD severity. Older mothers and younger fathers have ADHD children with higher hyperactivity/impulsivity severity. It should be investigated whether the father's and mother's age are risk factors for ADHD

[Effects of mouse paternal age on sperm parameters, reactive oxygen species levels, intraspermic antioxidants and in vitro fertilization results]

Oxidative stress as a consequence of aging can induce infertility in males. In this study, we have investigated the effects of aging on sperm parameters, intra-spermatic water soluble antioxidants, reactive oxygen species [ROS], and in vitro blastocyst formation. We chose 5 older NMRI male mice [10-12 months] and 5 younger NMRI male mice [2-3 months]. Sperm parameters, ROS, soluble antioxidants level and in vitro fertilization rate were assessed in both groups. The results were analyzed by the independent sample and chi square tests. A correlation test was performed between ROS generation and soluble antioxidant levels. Our data showed a significant decrease [P

Paternal factors in spontaneous first trimester miscarriage

To determine whether paternal factors i.e., age, tobacco use and genital tract infection increase the risk for spontaneous first trimester miscarriage. This case control study was conducted in the Department of Obstetrics and Gynaecology, Unit V / IV, Dow Medical College and Lyari General Hospital, Dow University of Health Sciences, Karachi, Pakistan. Duration of study was two and half years, from Nov, 2007 to Apr, 2010. Inclusion criteria were pregnant women with age 20 - 35 years irrespective of parity. Exclusion criteria were known medical illness in either partner, induced abortion and recurrent miscarriages. Studied paternal factors were age, tobacco use and genital tract infection. Data was computed using SPSS version 16. Significance of paternal factors was determined by Logistic Regression Analysis. Total cases studied were 200, while there were 400 controls. Mean maternal age was 27.6 +/- 4.9 years in cases and 26.5 +/- 4.5 years in controls. Mean paternal age was 35.5 +/- 6.2 years in cases and 32.3 +/- 5.4 years in controls. Paternal age was > 35 years in 54.5% cases and 16.8% controls. Spearman Bivariate correlation revealed paternal age > 35 years [p=0.000] and genital tract infection [p=0.043] as significant factors. Only paternal age >35 years [p=0.000] remained significant in Final Model after entering into logistic regression. Paternal age beyond 35 years was found to be significantly related to first trimester spontaneous miscarriages

Factors Influencing on Perinatal Outcomes of Asian Marriage Immigrant Women: Ten-year Experience in a Single Center / 대한주산의학회잡지

PURPOSE: We aimed to analyze the maternal and perinatal factors associated with perinatal outcomes by examining families comprised of Korean fathers, Asian immigrant mothers, and their newborns. METHODS: Medical records of newborn infants admitted to Jeonju Jesus Hospital nursery or ne-onatal intensive care unit (NICU) from January 2004 to June 2013 and their Asian immigrant mothers were reviewed retrospectively. The newborns were divided into two groups depending on whether they were admitted NICU or not, and factors influencing on perinatal outcomes were compared between the two groups. The newborn were divided into the two groups, including those who did not receive inpatient care and those treated in the NICU. The differences between the two groups were analyzed. RESULTS: The study included 180 newborns and 172 mothers, and 94 (52.3%) and 86 (47.7%) newborns were classified as the nursery group and the NICU group, respectively. There were no statistically significant differences between the two groups in terms of the mothers' nationality, maternal age, maternal education level, maternal occupation, residential area, maternal height and weight, maternal weight gain during pregnancy, maternal hepatitis B antigen positivity, maternal parity, paternal age, and age gap between spouses. However, underweight maternal prepregnancy body mass index (BMI) and hemoglobin level over 11.0 g/dL were significantly more frequent in the NICU group in the comparative analysis. The NICU group showed significantly more frequent no iron supplements during pregnancy (OR=4.06) and gestational disease (OR=3.81). CONCLUSION: In cases where married immigrant mothers had underweight prepregnancy BMI, gestational disease, or no iron supplements during pregnancy, their newborns were more likely to have NICU care. Therefore, married immigrant women should have appropriate perinatal care including education about a balanced diet to maintain an appropriate body weight with ensuring an adequate iron supplements intake.

Changes in Birth Rate, Perinatal Risk Factors and Outcome in Newborns in Multi-cultural Family: Ten-year Experience in One Center

PURPOSE: The aim of this study is to investigate the periodical changes of birth rate, perinatal risk factors and outcome of newborns in multi-cultural families with Korean male and non-Korean, Asian female in Gwangju, Chonnnam province. METHODS: We enrolled newborns born in or transferred from other hospital to Chonnam National University Hospital between January 2001 and December 2010. They were categorized into two periods: data from 2001 to 2005 was defined as period I and from 2006 to 2010 was defined as period II. The clinical data of the birth rate, perinatal risk factors and outcome were retrospectively reviewed. RESULTS: Number and rate of newborns in multicultural families increased significantly. The nationality of the mother changed: Vietnamese, Chinese and Cambodian significantly increased; and Japanese and Filipino significantly decreased. As the maternal age tended to be younger in period II, the age gap between the spouses increased, and the paternal age significantly increased, especially in age group of over 45 year-old. Among other perinatal risk factors, premature rupture of membranes and oligohydramnios were decreased. There were no statistical difference in morbidity (except hyperbilirubinemia) and mortality. However, congenital anomalies significantly increased. CONCLUSION: As the number of newborns in multicultural families has increased, the incidence of congenital anomalies also increased. We carefully presumed this result could be caused by increasing paternal age. Careful concern and management are needed for these families and further prospective studies are needed in a larger number of subjects.

Influence of male age on the outcome of conventional IVF-ET / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the influence of male age on the outcome of conventional IVF-ET.</p><p><b>METHODS</b>Based on male age, 170 couples undergoing conventional IVF-ET were divided into three groups: <35 yr (n = 60), 35 -39 yr (n = 77) and > or = 40 yr (n = 33). We observed the rates of fertilization, cleavage, good quality embryo, implantation, clinical pregnancy and abortion in different groups.</p><p><b>RESULTS</b>There were no significant differences among the three groups in semen volume ([3.10 +/- 1.22] ml vs [2.84 +/- 1.05] ml vs [2.80 +/- 0.79] ml), sperm concentration ([54.23 +/- 26.07] x 10(6)/ml vs [60.27 +/- 24.80] x 10(6)/ml vs [60.21 +/- 27.42] x 10(6)/ml) and sperm viability ([53.93 +/- 13.25]% vs [56.10 +/- 16.58]% vs [51.82 +/- 15.45]%) (P>0.05). The men of the > or = 40 yr group showed a significantly lower percentage of grade a + b sperm ([40.97 +/- 11.91]%) than those of the <35 and 35 - 39 yr groups ([48.47 +/- 11.78]% and [46.84 +/- 13.51]%) (P<0.05), and morphologically normal sperm ([11.76 +/- 5.97]%) than those of the <35 yr group ([15.25 +/- 6.94]% (P<0.05). The rates of fertilization, cleavage, good quality embryo, implantation, clinical pregnancy were 81.52%, 82.61%, 52.33%, 18.06% and 33.33% in the > or = 40 yr group, with no significant differences from those of the <35 yr group (83.18%, 82.68%, 56.99%, 22.40% and 40.00%) and the 35 - 39 yr group (78.78%, 80.66%, 55.01%, 21.74% and 38.96%) (P>0.05), while the abortion rate was markedly increased in the > or = 40 yr group as compared with the <35 yr group (36.36% vs 8.33%, P>0.05).</p><p><b>CONCLUSION</b>Increasing male age is related with decreasing percentages of progressively motile sperm and morphologically normal sperm, but not obviously with the rates of fertilization, good quality embryo, implantation, pregnancy and abortion.</p>

Recuperação pôndero-estatural em crianças com síndrome de Down e cardiopatia congênita / Catch up in children with Down syndrome and congenital heart disease

OBJETIVO: Avaliar o impacto das cardiopatias congênitas em crianças no crescimento de crianças com síndrome de Down (SD) e a sua recuperação pôndero-estatural após correção cirúrgica. MÉTODOS: Estudo retrospectivo de portadores da SD, entre 1984 e 2007. Excluídos os mosaicos e/ou portadores de morbidades associadas (n=165). Calcularam-se os escores Z para peso (Zpn) e comprimento (Zen) no momento do nascimento. Nos pacientes submetidos à correção cirúrgica (n=60), os escores Zp e Ze foram calculados antes da intervenção cirúrgica e em períodos posteriores, em até cinco anos de pós-operatório (PO). Em relação à população geral, Zp e Ze < 2,5 foram significativos para déficit de crescimento. Utilizado teste do Qui-Quadrado para verificar relação entre peso/estatura e idade no momento da cirurgia e teste T de Student para avaliar o momento em que ocorreu a recuperação PO (P < 0,05). RESULTADOS: As médias de Zpn (n=162) e Zen (n=156) foram -0,95 ± 1,27 e -1,348 ± 1,02. Da amostra total (n=165), 65,5% (n=108) dos pacientes apresentavam doença cardíaca. Dentre os pacientes submetidos (n=60) à cirurgia cardíaca, Zp era inferior a -2,5 em 55% (n=33) e Ze, em 60% (n=36). Com seis meses de PO, 67,4% alcançaram Zp > 2,5. Em um ano, 85,7% atingiram Ze > 2,5. Dividindo este grupo por idade, na época da cirurgia, em tercis não ocorreu diferença. CONCLUSÕES: Observou-se déficit pôndero-estatural em relação à população geral desde o nascimento, sendo maior nas crianças com cardiopatia de indicação cirúrgica. A recuperação PO ocorreu em seis meses para o peso e em um ano para a estatura, sem diferença quanto à idade no momento cirúrgico.

OBJECTIVE: To evaluate the impact of congenital heart diseases in growth of children with Down syndrome (DS) and the weight-height recovery after surgical correction. METHODS: Retrospective study of the DS patients between 1984 and 2007. Excluding the mosaics and/or patients with associated morbidities (n=165). Calculated Z scores for weight (Zwb) and length (Zlb) at birth. Those patients submitted to surgical correction (n= 60) these scores (Zw/Zh) were evaluated before surgery and in subsequent periods to five years. Malnutrition was defined as weight/height Z-score < 2.5. Used Chi-square test to verify the relation between weight/length and age at the time of surgery and Student T test to evaluate the postoperative (PO) time of recovery (P < 0.05). RESULTS: Means Zwb (n = 162) and Zlb (n = 156) were -0.95 ± 1.27 and -1.348 ± 1.02. From the total data (n = 165), 65.5% (n = 108) presented heart disease. Those submitted to cardiac surgery (n = 60), Zw was below -2.5 in 55% (n = 33) and Zh in 60% (n = 36). After six months PO, 67.4% achieved Zw > 2.5. In one year, 85.7% achieved Zh > 2.5. Dividing this group by age in tertiles at time of surgery no difference was found. CONCLUSIONS: We concluded that malnutrition common in children with DS since birth. DS children with congenital heart and surgical indication were smaller and lighter than those without or with mild disease. PO recovery occurred in 6 months for weight and one year for height, with no difference in the age at the time of surgery.

Novel concepts in male infertility

Extraordinary advances have been achieved in the field of male infertility in the last decades. There are new concepts in sperm physiology and several modern tools for the assessment of spermatogenesis kinetics in vivo. New tests using molecular biology and DNA damage assays allow the clinician to correctly diagnose men so far classified as having idiopathic male infertility. In the field of treatment, microsurgery has increased success rates either for reconstruction of the reproductive tract or the retrieval of spermatozoa for assisted conception. Emerging evidence suggests that life-style and environmental conditions are of utmost importance in male fertility and subfertility. This review discusses several concepts that have changed over the last years, such as the duration of the spermatogenic cycle in humans, Y-chromosome infertility, the reproductive potential of non-mosaic Klinefelter syndrome men, the impact of paternal age and sperm DNA in male infertility, the role of antioxidants in the treatment of infertile men, the predictive factors and techniques for sperm retrieval in non-obstructive azoospermia, and the microsurgical treatment of clinical varicoceles. Whenever possible, levels of evidence are provided as suggested by the Oxford Center of Evidence-based Medicine.

The association between paternal age and schizophrenia in a Chinese Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether advanced paternal age is related to an increased risk of schizophrenia in Chinese Han population.</p><p><b>METHODS</b>A case-control design study was performed. Three hundred and fifty-one patients with schizophrenia and 199 unrelated healthy volunteers were recruited. By using Logistic regression, paternal age was divided into five categories, and maternal age into four categories. Setting the paternal age of 26-30 years as reference, the OR, P values and 95% CI of the other paternal age categories were analyzed, respectively. The participant's sex, age and parental age at birth were used as covariants for adjusting confounding effects.</p><p><b>RESULTS</b>The OR for schizophrenia in offspring whose paternal age at birth of 31-35 years, 36-40 years, and ≥ 41 years categories were 3.834, 8.805, and 11.619 respectively. The advanced maternal age had no significant effects on the risk for schizophrenia in offspring.</p><p><b>CONCLUSION</b>The advanced paternal age was associated with elevated risk for schizophrenia in offspring among a Han Chinese population. Putative biological mechanisms may include accumulated de novo mutations and alterations in epigenetic regulations with aging in spermatogenesis.</p>

Fecundidad y fertilidad: aspectos generales / Fertility: general features

En este artículo se examina la fecundidad natural con énfasis en los factores determinantes y sus moduladores las variables diferenciales. Se presenta estrategias para el estudio de la prevalencia de la infertilidad mediante estudios basados en población o su estimación y tendencias en base a datos de nuliparidad al final de la vida reproductiva aportados por censos de población de las últimas décadas. Se revisa además, el concepto de fecundabilidad y su relación con el número de ciclos necesarios para lograr el embarazo con una probabilidad razonable de acuerdo a la edad de la mujer. Se presenta una revisión de las enfermedades de transmisión sexual más prevalentes, el tabaquismo y su asociación con la fertilidad. Finalmente, se analiza la postergación de la maternidad en el ámbito público y privado, y el efecto de la edad del hombre y la mujer sobre la fertilidad.

This study analyzes the natural fertility emphasizing the proximate determinants of fertility and differencials. The strategies to establish the prevalence of infertility through population based surveys and it trends through the study of childlessness at the end of a woman’s reproductive life are presented. Furthermore, the concept of fecundability and its association with time to conception and the woman’s age are reviewed. A revision of the most prevalent STDs and cigarette smoking and their association with fertility are presented. Finally, it is analyzed the postponement of maternity within the public and private environment and male and female age effect over fertility.