In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertai...In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man＇s secondary sex ratio （F1 generation） by directly examining the sex chromosomes of his sperm. We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization （FISH）. Patient demographic and semen parameters were recorded. Chi-squared analysis was used to compare gender ratios （Y chromosomes/total chromosomes）. Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters. A total of 185 men underwent sperm FISH. For the entire cohort, the proportion of Y chromosome-bearing sperm was 51.5%. Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm （50.8%） compared to men with higher sperm counts （51.6%; P= 0.02）. After multivariable adjustment, a higher sperm concentration, total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm （P〈0.01）. As a man＇s sperm production declines, so does the proportion of Y chromosome-bearing sperm. Thus, a man＇s reproductive potential may predict his ability to sire male offspring.展开更多
Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis, Markedly, fewer studies have investigated thos...Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis, Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring＇s reproductive fitness （e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes）. Conversely, parents with poor male fertility genes would produce primarily daughters, We tested whether there was an association between how fast a man＇s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man＇s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm （judged using computer-assisted sperm analysis （CASA）） than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future eDidemiological and clinical studies of human fertility,展开更多
The aim of this study was to evaluate the association between semen quality and the secondary sex ratio （SSR）, defined as the ratio of male to female live births. Our study cohort comprised 227 male partners who wer...The aim of this study was to evaluate the association between semen quality and the secondary sex ratio （SSR）, defined as the ratio of male to female live births. Our study cohort comprised 227 male partners who were enrolled prior to conception in Michigan and Texas between 2005 and 2009, and prospectively followed through delivery of a singleton birth. The male partners provided a baseline and a follow-up semen sample a month apart. Semen analysis was conducted to assess 27 parameters including five general characteristics, six sperm head measures, 14 morphology measures, and two sperm chromatin stability assay measures. Modified Poisson regression models with a robust error variance were used to estimate the relative risk （RR） and 95% confidence interval （95% CI） of a male birth for each semen parameter, after adjusting for potential confounders. Of the 27 semen parameters, only the percentage of bicephalic sperm was significantly associated with the SSR （2nd VS Ist quartile, RR, 0.65, 95% CI, 0.45-0.95, P= 0.03; 4TM vs 1St quartile, RR, 0.61, 95% CI, 0.38-1.00, P 〈 0.05 before rounding to two decimal places）, suggestive of a higher percentage of bicephalic sperm being associated with an excess of female births. Given the exploratory design of the present study, this preconception cohort study suggests no clear signal that human semen quality is associated with offspring sex determination.展开更多
目的探讨行体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)治疗出生子代性别比(secondary sex ratio,SSR)的相关影响因素。方法收集2013年6月至2021年6月在广州中医药大学第二附属医院生殖医学科接受体外受精-...目的探讨行体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)治疗出生子代性别比(secondary sex ratio,SSR)的相关影响因素。方法收集2013年6月至2021年6月在广州中医药大学第二附属医院生殖医学科接受体外受精-胚胎移植治疗分娩的胎儿性别数据,分别按移植卵裂期胚胎与囊胚、体外受精与卵胞浆内单精子显微注射(intracytoplasmic sperm insemination,ICSI)受精胚胎、不同来源精子行ICSI治疗胚胎进行分组比较,并按多因素logistic回归分析法进行分析。计量资料采用单因素ANOVA检验(方差齐),计数资料采用χ^(2)检验及Fisher’s确切概率法。结果IVF-ET治疗男女出生性别比为116∶100(1158∶998)。移植卵裂期胚胎1310个分娩周期与移植囊胚433个分娩周期进行比较,出生男女性别比:108∶100(870/809)比147∶100(277/189),差异存在统计学意义(P<0.05)。移植IVF胚胎1306个分娩周期与移植ICSI胚胎433个分娩周期进行比较,出生男女性别比为121∶100(879/724)比97∶100(264/272),差异有统计学意义(P<0.05)。穿刺取精来源精子男女出生性别比为90.2∶100(37∶41),不同来源精子行ICSI治疗出生子代性别比差异无统计学意义(P>0.05),睾丸穿刺来源精子子代出生性别比略高于附睾穿刺来源精子子代出生性别比。logistic回归分析显示移植胚胎期别是影响出生性别比的独立危险因素。结论囊胚移植出生性别比高于卵裂期胚胎出生性别比,移植IVF受精胚胎出生性别比高于移植ICSI受精胚胎出生性别比。胚胎期别是影响出生性别比的独立危险因素。展开更多
By comparing the different developmental characteristics of two types of sperm nucleiwhich were from gynogenetic fish (crucian carp) and amphimictic fishes (red carp, redgoldfish and sex--reversal red carp) respective...By comparing the different developmental characteristics of two types of sperm nucleiwhich were from gynogenetic fish (crucian carp) and amphimictic fishes (red carp, redgoldfish and sex--reversal red carp) respectively in the eggs of gynogenetic crucian carp, itwas preliminarily revealed that there existed selective inhibiting actions of the primarycontrol in the eggs of crucian carp for inhibiting the development of the two types of spermnuclei. To homologous sperms, the primary control showed weak effect, thus leading tothe decondensation of homologous sperm nuclei at different degrees in the eggs of cruciancarp. But to heterologous sperms, the primary control showed strong effects, resulting in thetotal inhibition of the development of heterologous sperm nuclei. Moreover, our experimentalresults also showed that the different developmental behavior of the two types of spermnuclei might have a great relationship to the changes or the sex ratio in the population ofgynogenetic crucian carp. The infiltration of 'the genetic materials in sperm nuclei' intothe female nucleus at random might play an important role in male emergence in the naturallygynogenetic population of crucian carp.展开更多
目的探究辅助生殖技术中出生单胎新生儿第二性别比(secondary sex ratio,SSR)的影响因素。方法回顾性队列研究分析2000年1月至2018年12月期间在中国科学技术大学附属第一医院(安徽省立医院)生殖中心通过辅助生殖技术治疗出生的7020例单...目的探究辅助生殖技术中出生单胎新生儿第二性别比(secondary sex ratio,SSR)的影响因素。方法回顾性队列研究分析2000年1月至2018年12月期间在中国科学技术大学附属第一医院(安徽省立医院)生殖中心通过辅助生殖技术治疗出生的7020例单胎新生儿的临床资料,分析新生儿的母亲年龄、授精方式、移植胚胎类型、移植胚胎期别等因素对单胎新生儿性别的影响。结果在7020例新生儿中,男婴3730例,女婴3290例,总SSR为113∶100。体外受精(in vitro fertilization,IVF)方式出生新生儿SSR明显高于卵胞质内单精子注射(intracytoplasmic sperm injection,ICSI)授精方式(121∶100比95∶100,P<0.001),其他因素对出生新生儿SSR无显著影响。分层分析中,在IVF组和ICSI组间除了母亲年龄≥35岁组、囊胚期胚胎移植组的IVF和ICSI出生的SSR差异无统计学意义(P>0.05)外,其余各组的IVF出生新生儿的SSR都高于ICSI(<35岁组:P<0.001;新鲜胚胎组:P=0.001;冻融胚胎组:P=0.003;卵裂期胚胎移植组:P<0.001)。在IVF组内和ICSI组内分析显示各影响因素之间的SSR差异没有统计学意义(P>0.05)。单因素logistic回归分析显示,单胎妊娠中授精方式对新生儿SSR产生的影响有统计学意义(OR=0.792,95%CI=0.712~0.881,P<0.001)。去除混杂因素后logistic回归分析显示,单胎妊娠中授精方式对新生儿SSR影响有统计学意义(aOR=0.793,95%CI=0.713~0.883,P<0.001)。结论授精方式是辅助生殖技术中影响出生单胎SSR的因素,IVF较ICSI可提高SSR比值。展开更多
文摘In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man＇s secondary sex ratio （F1 generation） by directly examining the sex chromosomes of his sperm. We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization （FISH）. Patient demographic and semen parameters were recorded. Chi-squared analysis was used to compare gender ratios （Y chromosomes/total chromosomes）. Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters. A total of 185 men underwent sperm FISH. For the entire cohort, the proportion of Y chromosome-bearing sperm was 51.5%. Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm （50.8%） compared to men with higher sperm counts （51.6%; P= 0.02）. After multivariable adjustment, a higher sperm concentration, total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm （P〈0.01）. As a man＇s sperm production declines, so does the proportion of Y chromosome-bearing sperm. Thus, a man＇s reproductive potential may predict his ability to sire male offspring.
文摘Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis, Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring＇s reproductive fitness （e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes）. Conversely, parents with poor male fertility genes would produce primarily daughters, We tested whether there was an association between how fast a man＇s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man＇s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm （judged using computer-assisted sperm analysis （CASA）） than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future eDidemiological and clinical studies of human fertility,
文摘The aim of this study was to evaluate the association between semen quality and the secondary sex ratio （SSR）, defined as the ratio of male to female live births. Our study cohort comprised 227 male partners who were enrolled prior to conception in Michigan and Texas between 2005 and 2009, and prospectively followed through delivery of a singleton birth. The male partners provided a baseline and a follow-up semen sample a month apart. Semen analysis was conducted to assess 27 parameters including five general characteristics, six sperm head measures, 14 morphology measures, and two sperm chromatin stability assay measures. Modified Poisson regression models with a robust error variance were used to estimate the relative risk （RR） and 95% confidence interval （95% CI） of a male birth for each semen parameter, after adjusting for potential confounders. Of the 27 semen parameters, only the percentage of bicephalic sperm was significantly associated with the SSR （2nd VS Ist quartile, RR, 0.65, 95% CI, 0.45-0.95, P= 0.03; 4TM vs 1St quartile, RR, 0.61, 95% CI, 0.38-1.00, P 〈 0.05 before rounding to two decimal places）, suggestive of a higher percentage of bicephalic sperm being associated with an excess of female births. Given the exploratory design of the present study, this preconception cohort study suggests no clear signal that human semen quality is associated with offspring sex determination.
文摘目的探讨行体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)治疗出生子代性别比(secondary sex ratio,SSR)的相关影响因素。方法收集2013年6月至2021年6月在广州中医药大学第二附属医院生殖医学科接受体外受精-胚胎移植治疗分娩的胎儿性别数据,分别按移植卵裂期胚胎与囊胚、体外受精与卵胞浆内单精子显微注射(intracytoplasmic sperm insemination,ICSI)受精胚胎、不同来源精子行ICSI治疗胚胎进行分组比较,并按多因素logistic回归分析法进行分析。计量资料采用单因素ANOVA检验(方差齐),计数资料采用χ^(2)检验及Fisher’s确切概率法。结果IVF-ET治疗男女出生性别比为116∶100(1158∶998)。移植卵裂期胚胎1310个分娩周期与移植囊胚433个分娩周期进行比较,出生男女性别比:108∶100(870/809)比147∶100(277/189),差异存在统计学意义(P<0.05)。移植IVF胚胎1306个分娩周期与移植ICSI胚胎433个分娩周期进行比较,出生男女性别比为121∶100(879/724)比97∶100(264/272),差异有统计学意义(P<0.05)。穿刺取精来源精子男女出生性别比为90.2∶100(37∶41),不同来源精子行ICSI治疗出生子代性别比差异无统计学意义(P>0.05),睾丸穿刺来源精子子代出生性别比略高于附睾穿刺来源精子子代出生性别比。logistic回归分析显示移植胚胎期别是影响出生性别比的独立危险因素。结论囊胚移植出生性别比高于卵裂期胚胎出生性别比,移植IVF受精胚胎出生性别比高于移植ICSI受精胚胎出生性别比。胚胎期别是影响出生性别比的独立危险因素。
基金Project supported by the National Natural Science Foundation of China and the Natural Science Foundation of Hubei Province.
文摘By comparing the different developmental characteristics of two types of sperm nucleiwhich were from gynogenetic fish (crucian carp) and amphimictic fishes (red carp, redgoldfish and sex--reversal red carp) respectively in the eggs of gynogenetic crucian carp, itwas preliminarily revealed that there existed selective inhibiting actions of the primarycontrol in the eggs of crucian carp for inhibiting the development of the two types of spermnuclei. To homologous sperms, the primary control showed weak effect, thus leading tothe decondensation of homologous sperm nuclei at different degrees in the eggs of cruciancarp. But to heterologous sperms, the primary control showed strong effects, resulting in thetotal inhibition of the development of heterologous sperm nuclei. Moreover, our experimentalresults also showed that the different developmental behavior of the two types of spermnuclei might have a great relationship to the changes or the sex ratio in the population ofgynogenetic crucian carp. The infiltration of 'the genetic materials in sperm nuclei' intothe female nucleus at random might play an important role in male emergence in the naturallygynogenetic population of crucian carp.
