In vitro maturation of human oocytes maintaining good development potential for rescue intracytoplasmic sperm injection with fresh sperm

BACKGROUND The outcomes of the use of commercial in vitro maturation(IVM)medium to culture immature oocytes obtained from conventional ovulation induction,followed by rescue intracytoplasmic sperm injection(RICSI),are not ideal.It is thus difficult to widely adopt this approach in clinical practice.Therefore,it is necessary to explore methods for improving the clinical outcome of IVM.AIM To study the effect of sperm on the developmental potential of in vitro-matured oocytes in conventional culture.METHODS This was a retrospective study of patients whose immature oocytes were harvested from conventional oocyte stimulation cycles and underwent ICSI at our hospital between June 2018 and August 2020.RICSI was performed using sperm collected on the day of oocyte harvest(old)and sperm collected on the day of RICSI(fresh)and oocytes matured in vitro after 24 h of culture in conventional medium.The rates of in vitro oocyte maturation,normal fertilization,normal cleavage,day-3 top-quality embryos,and useful blastocyst formation were compared between the two groups.RESULTS In total,102 germinal vesicle(GV)-stage immature oocytes were cultured in the old sperm group.In the fresh sperm group,122 GV-stage immature oocytes were collected and cultured in vitro for 24 h.There were no significant differences in the general conditions of males and females between the two groups(P>0.05).The oocyte maturation,normal fertilization,and normal cleavage rates of the old and fresh groups were 51.0%vs 55.7%,61.5%vs 64.7%,and 93.8%vs 93.2%,respectively.None of the rates differed significantly(P>0.05)between the two groups.However,the day-3 top-quality embryo and useful blastocyst rates of the old and fresh sperm groups were 16.6%vs 63.4%;6.67%vs 34.6%,respectively.The day-3 top-quality embryos and useful blastocyst rates of the old sperm group were significantly lower than those of the fresh group(P<0.05).CONCLUSION In vitro maturation with conventional culture medium combined with the use of fresh sperm collected on the day of RICSI is an easy-to-implement strategy for patients whose oocytes are completely or mostly immature.

Fertilization of in vitro matured human oocytes by intracytoplasmic sperm injection (ICSI) using ejaculated and testicular spermatozoa

Aim: To evaluate the fertilization competence of spermatozoa from ejaculates and testicle when the oocytes were matured in vitro following intracytoplasmic sperm injection (ICSI). Methods: Fifty-six completed cycles in 46 women with polycystic ovarian syndrome were grouped according to the semen parameters of their male partners. Group 1 was 47 cycles that presented motile and normal morphology spermatozoa in ejaculates and Group 2 was the other nine cycles where male partners were diagnosed as obstructive azoospermia and spermatozoa could only be found in testicular tissue fragment. All female patients received minimal stimulation with gonadotropin. Immature oocytes were matured in vitro and inseminated by ICSI. The spermatozoa from testes were retrieved by testicular fine needle aspiration. Results: A total of 449 and 78 immature oocytes were collected and cultured for 48 hours, 75.5 % (339/449) and 84.6 % (66/78) oocytes were matured in Groups 1 and 2, respectively. The percentage of oocytes achieving normal fertilization was significantly higher in Group 1 than that in Group 2 (72.9 % vs. 54.5 %, P < 0.05). There were no significant differences in the rates of oocytes cleavage and clinical pregnancies in these two groups [87.4 % (216/247) vs. 88.9 % (32/36); 21.3 % (10/47) vs. 44.4 % (4/9)]. A total of 15 babies in the two groups were healthy delivered at term. Conclusion: It appears that IVM combined with ICSI using testicular spermatozoa can produce healthy infants, while the normal fertilization rate of in vitro matured oocytes after ICSI using testicular spermatozoa was significantly lower than using the ejaculated spermatozoa.

Fertilization of IVF/ICSI Using Sibling Oocytes from Couples with Subfertile Male or Unexplained Infertility

The significance of the performance of conventional in vitro fertilization and intracytoplasmic sperm injection (IVF/ICSI) using sibling oocytes from couples with subfertile male or unexplained infertility was evaluated. A total of 410 sibling oocyte cumulus-corona complexes (OCCC) from 21 couples with subfertile male (group A) and 11 unexplained infertile couples (group B) were randomly divided, in order of retrieval, into two groups inseminated either by conventional IVF or by ICSI. The treatment outcomes and the influence of infertility factors on fertilization in each group were compared. The results showed that although the two pronuclear (2PN) fertilization rate per injected sibling oocytes was significantly higher after ICSI (group A: 68.2 %±28.8 %; group B: 66.2 %±24.9 %) than after conventional IVF (group A: 41.8 %±32.7 %; group B: 40.1 %±22.1 %), the other variables studied included: the fertilization rates of per allocated sibling oocytes IVF/ICSI, the fertilization rates of sibling oocytes IVF/ICSI after excluding failed IVF fertilization cycles, as well as the cleavage rates of normal fertilization were not statistically significant (P>0.05). Similarly, though the total fertilization failure rate in the IVF group (group A: 42.9 %; group B: 36.4 %) was significantly higher than in the ICSI group (group A: 4.8 %; group B: 0), we did not cancel cycles due to the normal fertilization of sibling oocytes. Embryo transfer was possible in all 32 couples. There were 10 clinical pregnancies in the two groups. We also discovered a possible association between some semen parameters and sperm functions of group A, and women age and duration of infertility of group B and fertilization. It is suggested that adoption of the split IVF/ICSI technology in the above cases may help eliminate fertilization failures. This is also a useful method to investigate the effect of single factor on the employment of assisted reproductive technology.

Sperm counts and sperm sex ratio in male infertility patients

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.

Role of ICSI in Non-male Factor Cycles as the Number of Oocytes Retrieved Decreases from Four to One

This study aimed to investigate whether intracytoplasmic sperm injection（ICSI） shows an advantage over in vitro fertilization（IVF） in non-male factor cycles as the number of oocytes retrieved decreases from four to one.We undertook a retrospective analysis of 1305 IVF/ICSI cycles of non-male factor in which four or fewer oocytes were retrieved.Comparisons were made between conventional IVF（CI） and ICSI when one,two,three or four oocyte（s） were retrieved.Primary outcomes including normal fertilization rate,proportion of embryos per obtained oocyte,cycle cancellation rate,implantation rate,clinical pregnancy rate（PR）,live birth rate（LBR）,cumulative PR and cumulative LBR were evaluated.The results showed that the normal fertilization rate（72.5% vs.50.0%） and the proportion of embryos per obtained oocyte（72.5% vs.55.0%） were significantly increased in one oocyte retrieved cycles in ICSI group as compared with CI group.However,the proportion of embryos per obtained oocyte was markedly decreased in ICSI group when three（52.3% vs.61.3%） or four（56.9% vs.64.0%） oocytes were retrieved.The implantation rates,clinical PRs,LBRs,cumulative PRs and cumulative LBRs in CI group were comparable to those in ICSI group when one,two,three or four oocyte（s） were retrieved.In conclusion,ICSI doesn＇t show advantages over IVF in low oocyte yield cycles of non-male factors,even when only one oocyte was retrieved.Key words

Effects of MⅡ stage oocytes zona pellucida birefringence on pregnancy outcome

Objective:To explore the effects of different MⅡstage oocytes zona pellucida birefringence on pregnancy outcome.Methods:A total of 46 couples with infertile which induced by single cause received in-vitro fertilization treatment were analyzed retrospectively,and randomly divided into the high zona birefringence(HZB)/HZB group.HZB/low zona birefringeuce(LZB) group and LZB/LZB group according to different oocytes zona pellucida birefringence.Intracytoplasmic sperm injection outcome was analyzed and compared.Results:The proportion of HZB oocytes, implantation rate and the pregnancy rate were decreased in three groups(HZB/HZB group】HZB/ LZB group】LZB/LZB group)(P【0.05).But there was no significantly different between the number of oocytes and fertilization rate of these groups(P】0.05).Logistic regression analysis showed that factors allecl MⅡstage oocytes zona pellucida birefringence were age.basal FSH level and the LH level on the day of HCG injection.Age and KSH levels were negatively correlated with the single oocyte zona pellucida birefringence:While the LH level on the day of hCC injection was positively correlated with the single oocylc zona pellucida birefringence.Conclusions:The primary influence factors on MⅡstage oocytes zona pellucida are age.basal FSH level and the LH level on the day of hCG injection.The birefringence value of zona pellucida can affect the pregnancy outcome.

Estimating zona pellucida hardness under microinjection to assess oocyte/embryo quality: Analytical and experimental studies

The precise determination of zona pellucida (ZP) hardness is largely unknown due to the lack of appropriate measuring and modelling methods. In this study, we have used experimental and theoretical models to describe the mechanical behavior of a single oocyte cell to improve the assisted reproductive technology (ART) outcomes by assessing oocyte/embryo quality. This paper presents the development of: i) a microinjection model to estimate the force of ZP penetration, ii) a micropipette aspiration model to determine the corresponding hardness, and iii) an experimental procedure to generate the required data for these two models. Our results show that the estimated penetration force provides a performance target for the penetration process during intracytoplasmic sperm injection (ICSI), while the estimated corresponding hardness serves as an indicator of the extent of deformation sustained by the oocyte prior to penetration. Evaluation of these results shows that a routine assessment of ZP hardness under microinjection would allow for the identification of certain oocyte pools for which further manipulation is recommended in order to improve injection, hatching and finally ART outcomes.

Observation on Sperm Penetration Rate of Infertile Men with Varicocele at 1.5 to 2 Years after Varicolectomy

Objective To observe the sperm penetration rate among treated but 'unsuccessful' infertile men with varicocele Material & Methods Twenty nine infertile males with II°(n=17) or III°(n=12) varicocele were enrolled into this study. They underwent a varicolectomy, but their spouses had not achieved a pregnancy after 1.5~2 years of treatment. The sperm zona-free hamster oocyte penetration assay (SPA) was used to compare the sperm penetration rate (PR) before treatment and 1.5~2 years after treatment. Results After varicolectomy, enhanced PR were observed in 7 cases of the II°group and in 1 case of the III°group. However, the PR values of these 8 cases were still below 20% PR-level. Conclusion Among the treated but 'unsuccessful' men, some patients could obtain improvements on PR after varicolectomy. But PRs of men with III°grade varicele would still remain a low PR-level which indicate varicolectomy is ineffective in increasing PR among part of sever varicocele patients. SPA is a useful test for evaluating the fertilizing potential of treated infertile males with varicocele.

Oocyte quality improvement using a herbal medicine comprising 7 crude drugs

Maternal age is a significant factor in infertility treatment. Ovarian function and oocyte quality decrease with age, whereas the frequency of chromosomal abnormalities increases. In this study, improvement of oocyte quality and ovarian function were attempted using a herbal medicine comprising 7 crude drugs:Angelicae radix,Rehmanniae radix,Plantaginis semen,Lonicerae flos,Carthami flos,Ginseng radix, andCucurbita moschata Duch. Thirty-one women who repeatedly failed to conceive by intracytoplasmic sperm injection took the herbal medicine before breakfast and dinner from the start of menstrual cycle in the ovum pickup cycle. Average patient age was 38.5 ± 0.7 years, and the average ovum pickup frequency on the first dosage day was 7.9 ± 1.5. To analyze the effects of herbal medicine intake, the number of recovered and mature oocytes, their morphology and physical qualities, as well as the rates of fertilization, oocyte development, and pregnancy was compared before and after intake. The recovered and mature oocyte numbers, oocyte morphology and physical qualities, and fertilization rate were not significantly different before and after drug intake. However, the oocyte development rate was significantly higher(58.0%) after herbal medicine intake than before (32.5%;p = 0.0003). Moreover, the successful pregnancy rate was significantly higher after intake than before (6.9% versus 0%;p = 0.0111). Herbal medicine may constitute a useful adjunct to assisted reproductive technology in women.

回族及维吾尔族圆头精子症患者的基因诊断、精子超微结构观察和辅助生殖结局分析

目的探讨2例少数民族(P1回族、P2维吾尔族)圆头精子症患者的临床表型、精子特点、遗传学病因以及辅助生殖结局。方法分析2例少数民族圆头精子症患者的临床资料和各种精液检查参数,观察精子超微结构,并利用全外显子检测技术和qPCR检测分析患者的遗传学病因,采用卵胞质内单精子注射联合卵母细胞激活技术(ICSI+AOA)进行辅助生殖治疗,并观察其助孕结局。结果2例患者均存在DPY19L2基因109681 bp纯合缺失,其中P2患者的DPY19L2基因缺失来源于近亲结婚的父母。P1患者精子活力低下,精子DNA碎片率高,精子形态为100%圆头精子,电镜下发现精子顶体缺失,同时存在质膜、线粒体和微管等超微结构缺陷;P2患者精子活力及精子DNA碎片率均正常,精子形态为100%圆头精子,电镜下观察发现精子主要缺陷为头部小而圆伴随顶体缺失,质膜、线粒体和微管等细胞器结构损伤与超微结构缺陷少见。2例患者夫妇均接受ICSI+AOA助孕,ICSI受精率P1患者夫妇为62.5%,P2患者夫妇为75%,均成功获得临床妊娠。结论DPY19L2基因异常在不同民族背景的圆头精子症患者中都是主要的致病遗传学原因。圆头精子可同时存在质膜、线粒体和微管等细胞器结构损伤与超微结构缺陷。ICSI+AOA是圆头精子症患者的有效辅助生殖治疗。

深度学习在辅助生殖技术领域的应用进展

深度学习是人工智能领域一种机器学习方法,它模拟人类大脑神经网络的工作原理来解决复杂的问题,目前在医学领域已有许多重要的研究和应用,如影像诊断、生物医学数据处理、药物研发、个性化医疗等,提高了医疗诊断和治疗的准确性及效率。在辅助生殖领域,深度学习在干预过程中高效识别生长良好的胚胎、适宜的卵母细胞或精子,协助专业人员做出更为准确的选择,提高妊娠率,减少多胎妊娠风险。本文将综合归纳近5年深度学习在辅助生殖技术领域的最新应用进展,并对今后研究方向进行展望。

哺乳动物精卵识别及阻止多精入卵机制的研究进展

哺乳动物卵子的受精过程是由减数分裂产生的高度特化的精子和卵子之间进行相互识别和融合的过程,其中精子与卵子透明带和质膜的特异性识别是完成正常受精的关键。正常条件下,一个精子和一个卵母细胞进行特异性识别后融合才能形成合子,并完成一系列的转变,从而开启新个体的发育。而多个精子通过卵子透明带和质膜会造成多精入卵现象,导致胚胎发育失败。精子与卵子相遇后,精子表面蛋白与卵子透明带糖蛋白及质膜蛋白之间的特异性识别,是保障正常受精并阻止多精入卵的关键。文章围绕精子与卵子透明带蛋白和质膜上负责特异性识别的蛋白及其相关作用机制进行了综述,并对皮质反应、透明带反应和卵黄膜反应在去除卵子对应特异性蛋白方面的作用进行探讨,以期为家畜体外受精技术的发展提供理论支持和新的思路。

精子相关抗原9联合PSAD、fPSA/tPSA比值诊断PSA灰区前列腺癌的临床研究

目的:研究尿液中精子相关抗原9(SPAG9)含量联合血清中前列腺特异性抗原密度(PSAD)、游离前列腺特异性抗原(fPSA)/总PSA(tPSA)比值诊断PSA灰区前列腺癌的价值。方法:选择2018年1月—2022年12月期间在南通市第二人民医院门诊或住院收治的血清PSA水平处于灰区(4~10 ng/mL)的309例患者作为研究对象,根据前列腺穿刺术的病理结果分为前列腺癌组58例和前列腺良性组251例(对照组)。所有患者均在术前留取尿液并检测SPAG9含量,测定血清PSAD、fPSA、tPSA,计算fPSA/tPSA比值,比较两组间临床资料的差异,采用Logistic回归分析确定前列腺癌的相关因素,绘制受试者工作特征(ROC)曲线、计算曲线下面积(AUC)并分析各指标对前列腺癌的诊断价值。结果:前列腺癌组和对照组间患者的体质量、tPSA、白细胞计数、血红蛋白、血小板计数、总胆红素、白蛋白、肌酐、尿酸、前列腺体积的差异均无统计学意义(P>0.05);前列腺癌组患者的年龄、尿液SPAG9含量、血清fPSA/tPSA比值、PSAD均高于对照组,差异均有统计学意义(P<0.05);多因素Logistic回归分析显示,尿液SPAG9含量、血清fPSA/tPSA比值、PSAD是前列腺癌的影响因素;ROC曲线分析显示,尿液SPAG9含量、血清fPSA/tPSA比值、PSAD单独及联合均能诊断前列腺癌,3项指标联合的诊断效能理想,灵敏度和特异度分别为80.00%和80.88%。结论:尿液SPAG9可作为诊断PSA灰区前列腺癌的标志物,尿液SPAG9与血清fPSA/tPSA比值、PSAD联合检测对PSA灰区前列腺癌具有较好的诊断效能。

卵母细胞成熟度在高龄患者ICSI治疗结局中的影响研究

目的:探究高龄患者卵胞浆内单精子注射(ICSI)中卵母细胞成熟度对其治疗结局的影响。方法:选取赣州市妇幼保健院于2019年1月—2022年12月收治的进行ICSI助孕治疗的142例高龄患者作为研究对象,根据患者卵母细胞成熟度(成熟卵母细胞与取卵获得卵母细胞数之比)将患者分为A组(成熟度>80%,n=104)、B组(60%<成熟度≤80%,n=28)、C组(成熟度≤60%,n=10)。比较三组获卵情况及妊娠结局[受精率、双原核(2PN)受精率、优质胚胎率、囊胚形成率、累计临床妊娠率]。结果:三组获卵率、平均获卵数、≥14 mm卵泡数、MⅡ卵率比较,差异均有统计学意义(P<0.05)。A组获卵率、平均获卵数、≥14 mm卵泡数、MⅡ卵率均显著高于B组与C组(P<0.05)。三组受精率、优质胚胎率、囊胚形成率、累计妊娠率比较,差异均无统计学意义(P>0.05)。三组2PN受精率比较,差异有统计学意义,且以A组的2PN受精率最高(P<0.05)。A组与B组的累计妊娠率均高于C组,差异均有统计学意义(P<0.05)。结论:高龄患者行ICSI治疗结局受卵母细胞成熟度的影响,卵母细胞成熟度低可对获卵情况、受精及胚胎发育造成负面影响。

45,X/46,XY混合性性腺发育不全患者采用卵母细胞捐赠获得活产1例及文献复习

目的:探讨45,X/46,XY混合性性腺发育不全的病因、诊断、治疗、受孕及分娩的临床特点,提高对此类患者的诊治及妊娠管理水平。方法:回顾性分析1例45,X/46,XY混合性性腺发育不全妊娠患者的临床资料并结合相关文献进行讨论。结果:通过患者第二性征发育不全、条索状性腺、染色体核型与社会性别不符等临床特征,结合性腺组织染色体畸变检测结果,确诊患者为45,X/46,XY混合性性腺发育不全,并给予“卵母细胞捐赠ICSI-ET治疗”获得活产。结合文献分析总结此类患者妊娠受孕、妊娠及分娩过程中的临床特点。结论:45,X/46,XY混合性性腺发育不全女性患者无生育能力,可通过卵母细胞捐赠获得妊娠,但此类孕妇的妊娠并发症的发病率以及异常分娩率均高于普通人群。明确诊断,加强妊娠风险评估,以改善围产结局。

Inhibition of mouse acrosome reaction and sperm-zona pellucida binding by anti-human sperm membrane protein 1 antibody

Aim： To investigate the possible functions of human sperm membrane protein （hSMP-1） in the process of fertilization. Methods： A 576-bp cDNA fragment of HSD-1 gene coding for the extracellular domain of hSMP-1 was cloned and expressed. The localization of this protein on human and mouse sperm was determined by indirect immunofluorescent staining by using anti-recombinant hSMP-1 （anti-rhSMP-1） antibodies. Sperm acrosome reaction and spermzona pellucida （ZP） binding assay were carried out in 10-week-old BALB/c mice. Results： Recombinant hSMP-1 was successfully cloned and expressed. The expression of the native protein was limited on the acrosome of human and mouse sperm. Treatment of anti-rhSMP-1 antibodies significantly decreased the average number of sperms bound to each egg. Meanwhile, the percentage of acrosome reaction was decreased in comparison to pre-immune control after treatment with anti-rhSMP-1 （P 〈 0.05）. Conclusion： The results suggest that anti-rhSMP-1 antibody inhibited mouse acrosome reaction and sperm-ZP binding.

Protein tyrosine phosphorylation of the human sperm head during capacitation： immunolocalization and relationship with acquisition of sperm-fertilizing ability

The occurrence of tyrosine phosphorylation （TP） in the sperm head during capacitation has been poorly investigated, and no data exist on the relationship of its dynamics with the acquisition of sperm fertilizing ability. This study localized TP of head proteins in human spermatozoa during capacitation and explored its relationship with acquisition of the ability to display progesterone （P）-stimulated acrosome reactions （ARs） and to penetrate zona-free hamster oocytes. By immunofluorescence, TP immunoreactivity was revealed in the acrosomal region of formaldehyde-fixed/unpermeabilized samples, whereas it was abolished in fixed/permeabilized samples, in which TP immunoreactivity was high in the principal piece. No TP immunoreaetivity was detectable in unfixed spermatozoa. Head TP immunoreactivity was localized externally to the acrosome, close to the cytoplasmic membrane, as assessed by transmission electron microscopy. The increase in head TP was an early event during capacitation, occurring within 1 h in capacitating conditions. At this time, the P-stimulated ARs were also increased, whereas egg penetration was as poor as in uncapacitated spermatozoa. At 5 h of capacitation, the extent of neither head TP nor the P-induced ARs were greater than that at 1 h, whereas egg penetration had significantly increased. Seminal plasma inhibited head TP, P-induced ARs and egg penetration. None of these inhibitory effects, unlike those on tail TP, were prevented by the cAMP analogue dbcAMP （N,2-O-dibutyryladenosine 3＇,5＇-cyclic monophosphate）. In conclusion, head TP is a subsurface event occurring early during capacitation and is closely related to acquisition of the ability to display P-stimulated ARs, whereas the ability to fuse with oolemma and to decondense is a later capacitation-related event.

Hemizona Assay in Rhesus Monkeys:Influences of SpermMotility and Oocyte Maturational Stages onSperm/Egg Binding

The zona pellucidae is the first important position in sperm/oocyte interactions.Sperm binding to the zona pellucidae is an initial and critical step in fertilization,which is relevant to both of sperm motility and oocyte maturational stage. However,until recently there was no ideal model to predict fertilization potential of spermand to reveal the mechanism of sperm/oocyte interactions. The hemizona assay (HZA)was first established in human in vitro fertilization(IVF) by using the two matchingzona hemispheres with functional equality which provides many obvious advanages incomparative research of sperm/oocyte binding and interaction. In human IVF, the re-sults have certainly verified the feasibility of the HZA as a test to predict

Sperm speed is associated with sex bias of siblings in a human population

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,

Secondary sex ratio of assisted reproductive technology babies

Objective: To assess the secondary sex ratio (SSR) of assisted reproduction technology babies within a fertility clinic in Melbourne, Australia. Methods: A retrospective cohort study was conducted on 3369 babies who were born following single embryo transfer between 2011 and 2016. Variables examined included embryo creation date, maternal and paternal ages, maternal body mass index (BMI), type of infertility, sperm parameters, fertilization method, type of embryo and stage of transfer. Multivariate regression analysis was performed on the data set using STRATA V9.2. Results: More males were found to be born to embryos created in summer (adjusted odds ratio=1.46, 95% confidence interval: 1.08-1.95;P=0.01). Lower BMI of mother (≤30 kg/m 2) and younger age of parents (≤35 years) were associated with an increase in SSR (50.1% vs. 47.1%;50.6% vs. 48.8%;50.0% vs. 48.9%) respectively. Decreased SSR value was associated with primary subfertility, using in-vitro fertilization procedure and fresh embryo compared to those with secondary subfertility, using intracytoplasmic sperm injection procedure and thawed embryo (49.3% vs. 50.6%;47.1% vs. 50.8%;49.4% vs. 50.1%) respectively. Conclusions: The fertilization methods, type of embryo, stage of embryo transfer, parameters of the sperm and status of subfertility do not significantly affect the SSR. SSR is affected by the seasonality, maternal age, and BMI.