Prevalence of late-onset hypogonadism among middle-aged and elderly males in China: results from a national survey / 亚洲男科学杂志(英文版)

This study aimed to propose an operational definition of late-onset hypogonadism (LOH) that incorporates both clinical symptoms and serum testosterone measurements to evaluate the prevalence of LOH in aging males in China. A population-based sample of 6296 men aged 40 years-79 years old was enrolled from six representative provinces in China. Serum total testosterone (TT), sex hormone-binding globulin (SHBG), and luteinizing hormone (LH) were measured and free testosterone (cFT) was calculated. The Aging Males' Symptoms (AMS) scale was used to evaluate the LOH symptoms. Finally, 5078 men were included in this analysis. The TT levels did not decrease with age (P = 0.59), and had no relationship with AMS symptoms (P = 0.87 for AMS total score, P = 0.74 for ≥ 3 sexual symptoms). The cFT levels decreased significantly with age (P < 0.01) and showed a negative association with the presence of ≥ 3 sexual symptoms (P = 0.03). The overall estimated prevalence of LOH was 7.8% (395/5078) if a cFT level <210 pmol l

Correlation of sperm DNA fragmentation index with age and semen parameters in infertile men / 中华男科学杂志

<p><b>Objective</b>To explore the correlation of the sperm DNA fragmentation index (DFI) with age, sperm concentration and sperm motility in infertile men.</p><p><b>METHODS</b>We collected semen samples from 531 infertile males in our hospital from January 2016 to June 2017. We determined the semen parameters using the computer-assisted semen analysis system, measured the sperm DFI by sperm chromatin structure assay, and analyzed the correlation of the sperm DFI with the age, sperm concentration and sperm motility of the patients.</p><p><b>RESULTS</b>With the increase of age, the infertile males showed a significantly decreased proportion of the sperm with a DFI ≤15% and elevated proportion of the sperm with a DFI ≥25%, with a positive correlation between age and sperm DFI (r = 0.653, P < 0.01). With the increase of sperm concentration and motility, however, the proportion of the sperm with a DFI ≤15% was remarkably increased while that of the sperm with 15%<DFI<25% and ≥25% markedly reduced, both sperm concentration and motility negatively correlated with the sperm DFI (r = －0.246, P < 0.01 and r = －0.406, P < 0.01).</p><p><b>CONCLUSIONS</b>The sperm DFI is significantly correlated with age, sperm concentration and sperm motility, and therefore can be used as an important index for the evaluation of semen quality. A comprehensive analysis of the sperm DFI and semen parameters may contribute to an accurate assessment of male fertility.</p>

Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males / 中华男科学杂志

Objective@#To explore the longterm influence of vasectomy on the levels of serum androgens in aging males.@*METHODS@#Using stratified random sampling, we conducted a questionnaire survey and physical examinations among 437 adult males aged ≥40 years, 232 with and 205 without the history of vasectomy. In addition, we measured the levels of serum total testosterone (TT), sexhormone binding globulin (SHBG), calculated free testosterone (cFT), testosterone secreting index (TSI), free testosterone index (FTI), and luteinizing hormone (LH).@*RESULTS@#Compared with the nonvasectomy group, the vasectomy group showed significantly increased levels of serum TT (［16.01±5.41］ vs ［17.39±6.57］ nmol/L), SHBG (［58.91±36.89］ vs ［70.28±40.90］ nmol/L), and LH (［8.86±6.49］ vs ［10.85±11.73］ IU/L) (all P0.05), nor after adjustment for relevant factors in TT (β: 1.015, 95% CI: －0.180－2.210), SHBG (β: 5.118, 95% CI: －2.069－12.305), cFT (β: 0.003, 95% CI: －0.011－0.018), FTI (β: －0.012, 95% CI: －0.035－0.011), TSI (β: 0.138, 95% CI: －0.131－0.407), and LH (β: 1.011, 95% CI: －0.811－2.834) (all P>0.05).@*CONCLUSIONS@#Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males.

Induced pluripotent stem cells in spermatogenesis: Progress in current studies / 中华男科学杂志

Spermatogenesis is a complex process. Current knowledge about human spermatogenesis is mainly based on the mouse model while little is known about the initial stage of this fundamental process in humans. The establishment of the model of spermatogenesis in vitro may contribute to an overall understanding of male germ cell development, an insight into the mechanisms of infertility, and clinical management of male infertility. This review summarizes current knowledge about the generation of germ cell-like cells from induced pluripotent stem cells (iPSCs) in vitro and discusses the potential application of iPSCs in the treatment of male infertility.

Expression of Attractin in male reproductive tract of human and mice and its correlation with male reproduction / 华中科技大学学报（医学）（英德文版）

The expression of Attractin mRNA and protein in testis and semen of human and male mice was investigated. Human testis and semen samples were all collected from Reproductive Center of Renmin Hospital, Wuhan University in December, 2012. Testis samples were collected from 7 cases of obstructive azoospermias when they were subjected to diagnosed testis biopsy, and 30 normal human semen samples were obtained from those cases of semen analysis. Adult mice testis tissues were obtained from 10 2-month-old male BALB/c mice, and 60 male mice at different ages were classified into 10 groups (day 1, 5, 10, 15, 21, 28, 35, 42, 56, and 120 respectively, n=6 each). The expression of Attractin mRNA and protein in testis was detected by RT-PCR and Western blotting respectively. Human semen samples were centrifuged into sperm plasma (SP) and sperm extract (SE), and mice sperm samples were collected from the epididymis of 10 adult male BALB/c mice. Western blotting was used to determine the Attractin protein expression level. Attractin mRNA and protein were expressed in the testis of both patients with obstructive azoospermias and adult Bcl/B mice. Quantitative RT-PCR revealed that no Attractin mRNA was detectable in day 1 male BALB/c mice group. The Attractin mRNA and protein levels were low on the day 10, and increased with age until day 56. On the day 120, the expression levels of Attractin were decreased. As for human semen samples, Attractin protein was expressed in both SP and SE, but didn't exist in samples from the epididymis of male BALB/c mice. It was suggested that Attractin acted as a novel active substance and was involved in male reproduction in both human and BALB/c mice, but it exerted a different expression profile in different mammal species.

Screening results and causes of uncompleted donation process in 1 145 sperm donors / 中华男科学杂志

<p><b>OBJECTIVE</b>To improve the reception and recruitment of sperm donors in sperm banks in China, and solve the problem of insufficiency in sperm donation.</p><p><b>METHODS</b>We reviewed the recruitment of 1 145 men for sperm donation in the Human Sperm Bank of Hubei Province from September 2011 to April 2012, analyzed the reasons for those not included, and interviewed those included but unwilling to donate sperm.</p><p><b>RESULTS</b>Among the 1 145 recruits, 551 (48.12%) were students and 594 (51.88%) were other individuals. After the first semen screening, 503 (43.93%) quitted, including 202 students (36.66% of the students recruited) and 301 others (50.67% of the other individuals recruited). After the second semen screening, 432 (37.73%) were excluded, and another 45 (3.93%) excluded after laboratory examination, including 16 cases of mycoplasma positive. Totally, 165 recruits (14.41%) passed the semen screening and laboratory examination, but only 144 of them (87.27%) completed, while the other 21 (12.73%) failed to complete the whole donation process.</p><p><b>CONCLUSION</b>Low rates of screening qualification and donation process completion are common problems in human sperm banks. The rate of qualified sperm donors can be increased and the operational cost of the human sperm bank can be reduced by enabling the recruits to accomplish the whole donation process. Explanation at the reception, later interview with the recruits, and donors' trust in the sperm bank play important roles in raising the completion rate of sperm donation process.</p>

Expression of Attractin in male reproductive tract of human and mice and its correlation with male reproduction / 华中科技大学学报（医学）（英德文版）

The expression of Attractin mRNA and protein in testis and semen of human and male mice was investigated. Human testis and semen samples were all collected from Reproductive Center of Renmin Hospital, Wuhan University in December, 2012. Testis samples were collected from 7 cases of obstructive azoospermias when they were subjected to diagnosed testis biopsy, and 30 normal human semen samples were obtained from those cases of semen analysis. Adult mice testis tissues were obtained from 10 2-month-old male BALB/c mice, and 60 male mice at different ages were classified into 10 groups (day 1, 5, 10, 15, 21, 28, 35, 42, 56, and 120 respectively, n=6 each). The expression of Attractin mRNA and protein in testis was detected by RT-PCR and Western blotting respectively. Human semen samples were centrifuged into sperm plasma (SP) and sperm extract (SE), and mice sperm samples were collected from the epididymis of 10 adult male BALB/c mice. Western blotting was used to determine the Attractin protein expression level. Attractin mRNA and protein were expressed in the testis of both patients with obstructive azoospermias and adult Bcl/B mice. Quantitative RT-PCR revealed that no Attractin mRNA was detectable in day 1 male BALB/c mice group. The Attractin mRNA and protein levels were low on the day 10, and increased with age until day 56. On the day 120, the expression levels of Attractin were decreased. As for human semen samples, Attractin protein was expressed in both SP and SE, but didn't exist in samples from the epididymis of male BALB/c mice. It was suggested that Attractin acted as a novel active substance and was involved in male reproduction in both human and BALB/c mice, but it exerted a different expression profile in different mammal species.

Antioxidative and antiapoptotic effects of the Attractin gene on Sertoli cells in mice / 中华男科学杂志

<p><b>OBJECTIVE</b>To evaluate the effects of Attractin (Atrn) silence on the anti-oxidative and anti-apoptotic abilities of TM4 Sertoli cells and its influence on the expressions of superoxide dismutase (SOD) and caspase6 in the cells.</p><p><b>METHODS</b>We observed the apoptotic indexes of TM4 Sertoli cells with normal expression (control), partial deletion, and complete deletion of the Atrn gene (psiRNA-TM4, psiAtrn-TM4, and mu-SC). We determined the mRNA and protein expressions of SOD and caspase6 by Q-PCR and Western blot, measured the SOD activity and malondialdehyde (MDA) contentby spectrophotometry, and detected the apoptotic index of the cells by TUNEL.</p><p><b>RESULTS</b>Compared with psiRNA-TM4, after inhibition of the Atrn expression, the Sertoli cells in the psiAtrn-TM4 and mu-SCgroups showed significantly decreased expressions ofSOD mRNA (70.76% and 92.58%) and protein (65.11% and 71.0%) (both P < 0.05). The levels of caspase 6 mRNA and protein were increased 5.28 and 3.40 times in the psiAtrn-TM4 and 2.97 and 2.50 times in the mu-SCgroup as compared with the normal control (both P < 0.05). Atrn deletion markedly increased the apoptotic indexes of the cells in the psiAtrn-TM4 and mu-SC groups by 16.22% and 22.03% (P < 0.05) and reduced the activity of SOD by 23.00% and 39.37% (P < 0.05); it also elevated the level of MDA by 155.22% (P < 0.05).</p><p><b>CONCLUSION</b>The Atrn gene exerts influence on the function of Sertoli cells in multiple ways, in which antioxidative stress and apoptosis regulation may play an important role.</p>

Proteins in sperm and seminal plasma associated with human sperm resistance to cryopreservation / 中华男科学杂志

<p><b>OBJECTIVE</b>To identify the proteins that could improve the resistance of human sperm to cryopreservation using comparative proteomics.</p><p><b>METHODS</b>A total of 31 semen samples from 10 donors were divided into a high recovery and a low recovery group. Differentially expressed proteins in sperm and seminal plasma were detected and compared between the two groups by two-dimensional differential gel electrophoresis and mass spectrometry.</p><p><b>RESULTS</b>Totally, 22 differentially expressed proteins were found in the two groups, 12 seminal plasma proteins, 9 sperm proteins, and 1 belonging to both. These identified proteins were involved in the maturation, movement, energy metabolism, DNA repair and other activities of spermatozoa.</p><p><b>CONCLUSION</b>Many proteins were identified in sperm and seminal plasma that might influence the resistance of human sperm to cryopreservation.</p>

Human sperm chromatin damage and its determination: an update / 中华男科学杂志

Human sperm chromatin damage is one of the common reasons for reduced male reproductive capacity, which is influenced by genetics, environment, lifestyle and other factors, as well as associated with male infertility and habitual abortion. Along with deeper insights into the structure and function of sperm chromatin, improvement and promotion of detection technology for its integrity, and wider application of assisted reproductive technology, sperm DNA damage has been recognized as an important new indicator for the evaluation of sperm quality, and has a great clinical significance in the assessment of male fertility and selection of assisted reproductive technology.

Application prospect of adult stem cells in male infertility / 中华男科学杂志

The study on stem cells is a hot field in biomedical science in recent years, and has furthered from laboratory to clinical application. Stem cells, according to their developmental stage and differential properties, can be divided into embryonic stem cells, induced PS cells and adult stem cells, among which, adult stem cells have already been applied to the clinical treatment of many systemic diseases. Currently, the study of spermatogonial stem cells and adult stem cells is in the front of the basic researches on the treatment of male infertility, but the time has not yet arrived for their clinical application. This paper outlines the application prospect of adult stem cells in male infertility.

Biological characteristics and application prospect of mesenchymal stem cells in male infertility / 中华男科学杂志

Mesenchymal stem cells (MSCs) are somatic stem cells capable of self-renewing and multipotent differentiation. They are also referred to as " seed cells" in tissue engineering. Recent years have witnessed great advances in the studies of the differentiative potential and paracrine function of MSCs, as well as in their clinical applications in several fields. As for their application in male infertility, researches are still in the stage of animal experiments. However, with deeper insights into their huge potential, novel and effective MSC-based therapies for male infertility will come into being in the near future.

Detecting testis- and epididymis-specific methylated promoters in human cell-free seminal DNA by MeDIP-qPCR / 中华男科学杂志

<p><b>OBJECTIVE</b>To establish a method of methyl-DNA immunoprecipitation (MeDIP)-real time quantitative PCR (qPCR) for detecting the promoter methylation level in cell-free seminal DNA (cfsDNA).</p><p><b>METHODS</b>We obtained cfsDNA samples from 6 normozoospermia men (the NZ group) and 6 post-vasectomy patients (the PV group), and mixed the samples from different individuals of each group, respectively. Then we made DNA fragments by ultrasonication, separated the methylated DNA fragments by MeDIP, and determined the methylation level of the promoters in cfsDNA by qPCR.</p><p><b>RESULTS</b>The methylation levels of the promoters PRAME, PEG10, MORC1, GML, HOXA5, DNMT3L, SNURF, MSH4, DAZ1 and CLPB were 14.93, 2.64, 0.69, 2.66, 17.50, 21.10, 5.98, 2.28, 13.50 and 3.86%, respectively, in the NZ group, obviously lower than 121.25, 73.62, 16.25, 42.90, 76.74, 112.40, 59.79, 25.85, 91.90 and 64.53% in the PV group. The results of MeDIP-qPCR for the methylation of PRAME, MORC1, GML, HOXA5, DNMT3L, SNURF, MSH4 and DAZ1 were coincident with the results of genome-wide promoter methylation microarray.</p><p><b>CONCLUSION</b>MeDIP-qPCR can quantitatively measure the promoter methylation level in cfsDNA, and effectively determine the testis- and epididymis-specific methylated promoters in human semen.</p>

Association of CFTR gene polymorphism with congenital bilateral absence of vas deferens in ethnic Han Chinese patients / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association between a 5T polymorphism in intron 8 of cystic fibrosis transmembrane conductance regulator (CFTR) gene and congenital bilateral absence of vas deferens (CBAVD) in Han Chinese males.</p><p><b>METHODS</b>Genomic DNA from 33 individuals with CBAVD and 99 azoospermic males with CBAVD were recruited. The 5T polymorphism was detected with PCR, TA cloned and sequenced.</p><p><b>RESULTS</b>CFTR gene mutations were identified in 17 (51.5%) of patients with CBAVD. In 3 patients (17.6%), the mutations were identified on both alleles. Nine CFTR gene mutations (9.1%) were detected in 99 azoospermic patients, for whom none had mutations on both alleles.</p><p><b>CONCLUSION</b>This study has confirmed molecular heterogeneity of CFTR mutations in CBAVD. For CBAVD patients without 5T mutations, other changes may be found in the same gene.</p>

Expression of heme oxygenase enzyme in the testis tissue and azoospermia / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the location of heme oxygenase (HO) enzyme in the human testis, and explore the correlation of the expression of HO enzyme with azoospermia by analyzing its different expression levels in the testes of nonobstructive azoospermia, obstructive azoospermia and normal men.</p><p><b>METHODS</b>We detected the location of the cells expressing HO enzyme in the human testis tissue using immunohistochemistry, determined the mRNA and protein expression levels of HO-1 and HO-2 in the testes of azoospermia patients and normal healthy men by RT-fluorescence quantitative PCR (RT-FQ-PCR) and Western blot, and explored the correlation of HO expressions with the pathogenesis of azoospermia.</p><p><b>RESULTS</b>HO-1 enzyme was expressed mainly in the Sertoli cells and HO-2 enzyme chiefly in the germ cells of the testis tissue. RT-FQ-PCR showed that the expression of HO-1 in the testis tissue was significantly lower in the nonobstructive azoospermia than in the normal and obstructive azoospermia groups (P < 0.05), with no significant difference between the latter two. Western blot revealed no obvious difference between the expression level of HO-1 protein and that of HO-1 mRNA. There were no differences in the expression level of HO-2 protein among the three groups.</p><p><b>CONCLUSION</b>The expression level of HO enzyme is significantly decreased in the testis tissue of nonobstructive azoospermia patients, and the expression of HO-1 protein is consistent with that of HO-1 mRNA. As HO-1 protects the testis tissue against various stress injuries through its antioxidant, anti-inflammatory and anti-apoptotic effects, its decreased expression level may be correlated with spermatogenic dysfunction, and therefore considered as a possible mechanism of nonobstructive azoospermia.</p>

A combined method for weighing human semen volume / 中华男科学杂志

<p><b>OBJECTIVE</b>To search for a method for the precise measurement of human semen volume so as to provide reliable evidence for clinical semen analysis.</p><p><b>METHODS</b>The volumes of 492 semen samples collected from 137 donors by Zhejiang Human Sperm Bank were measured respectively by three different methods including electronic balance weighing, volumetric cylinder measuring, and combination of the two methods above. With the combined measuring method, the semen weight was first obtained by electronic balance weighing, then the semen density determined by volumetric cylinder measuring, and lastly the semen volume figured out by a formula. Paired sample t-test was used to compared the combined method with electronic balance weighing and volumetric cylinder measuring.</p><p><b>RESULTS</b>The mean volume of the 492 semen samples obtained by the combined measuring method was (3.46 +/- 1.17) ml, significantly lower than (3.75 +/- 1.21) ml from electronic balance weighing (P < 0.05) and markedly higher than (3.22 +/- 1.16) ml from volumetric cylinder measuring (P < 0.05). The mean semen density of the 492 samples was (1.0928 +/- 0.0761) g/ml, and the mean weight of the residual semen in the container used in volumetric cylinder measuring was (0.269 +/- 0.122) g.</p><p><b>CONCLUSION</b>Semen volume measured by electronic balance weighing is higher while that obtained from volumetric cylinder measuring is lower than the actual value. An accurate semen volume can be achieved by the combined measuring method, which, therefore, deserves to be widely used both clinically and in researches.</p>

Expression of NOSTRIN in the testis tissue of azoospermia patients / 中华男科学杂志

<p><b>OBJECTIVE</b>To determine the expressions of endothelial nitric oxide synthase traffic inducer (NOSTRIN) and endothelial nitric oxide synthase (eNOS) in the testis tissue of azoospermia patients, and investigate their correlation with the pathogenesis of azoospermia.</p><p><b>METHODS</b>We detected the expressions of NOSTRIN and NOSTRIN mRNA by immunohistochemistry and RT-PCR respectively, determined the activity of eNOS by spectrophotometry, and measured the stable metabolic end product NO, NO2- / NO3-, by nitrate reductase assay in the testis tissues of 17 patients with idiopathic azoospermia (the azoospermia group) and 10 normal men (the normal group).</p><p><b>RESULTS</b>NOSTRIN and NOSTRIN mRNA were expressed in the spermatogonia, sertoli cells, stromal cells and vascular endothelial cells, more lowly in the azoospermia than in the normal group (0.312 +/- 0.076 versus 0.793 +/- 0.082, P < 0.01). The activity of eNOS was significantly increased in the idiopathic azoospermia patients ([33.727 +/- 3.58] U/mg) compared with the normal men ([17.69 +/- 3.84] U/mg) (P < 0.01). The level of NO2- / NO3- was significantly higher in the azoospermia than in the normal group ([48.56 +/- 8.49] micromol/L versus [25.37 +/- 9.61] micromol/L, P < 0.01). The expression of NOSTRIN showed a significant negative correlation with the activity of eNOS (r = -0.57, P < 0.01) as well as with the level of NO2- / NO3- (r = -0.61, P < 0.01) in the testis tissue of the idiopathic azoospermia patients.</p><p><b>CONCLUSION</b>The expression of NOSTRIN is decreased, while the activity of eNOS and the level of NO2- / NO3- increased in the testis tissue of azoospermia patients, which may be associated with the pathogenesis of azoospermia.</p>

A comparative study of sperm morphology evaluation criteria by the fifth and fourth editions of WHO Laboratory Manual / 中华男科学杂志

<p><b>OBJECTIVE</b>To compare the criteria of sperm morphology evaluation in the fifth edition of WHO Laboratory Manual for the Examination and Processing of Human Semen and those in the fourth edition, and to know the changes in the criteria of sperm morphology evaluation in the new edition.</p><p><b>METHODS</b>Nine technicians from Zhejiang Human Sperm Bank evaluated the morphology of 1 000 spermatozoa in 96 sperm morphological pictures according to the criteria in the fourth and fifth editions of WHO Laboratory Manual, respectively.</p><p><b>RESULTS</b>The percentage of morphologically normal sperm by the criteria of the fifth edition was (26.50 +/- 5.06)%, significantly higher than (11.39 +/- 3.17)% by the fourth edition (P < 0.05), while the rates of sperm head and tail defects based on the former were (64.26 +/- 7.66)% and (10.92 +/- 2.03)%, significantly lower than (76.11 +/- 8.18)% and (39.89 +/- 3.85)% according to the latter (P < 0.05). There were no significant differences in the rates of sperm midpiece defects and excessive residual cytoplasm by the fifth and fourth editions ([16.46 +/- 3.08]% vs [15.22 +/- 3.51 ]% and [4.24 +/- 1.66]% vs [3.87 +/- 1.68]%, P > 0.05).</p><p><b>CONCLUSION</b>The criteria of sperm morphology evaluation in the fifth edition of WHO Laboratory Manual are less strict than those in the fourth, and the percentage of morphologically normal sperm is higher according to the fifth edition.</p>

Failed fertilization after ICSI: causes and countermeasures / 中华男科学杂志

As a new technique for IVF, ICSI has a high rate of monospermy but cannot prevent all fertilization failures, of which the possible causes are poor oocytes or sperm, abnormal oocyte activation, and ICSI technical problems. Controlled ovarian hyperstimulation during IVF could increase the apoptosis of oocytes and subsequently induce fertilization failure. There are several methods for artificial activation in case of oocyte activation failure. Sperm-induced fertilization failure is mostly due to minute malformation of sperm, for which morphologically selective ICSI is generally employed. However, totally failed fertilization after ICSI remains a real challenge.

Survey an knowledge, attitude, practice related to contraception among college students in Beijing / 中华流行病学杂志

Objective To understand the current status and relative factors on knowledge, attitude, practice to contraception among college students in Beijing and to provide evidence for developing aimed contraceptive service and education in colleges. Methods Quantitative surveys were employed, questionnaire was conducted anonymously among 12 450 unmarried college students under informed consent. Results Among 12 129 students, acknowledgement of contraceptive knowledge among females was superior to males in college(P=0.000). Rates on the favor for unmarried sexual practice and 'sexual liberation' were 81.9% and 60.2% for males, comparing to 74.8% and 54.3% for females respectively. The prevalence rates for masturbation were 74.3% for males and 24.9% for females respectively. 18.4% of the male and 10.5% of the female students had ever experienced unmarried sexual intercourse. Among those students who had sexual experiences, 29.4% of the males had made their sex partners pregnant and 23.1% of the female students had experienced unexpected pregnancy. Statistical significance was found between males and females (P=0.000) in terms of attitudes and behaviors. 51.3% of the male and female students took contraceptive measures during the episode of first sexual intercourse. The excuses for not taking any measures would include: sexual intercourse happened incidentally, not interested in using condom, only one sexual experience would not cause pregnancy, etc. Conclusion The prevalence of unmarried sexual intercourse among college students had been rising. Among those who had experienced unmarried sexual intercourse, the rate of taking contraceptive measures was low and the incidence of unexpected pregnancy was high. It is urgent to strengthen the education and service programs on contraception among college students.