Exposure to bisphenol A (BPA) in Wistar rats reduces sperm quality with disruption of ERK signal pathway.

Bisphenol A (BPA) is an estrogenic environmental toxin widely used in the production of plastics and ubiquitous human exposure to this chemical has been proposed to be a potential risk to human health. Exposure to BPA can negatively impact sperm quality. However, the mechanism remains largely unknown.

Single or double semen samples: the dilemma in epidemiological studies on semen quality.

Study Question: Is it necessary to collect more than one semen sample from each individual in epidemiological studies?

Summary Answer: Single semen samples can be used in model construction as long as the model adjusts for major relevant covariates.

What Is Known Already: If a series of semen samples are taken from one individual at different times, significant intra-individual variation may exist.

Study Design, Size, Duration: A population-based cross-sectional study was conducted from 1 December 2000 to 20 November 2002.

Induced abortion and breast cancer: results from a population-based case control study in China.

Aim: To determine whether induced abortion (IA) increases breast cancer (BC) risk.

Materials And Methods: A population-based case-control study was performed from Dec, 2000 to November, 2004 in Shanghai, China, where IA could be verified through the family planning network and client medical records. Structured questionnaires were completed by 1,517 cases with primary invasive epithelial breast cancer and 1,573 controls frequency- matched to cases for age group.

[The influence of smoking on the routine parameters of semen quality].

Objective: To explore the effect and heaviness of smoking on the routine parameters of semen quality.

Methods: A total of 727 eligible subjects including 421 smokers and 306 nonsmokers were selected in 2004 - 2006 in Hebei, Shanxi, Guizhou, Zhejiang and Shandong provinces. Data on background information, general demographic characteristics, exposure to smoking and related confounding factors were obtained through a questionnaire survey.

[The influence of high birth weight on the blood pressure during childhood - a cohort study].

Objective: To explore the effects of high birth weight (HBW) on blood pressure (BP) during childhood.

Methods: A total of 1435 couples with high or normal birth weight were selected from a birth cohort who were born between 1993 and 1995 in Wuxi, China and, followed between 2005 and 2007. A questionnaire survey was conducted, with their height, weight and blood pressure measured.

Effect of interpregnancy interval after a mifepristone-induced abortion on neonatal outcomes in subsequent pregnancy.

Background: The study evaluated effects of interpregnancy interval (IPI) on neonatal outcomes after mifepristone-induced abortion in the first pregnancy.

Study Design: This observational cohort study, conducted from 1998 to 2001 at antenatal clinics in Shanghai, Beijing, and Chengdu, China, included 4682 nulliparous women with one mifepristone-induced abortion in their first pregnancy, who were enrolled and followed up until delivery. We compared neonatal outcomes among women with different IPIs between their mifepristone-induced abortion and subsequent pregnancy.

Mifepristone-induced abortion and vaginal bleeding in subsequent pregnancy.

Background: The aim of this study is to explore the effect of first-trimester mifepristone-induced abortion on vaginal bleeding in subsequent pregnancy.

Study Design: This observational cohort study was conducted during 1998-2001 at antenatal clinics in Beijing, Chengdu, and Shanghai, China. The study enrolled 4,931 women with one previous mifepristone-induced abortion, 4,925 women with no history of induced abortion, and 4,800 women with one previous surgical abortion and followed them through pregnancy and childbirth.

Turning point of age for semen quality: a population-based study in Chinese men.

Objective: To explore the relationship between age and semen quality in Chinese men.

Design: Population-based cross-sectional study.

Setting: The Department of Reproductive Epidemiology and Social Science, Shanghai Institute of Planned Parenthood Research, People's Republic of China.

Effects of caesarean section on maternal health in low risk nulliparous women: a prospective matched cohort study in Shanghai, China.

Background: Rates of caesarean section are progressively increasing in many parts of the world. As a result of psychosocial factors there has been an increasing tendency for pregnant women without justifiable medical indications for caesarean section to ask for this procedure in China. A critical examination of this issue in relation to maternal outcomes is important.

Urine bisphenol-A (BPA) level in relation to semen quality.

Objective: To determine whether urine bisphenol-A (BPA) levels are associated with lower semen quality.

Design: Cohort study.

Setting: Four regions in China where high exposure to BPA in the workplace existed.

Mifepristone-induced abortion and duration of third stage labour in a subsequent pregnancy.

To evaluate the impact of mifepristone-induced abortion (MA) on the duration of third stage labour in a subsequent pregnancy, an observational cohort study was conducted from 1998 to 2001 at antenatal clinics in Shanghai, Beijing and Chengdu, China. A total of 4925 pregnant women with no history of induced abortion (NA) and 4931 pregnant women with one previous MA were enrolled and followed until delivery. Of these, 5139 women who delivered singletons vaginally were used in the present analyses, including 2614 with NA and 2525 with a history of MA.

[Association between age and quality of semen in Chinese males with normal fertility].

Objective: To explore the association between age and variables of semen in Chinese males with normal fertility.

Methods: The population size under study would consist of 946 fertile male volunteers from 6 provinces of China, aged between 20 and 59. Semen quality was analyzed by hand on site and background information was obtained through structured questionnaire.

[A case-control study on the association of RFC-1 polymorphism and cervical cancer].

Objective: To evaluate the possible association between RFC-1 polymorphism and cervix carcinoma, as well as the interaction between polymorphism and human papilloma virus16 (HPV16).

Methods: Based on a hospital-based case-control study, 107 cases which were diagnosed as cervical cancer pathematologically and 107 controls with hysteromyoma, were selected by frequency, matched with age and habitation. HPV16 and RFC-1 A80G polymorphism were detected by special PCR and RFLP.

Mifepristone-induced abortion and placental complications in subsequent pregnancy.

Background: The aim of the study was to explore the effect of first-trimester mifepristone-induced abortion (MA) on placental complications in subsequent pregnancy.

Methods: Two cohorts of nulliparous pregnant women were recruited in China during early pregnancy, one with a history of one MA and the other with no abortion (NA). Women were followed up until delivery.

Reference values of semen parameters for healthy Chinese men.

Aims: To establish reference values of semen parameters in a residential, geographic, and age representative sample of healthy Chinese men.

Methods: From a national study of 1,191 healthy Chinese men, semen samples were analyzed from 105 subjects whose wives or partners were pregnant within the 12 months prior to the date when the semen sample was taken.

Results: The means, fifth percentiles, and percentages lower than the WHO criteria for semen parameters were, respectively: 75.

[Analysis on the expression of human papillomavirus type 16 E2 and E6 oncogenes and disruption of E2 in cervical cancer].

Objective: To evaluate the roles of expression and early protein E2 and E6 load of human papillomavirus type 16 (HPV16) on cervical cancer in order to explore the relation between disruption of E2 and development of cervical cancer.

Methods: A case-control study was conducted, including 141 cervical cancer patients as cases who had been diagnosed by cytological approaches and histological approaches in Shanxi province Tumor Hospital, China. Two type of controls including 137 hospital controls with hysteromyoma by cytology or histology and eligible 129 controls from 1582 healthy women in the community who took part in community-organized physical examination with neither CIN2-3 nor invasive cancer, nor other gynecologic diseases were recruited.

[Study on the effect of a community-based early education and service program regarding intelligence development of infants].

Unlabelled: Study on the effect of a community-based early education and service program regarding intelligence

Objective: To assess the effect on a community-based early education and service programs regarding the development of infants' intelligence.

Methods: A community-based intervention study was carried out among 359 infants and their families. Base-line survey were carried out when infants reached their one month, where after infants and their families in the intervention group received instructions and services focused on baby fostering and intelligence development.

Effectiveness of a school-based AIDS education program among rural students in HIV high epidemic area of China.

Purpose: To evaluate the feasibility and effectiveness of a life-planning skills training program using participatory methods among rural senior high school students in Shangcai County, Henan Province, China.

Methods: The study was a quasi-experimental study conducted in three Shangcai County senior high schools with comparable socioculture-economic and demographic characteristics (two interventions and one control). The intervention, a life-planning skills program that uses participatory training methods, combining information education with effective skills building, was provided to all first-grade students (14-18 years old; 87% of them are between 15 and 17 years old) in the intervention group from October 2003 to December 2003.

Do reproductive hormones explain the association between body mass index and semen quality?

Aim: To examine whether reproductive hormones play a role in the association between body mass index (BMI) and semen quality.

Methods: Semen quality and testosterone (T), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol (E(2)) were evaluated in 990 fertile males with age 38.9 +/- 9.

[Association between endogenous hormones, hormone receptors and cervical cancer].

Objective: To explore the relationship between the levels of estrogen (E2) and progestogen (P), expression of estrogen receptor (ER) and progesterone receptor (PR) and cervical cancer.

Methods: A case-control study with hospital and community controls was employed. The levels of serum estrogen and progesterone were detected by enzyme linked immunosorbent assay (ELISA) for 141 cervical cancer cases, 137 uterine myoma patients as controls and 129 health women as controls.

Can the Internet be used effectively to provide sex education to young people in China?

Purpose: To assess the feasibility and effectiveness of sex education conducted through the Internet.

Methods: Two high schools and four colleges of a university in Shanghai were selected as the research sites. Half of these were assigned to the intervention group and the other half to the control group.

[Relationship between contraceptive use behavior and related knowledge and cognition among vocational high school students].

Objective: To study the relationship between contraceptive use behaviors and related knowledge and cognition among vocational high school students.

Methods: A computer-administrated anonymous cross-sectional survey was conducted among grade one students from three vocational high schools in a district of Shanghai. Based on Health Belief Model, four cognition indexes including perceived benefits, barriers, sex behavior related risks and self-efficacy were applied.

[Prospective observational study on the effects of caesarean section on breastfeeding].

Objective: To study the effects of caesarean section on breastfeeding.

Methods: Six hundred and two [301 cases was caesarean section (caesarean section group) and 301 cases was vaginal delivery (vaginal delivery group)] nulliparas were interviewed face-to-face at antepartum and postpartum in an indication-matched prospective study.

Results: There was a significantly lower postpartum prolactin (PRL) level in the caesarean section group (8.

Do Ureaplasma urealyticum infections in the genital tract affect semen quality?

Unlabelled: To investigate the relationship between Ureaplasma urealyticum (UU) infection and semen quality.

Methods: From 2001 to 2003, 346 eligible patients aged 20-45 years were invited from two hospitals in Shanghai, China, to participate in an investigation which included questionnaires about general and reproductive health, an external genital tract examination, UU culture and semen analysis. Multiple linear regression models were used to examine whether UU had a significant effect on semen quality after adjustment for confounding factors.

DDT serum concentration and menstruation among young Chinese women.

High DDE and DDT concentrations were found to be associated with shortened menstrual cycle length in Laotian immigrants to the United States. We examined this issue in a sample of young Chinese women. A total of 60 women aged 20-24 years were enrolled in three maternal and child health clinics (20 from urban, 20 from suburban, 20 from rural) in Shanghai, China, and vicinity, in 1998.