Teenage pregnancy in developed countries: determinants and policy implications.
Explore the source record for details and available documents.
Adolescent↗
SEARCH · Search PubMed
Results for “Contraceptive Distribution”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
East Asia review, 1976-7: Thailand.
Explore the source record for details and available documents.
Contraception↗
Polygyny and reproductive behavior in sub-Saharan Africa: a contextual analysis.
In this paper I examine the effect of polygyny on aggregate reproductive behavior. I argue that within countries there exist different polygyny regimes, each exhibiting a unique reproductive pattern. Using the 1988/1989 Kenya Demographic and Health Survey (KDHS1) data, I identify three distinct regimes: low-polygyny, mid-polygyny, and high-polygyny regimes. The results of the bivariate and multivariate analyses reveal strong differences in reproductive preferences and behaviors across polygyny regimes. High-polygyny regimes, for instance, maintain a value orientation that favors and encourages high reproductive performance. The force of this pronatalism operates equally for men and women; but whereas men in this regime attain their reproductive goals by marrying multiple wives, women attain theirs by maximizing their reproductive capabilities. This maximization occurs through early initiation of sexual/reproductive activity, universal marriage and minimal interruption of marriage, nonuse of contraception within a union, and a positive attitude toward high fertility.
Adolescent↗
Both inherited susceptibility and environmental exposure determine the low-density lipoprotein-subfraction pattern distribution in healthy Dutch families.
A lipoprotein profile characterized by a predominance of small, dense, low-density lipoprotein (LDL) particles has been associated with an increased risk of atherosclerosis. To investigate whether genetic factors are involved in determining this heavy LDL subfraction pattern, this study was undertaken with the aim of resolving the effects that major genes, multifactorial heritability, and environmental exposures have on the LDL subfraction pattern. In a random sample of 19 healthy Dutch families including 162 individuals, the distribution of the LDL subfraction pattern was determined by density gradient ultracentrifugation. For each subject a specific LDL subfraction profile was observed, characterized by the relative contribution of the three major LDL subfractions--LDL1 (d = 1.030-1.033 g/ml), LDL2 (d = 1.033-1.040 g/ml), and LDL3 (d = 1.040-1.045 g/ml)--to total LDL. A continuous variable, parameter K, was defined to characterize each individual LDL subfraction pattern. Complex segregation analysis of this quantitative trait, under a model which includes a major locus, polygenes, and both common and random environment, was applied to analyze the distribution of the LDL subfraction pattern in these families. The results indicate that the LDL subfraction pattern, described by parameter K, is controlled by a major autosomal, highly penetrant, recessive allele with a population frequency of .19 and an additional multifactorial inheritance component. The penetrance of the more dense LDL subfraction patterns, characterized by values of K < 0, was dependent on age, gender, and, in women, on oral contraceptive use and postmenopausal status. Furthermore, multiple regression analysis revealed that approximately 60% of the variation in the LDL subfraction pattern could be accounted for by alterations in age, gender, relative body weight, smoking habits, hormonal status in women, and lipid and lipoprotein levels. In conclusion, our results indicate that genetic influences as well as environmental exposure, sex, age and hormonal status in women are important in determining the distribution of the LDL subfraction patterns in this population and that these influences may contribute to the explanation of familial clustering of coronary heart disease.
Adult↗
[Influence of body fat topography on glucose homeostasis and serum lipids].
Predominant fat distribution in the upper body segment evaluated by waist to hip circunference ratio (WHR) has been associated with diabetes mellitus and cardiovascular morbidity excess. To investigate metabolic alterations underlying this risk excess, we selected 2 groups of 10 obese women without history of hypertension, menstrual irregularities or oral contraceptives, matched according to age (mean +/- SD): 30.5 +/- 5.3 vs 30.6 +/- 5.8 years and BMI 35.5 +/- 6.5 vs 35.7 +/- 6.7 Kg/m2. Each matched pair had a difference in WHR superior to 0.15 (0.83 +/- 0.04 vs 1.02 +/- 0.05). Insulin and C peptide were determined during an oral glucose tolerance test (75 g). At 30, 60, 90 and 120 minutes differences were significant for glycaemia, insulinaemia and C peptide. Fasting triglycerides were 103 +/- 48 in the lower WHR group vs 164 +/- 84 mg/dl (p less than 0.05); total cholesterol 186.5 +/- 31 vs 215.2 +/- 29.4 mg/dl (p less than 0.05); LDL cholesterol/HDL cholesterol 2.46 +/- 0.89 vs 3.18 +/- 0.96 (p less than 0.05). No significant differences were found in androgenic activity. We conclude that preferential fat distribution in the upper segment is, by itself, an aggravating factor of metabolic alterations associated with obesity, particularly dyslipidaemia and hyperinsulinaemia.
Adipose Tissue↗
[Advances in the research of sperm protein 17].
Sperm protein 17 (Sp17) is a testis-specific protein involved in acrosome reaction in spermatozoa. However, the Sp17 gene has been recently detected in normal non-testis tissues and malignant neoplasias. Therefore Sp17 may be a potential target for immunocontraception and a suitable target for tumor immunotherapy. This paper reviews the advances in the protein characterization, expression and distribution, and biological function of Sp17 and its clinical research.
Animals↗
Effect of an oral contraceptive containing ethinyl estradiol and drospirenone on premenstrual symptomatology and health-related quality of life.
OBJECTIVE: To evaluate the effect of the oral contraceptive Yasmin (drospirenone, 3 mg, and ethinyl estradiol, 30 micrograms) (Berlex Laboratories, Wayne, New Jersey) on premenstrual symptomatology and health-related quality of life (HRQoL). STUDY DESIGN: Participating health care providers received 11,260 self-administered surveys for distribution to women initiating use of Yasmin. Of these, 1,932 (17.2%) baseline surveys and 1,104 follow-up surveys (57.1%) were returned, with 858 (44.4%) of the returns evaluated as suitable for analysis. RESULTS: Premenstrual symptomatology, as measured with the negative affect and water retention domains of the Moos Menstrual Distress Questionnaire (MDQ), significantly improved from baseline in all phases of the menstrual cycle (P = .000). All individual MDQ items improved significantly in the late luteal phase and during menses (P = .000), and the majority (76.9%) improved significantly in the remainder of the cycle (P < .05). Improvements were also observed in general sense of well-being (P < .05), impairment in usual activities due to premenstrual symptomatology (P < .05) and Mental Component Summary scale (P = .000) but not the Physical Component Summary scale of the Short Form-12 generic HRQoL instrument. CONCLUSION: These data support the effectiveness of Yasmin in reducing premenstrual symptomatology and improving HRQoL and general sense of well-being.
Adult↗
Factor V in an industrial population.
Factor-V levels have been measured in a random sample of 626 men and 307 women working in a variety of occupations in North West London. The method is an automated one-stage assay using the same batch of freeze-dried thromboplastin, all results being expressed in terms of the same freeze-dried standard plasma; it has been shown that only one dilution of test plasma is necessary. Factor-V levels are significantly higher when venepuncture is difficult than when it is satisfactory, the mean levels being about 130% and 117% respectively. Factor-V levels are approximately normally distributed; they are similar in men and women and in blacks and whites, and increase significantly with age at the rate of about 0.6% per annum. Factor-V levels are not affected by oral contraceptives or the menopause, and there are no differences according to blood group or secretor status.
Adult↗
A review of the physical and chemical properties of human semen and the formulation of a semen simulant.
A fluid medium was developed to simulate the salient physical and chemical properties of human semen. The composition of the medium was based upon an extensive review of the literature on constituents of human semen. In choosing the ingredients for this medium, the goal was to emphasize properties that influence interactions of human semen with topical contraceptive, prophylactic, or therapeutic products. Among these properties, pH and buffering capacity, osmolarity, ionic strength, and rheological properties play dominant roles in the physico-chemical processes that govern drug release kinetics and delivery vehicle distribution.
Culture Media↗
Safety and tolerability of the new contraceptive sponge Protectaid.
OBJECTIVE: This study was undertaken to assess the efficacy, safety and acceptability of two different-dose regimens of the Protectaid contraceptive sponge. METHODS: The toxic effects of two forms of the new vaginal contraceptive sponge, Protectaid, in the cervical and vaginal tissues were studied. Both types were impregnated with F-5 gel containing different doses of nonoxynol-9 (NX9; 0.5% and 0.125%). The sponge was used by 35 women aged 20-35 years (mean 28.7 years) randomly allocated into two groups (Group A: 0.5% NX9, n = 20; Group B: 0.125% NX9, n = 15). RESULTS: During a 12-month period both regimens demonstrated a 91.4% overall contraceptive efficacy. Colposcopic examinations showed no significant cervical or vaginal lesions in either group, except for two cases at the 2-week and 3-month examinations in Group A women. In the former, inflammatory changes of little clinical significance were seen and the colposcopic appearance of the vagina was non-specific. In this case, the focal lesions were accompanied by dilated capillaries (hyperemia). In the second case, degenerative inflammatory changes, with the inflammatory foci varying in shape and distribution, were observed. Cervical cultures taken 6 months after the start of treatment showed the presence of Mycoplasma hominis and Candida albicans in one and two cases, respectively, in Group A. In Group B, cervical cultures taken at 3 months showed Gardnerella vaginalis and beta-hemolytic streptococci group B in one and two cases, respectively. CONCLUSION: The potent spermicidal and protective properties of this new contraceptive sponge may be of benefit to the sexually active female. Since the sponge was very well accepted by both the study participants and their sexual partners, it can be considered as a valuable barrier method.
Administration, Intravaginal↗
[Determination of intestinal strontium absorption--assessment and validation of routinely manageable test procedures].
Intestinal strontium absorption has been discussed recently as an indirect measure for calcium uptake. Prerequisite for the clinical use of an oral strontium test is the availability of a reliable procedure including controlled strontium supply, sample pretreatment and analysis as well as the assessment of normal values. In the present study, a group of young females (n = 33; 24.0 +/- 2.7 y; BMI 21.5 +/- 1.9) received an oral dose of 2.27 mmol strontium in a standardized breakfast that contained 0.625 mmol calcium. Before and 220 min after the bolus serum strontium concentrations were determined by means of atomic absorption spectrophotometry (coefficient of variation: within day 4.8%, n = 10; day-to-day 9.5%, n = 8). The error of the method was 2.7%. Calculation of the fractional strontium absorption rate considered the respective distribution volume (extracellular fluid; either estimated using body weight or determined by means of bioimpedance analysis [BIA]). Average absorption rates were 13.3 +/- 3.1% and, considering BIA measurement 13.6 +/- 2.6%, respectively. Smoking, exercise and, use of oral contraceptives showed no effects. Our oral strontium test is characterized by excellent reliability, easy handling and low costs and, thus, is suitable for routine use.
Administration, Oral↗
A prospective study of factors affecting age at menopause.
This paper describes a multivariate analysis of a 3-year prospective study of the covariates of age at menopause among women who were randomly sampled from a general population. This approach avoids three problems that may account for the inconsistent results of prior studies: recall bias in retrospectively collected data, failure to control confounding in data analyses, and self-selection in the target populations. At baseline, the 2014 subjects in this study were 46.5-56.5 years old and still menstruating. Median age at last menstruation estimated from a model of the marginal distribution of age at menopause, was 50.7 years. When covariates were considered singly, age at menopause varied with smoking, education and income but not with marital status, parity, location, height, weight or use of either oral contraceptives or menopausal estrogens. Multivariate analyses showed that education and income were confounded with smoking status. The results indicate that many previously identified sources of variation in age at menopause reflect confounding with smoking and self-selection in target populations, rather than real effects.
Adult↗
The pharmacokinetics of 750 microg levonorgestrel following administration of one single dose or two doses at 12- or 24-h interval.
The administration of two tablets of 750 microg levonorgestrel at a 12- to 24-h interval has been shown to be a safe and effective means of emergency contraception, and Norlevo/Vikela (N/V) is a dedicated product for this indication. The aim of this study was to characterize the plasma pharmacokinetics of levonorgestrel following a single N/V tablet administration and following a second administration, 12 or 24 h after the first one in young, healthy, female volunteers under the same conditions as during clinical use. This was an open, observer-blind, randomized study with three parallel groups and three treatments performed in 24 white female volunteers randomized into three groups of eight participants, each receiving one of the following treatments: Group A, one tablet of 750 microg levonorgestrel at time -12 h and one tablet at time 0; Group B, one tablet of 750 microg levonorgestrel at time 0; Group C, one tablet of 750 microg levonorgestrel at time -24 h and one tablet at time 0. All treatments started between Day 2 and Day 6 of the menstrual cycle. Plasma levonorgestrel levels were measured at regular intervals from time 0 up to 36 h with a validated radioimmunoassay. The results of this study show that after either one single or two administrations of a tablet containing 750 microg levonorgestrel, levonorgestrel is rapidly absorbed. The absorption, distribution, and elimination profiles of levonorgestrel following the three different treatments were similar. It also indicates that 12 or 24 h after administration there remains a significant level of plasma levonorgestrel. In conclusion, this study reinforces clinical guidelines recommending that N/V tablets for emergency contraception be administered 12 to 24 h apart because levonorgestrel is present in plasma between the two administrations.
Adult↗
Parental gender preferences and reproductive behaviour: a review of the recent literature.
This paper reviews various theoretical approaches towards an explanation of parental gender preferences and empirical findings from developing as well as from industrialized countries, focusing on the role of gender preferences in reproductive decisions. Although various attempts have been made to shed light on the mechanisms underlying the observed patterns of sex preferences for children, a fully satisfying theoretical explanation is still not at hand. Empirically, a distinct and stable preference for at least one child of each sex can be observed as a common pattern of parental sex preferences across many different social, economic and cultural contexts. Further - and ideally multidisciplinary - research that helps to improve our understanding of this phenomenon is highly desirable.
Contraception Behavior↗
Is multiple sclerosis a sexually transmitted infection?
It is proposed that multiple sclerosis may be transmitted chiefly by sexual contact. Arguments favouring this include: migration studies that suggest a transmissible agent in adolescence; clusters of multiple sclerosis which have occurred in low prevalence areas following entry of young males; the similarity of multiple sclerosis to tropical spastic paraplegia, a known sexually transmitted infection with resemblance to primary progressive multiple sclerosis; an increased rate in drug misusers; a similar age of onset and sex pattern to that found in sexually transmitted disease; increased incidence of multiple sclerosis in those using oral contraceptives; low multiple sclerosis rates in societies with a strict moral code; longitudinal shifts in sex prevalence that show an increase in women after the sexual revolution of the 1960s; and important exceptions to the worldwide distribution corresponding to countries with permissive attitudes to sex. Family, conjugal pair, twin, and adoption studies are compatible with an infectious cause of multiple sclerosis if this is sexually transmitted. It is not proposed that sexual transmission is the only cause but that inherited factors create a susceptibility to a sexually transmitted neurotropic agent. It is hoped this hypothesis might encourage a new direction of neurological research.
Adult↗
Acne. Myths and management issues.
BACKGROUND: Acne is one of the commonest dermatological problems, experienced by approximately 80% of Western adolescents. If left untreated it can be the source of significant physical sequelae and psychological problems. Prevalence studies show that acne is not just a problem of youth but for some, it persists into middle age. OBJECTIVE: To review both the causes of acne and current acne management issues in relation to problems and options for improving outcomes. DISCUSSION: The earlier acne is treated the more likely scarring will be minimised, so a proactive approach is important. The development of oral isotretinoin has offered those with severe, nodulocystic acne the chance of not only disease containment but suppression. However, it is still the only available treatment that targets all four pathological processes involved in acne. The development of antibiotic resistance is becoming a global problem and causing a need to revise our approach to acne.
Acne Vulgaris↗
[Effect of gossypol in combination with misoprostol on termination of early pregnancy in rats and mice].
Treatment of mice with misoprostol alone at doses ranging from 200 to 6400 micrograms.kg-1, qid on day 6-8 or bid on day 9 of gestation, the rate of effective early pregnancy interruption were low and showed no dose effect relation. When giving misoprostol 200-6400 micrograms.kg-1 bid on day 9 of gestation following administration of gossypol 50 mg.kg-1 qid on day 6-8, the rate of abortion increased as the dose of misoprostol increased, and the ED50 of misoprostol was 397.8 micrograms.kg-1. The ED50 of gossypol given orally on day 6-8 of gestation was 69.4 mg.kg-1. However, when gosyypol was given in combination with misoprostol 400, 800 or 1600 micrograms.kg-1 on day 9 bid, the ED50 of gossypol decreased to 63.2, 48.6 or 34.9 mg.kg-1, respectively. The results suggest that combination of gossypol and misoprostol showed synergistic effect on termination of early pregnancy in mice. Misoprostol obviously strengthened the uterine contraction of rats both in early pregnancy and estrus in vitro. The contraceptive intensity of contraction was increased as the dose of misoprostol increased from 10(-9), 10(-8) to 10(-7) mol.L-1, and the estrus group was higher than the early pregnancy group (P < 0.01). Gossypol(10(-5)-10(-6) mol.L-1) showed no effect on the uterine activity in rats, but the sensitivity of the uterus of the early pregnant rats to misoprosrol was found to be significantly increased by treatment with gossypol on day 6-8 of gestation (P < 0.01). Degeneration of the decidual was observed under light microscopy when gossypol 80 mg.kg-1.d-1, or misoprostol 800 micrograms.kg-1.d-1, or gossypol 40 mg.kg-1.d-1 combined with misoprostol 400 micrograms.kg-1.d-1 was given orally to rats on day 6-8 of pregnancy. The degeneration of cells was more remarkable when both drugs were given in combination. The assay of immunoreactivity for PR demonstrated that the distribution and content of PR in uterine decidua had no difference between the control group and the treated groups.
Abortifacient Agents, Nonsteroidal↗
Which teen mothers choose Norplant?
PURPOSE: The objective of this study was to determine if there are sociodemographic differences between adolescent mothers who choose to use Norplant after delivery and those who do not. We hypothesized that those adolescent mothers who are at highest risk for repeat adolescent pregnancy are least likely to select Norplant as a postpartum contraceptive. METHODS: We prospectively compared the prevalence of epidemiologic risk factors for repeat adolescent pregnancy in a group of 187 consecutively delivered 13-18-year-olds who were enrolled in a comprehensive, multidisciplinary, adolescent-oriented maternity program. The study subjects were interviewed at delivery; 100 subsequently had a Norplant inserted (Norplant users). Student's t-tests and chi-square analyses were used to compare Norplant users and refusers. RESULTS: We found no statistically significant differences between Norplant users and refusers with regard to: age, race, Medicaid, or marital or school status. Compared to Norplant refusers, Norplant users were less likely to be primiparous (79% compared to 90%; p = .04) and more likely to have poor school grades (20% compared to 7%; p = .001). Norplant users were more likely to state that they had had trouble remembering to use contraceptives in the past (32% compared to 14%; p = .005). CONCLUSIONS: These data do not support the study hypothesis and are encouraging because they suggest that Norplant may reduce repeat pregnancy among adolescent parents.
Adolescent↗