The rise in multiple births in the United States: who, what, when, where, and why.
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Educational Status↗
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Risk factors for pelvic inflammatory disease. A case control study.
BACKGROUND AND OBJECTIVES: Pelvic inflammatory disease (PID) is associated with major medical and economic consequences for women of reproductive age. Identification of the risk factors associated with PID is crucial to efforts for prevention of these consequences. GOAL: To identify risk factors and markers for symptomatic PID. STUDY DESIGN: A case-control study of 234 women with PID treated at San Francisco General Hospital between October 1986 and August 1989 and 122 controls attending the Women's Clinic at the same institution. The two groups were comparable in sociodemographic, reproductive, sexual, and medical history. RESULTS: Risk factors and markers identified by univariate analysis were < 12 years education, gravidity > 0, parity > 0, spontaneous abortion > 0, lack of a birth control method, > 1 male sexual partner in the previous 30 days, younger than 18 years at age of first sex, history of gonorrhea, sex during the previous menses, douching, exposure to nongonococcal urethritis in the previous 30 days, and history of crack cocaine use. With multivariate analysis to control for confounders the risks still identified were parity > 0, (odds ratio [OR] 4.44; 95% confidence interval [CI] 2.34 to 8.42), > 1 sexual partner in the previous 30 days (OR 11.08; 95% CI 4.31 to 28.5), sex during the previous menses (OR 5.22; 95% CI 1.88 to 14.48), and a lack of contraception (OR 7.6; 95% CI 4.10 to 14.09). CONCLUSIONS: Findings indicated that certain reproductive behaviors could be targeted for public health attention and risk reduction interventions to reduce the incidence of PID. These include limiting numbers of sexual partners and encouraging the use of barrier methods of contraception for sexually transmitted disease prevention. Another finding was that it is probably best to avoid sexual intercourse during the menses. The question of douching as a risk factor for PID could not be answered by this study.
Adolescent↗
Undernutrition and food rehabilitation effects on the locus coeruleus in the rat.
Perinatal nutrition plays a fundamental role on the morphological organization and function of a number of brain stem structures. Because little is known of the effects of perinatal undernutrition upon sexually dimorphic structures underlying reproductive behavior, the locus coeruleus morphology of 60-day-old male and female Wistar rats was analyzed. Perinatal food deprivation until weaning significantly decreased the volume and neuronal number of locus coerulus in male and female rats, while nutritional rehabilitation ameliorated these alterations in males but not in females. Data suggest that perinatal undernutrition interferes with the neuroendocrine mechanisms underlying the establishment of sex differences of the locus coeruleus.
Animals↗
Biosynthesis and emission of terpenoid volatiles from Arabidopsis flowers.
Arabidopsis is believed to be mostly self-pollinated, although several lines of genetic and morphological evidence indicate that insect-mediated outcrossing occurs with at least a low frequency in wild populations. Here, we show that Arabidopsis flowers emit both monoterpenes and sesquiterpenes, potential olfactory cues for pollinating insects. Of the 32 terpene synthase genes in the Arabidopsis genome, 20 were found to be expressed in flowers, 6 of these exclusively or almost exclusively so. Two terpene synthase genes expressed exclusively in the flowers and one terpene synthase gene expressed almost exclusively in the flowers were characterized and found to encode proteins that catalyze the formation of major floral volatiles. A beta-glucuronidase fusion construct with a promoter of one of these genes demonstrated that gene expression was restricted to the sepals, stigmas, anther filaments, and receptacles, reaching a peak when the stigma was receptive to cross pollen. The observation that Arabidopsis flowers synthesize and emit volatiles raises intriguing questions about the reproductive behavior of Arabidopsis in the wild and allows detailed investigations of floral volatile biosynthesis and its regulation to be performed with this model plant system.
Alkyl and Aryl Transferases↗
Effects of developmental environment on signal-preference coupling in a Hawaiian cricket.
Previous work has suggested that developmental temperature influences expression of the adult male calling song of the cricket, a sexually selected mate recognition signal. The role of developmental temperature in shaping female preference functions, and thus its influence on signal-preference coupling has not been investigated. In this study, the effects of developmental temperature are examined in both males and females of the Hawaiian cricket, Laupala cerasina, to determine the degree of signal-preference matching between male song and female preference due to developmental environment. We found that rearing females in different temperature environments affected adult female acoustic preference functions in the same direction as male calling song, thereby influencing variation in adult reproductive behavior in such a way that male and female components remain coordinated. However, we further demonstrate that for male song, the effect of the rearing environment is not permanent but appears only to exert influence for a period of days. This mid-term temperature effect is distinct from the effect of short-term ambient temperature, which influences song in a matter of minutes and has been well documented. Signal-preference coordination, and sexual selection pressures due to mismatching within natural populations, likely will be influenced by nymphal developmental environments of males and females, as well as by adult singing and preference environments.
Animal Communication↗
Fos expression in the rat brain following vaginal-cervical stimulation by mating and manual probing.
Vaginal-cervical stimulation (VCS), provided by mating or manual probing, induces many reproductive behavioral and endocrine changes in female rats. These changes include an increase in lordosis duration, heat termination and pseudopregnancy. Electrophysiological and [14C]2-deoxy-D-glucose studies collectively show that neurons in the medial preoptic area, ventromedial hypothalamus and midbrain central gray respond to manual VCS. In the present study we immunocytochemically labeled brain sections for Fos, the protein product of the immediate early gene c-fos, to detect VCS-responsive neurons in hormone-primed animals receiving VCS by mating or manual probing. In Experiment 1, females receiving mounts and intromissions were compared to: 1) vaginally-masked females receiving mounts but no VCS, 2) females exposed to an intact anesthetized male or 3) females not exposed to males or the testing arena. Those animals receiving VCS showed a dramatic increase in the number of Fos-immunoreactive cells in the medial preoptic area, posterodorsal portion of the medial amygdala and bed nucleus of the stria terminalis, as well as the dorsomedial hypothalamus, ventromedial hypothalamus and midbrain central gray. These effects of VCS were confirmed in Experiment 2 in animals receiving manual vaginal-cervical probing. These findings extend previous electrophysiological and [14C]2-deoxy-D-glucose studies by providing evidence that additional brain areas respond to VCS by mating, as well as manual probing.
Animals↗
Gynaecological and sexuality profile of new patients attending a family planning clinic.
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Adolescent↗
Ethinyl oestradiol and D-norgestrel is an effective emergency postcoital contraceptive: a report of its use in 1,200 patients in a family planning clinic.
We describe a prospective study of 1,200 patients using the Yuzpe regimen of hormonal postcoital contraception. There was an 85% follow-up rate, and of the 1,015 patients followed there were 13 pregnancies, giving a pregnancy rate of 1.3%. The number of expected pregnancies at mid-cycle was reduced by 83%; 12 of the 13 pregnancies went on to abortion. The patients were young: 86% were under 25, and 10% were under 15. The most frequent reason for presentation was that no contraception had been used (57%). All patients received an antiemetic; 57% experienced no side-effects, 28% had some nausea and 9.6% some vomiting. It is concluded that this is a safe form of emergency contraception, which is an effective way of reducing the number of unwanted pregnancies, especially in the very young.
Adolescent↗
High prevalence of chlamydia and Pap-smear abnormalities in pregnant adolescents warrants routine screening.
A prospective cohort of pregnant adolescent patients who planned to deliver at 1 of 3 Perth metropolitan hospitals was studied; 1 subgroup of this cohort was offered universal screening for cervical chlamydial infection and Pap-smear abnormalities (screened), and the remainder of the cohort were offered screening at the discretion of the attending medical staff (control). High prevalences of both chlamydial infection (27%) and Pap-smear abnormalities (38%) were detected in the screened cohort. The majority of Pap-smear abnormalities were inflammatory atypia, but high-grade Bethesda lesions were also diagnosed. In the control group, the prevalence of positive swabs and abnormal Pap-smear reports in those tested was also high (22% and 35% respectively), but significantly fewer patients were tested (18% and 33% respectively in the control group, compared to 92% and 94% in the screened group; both p<0.001). Screening and treatment of chlamydia was associated with a significant decrease in the incidence of newborn febrile morbidity (10% versus 25%; p=0.02). In view of the high prevalence of positive results, it is cost-effective to offer universal screening in this setting. Failure to introduce a specific screening policy can result in a significant number of patients being denied the advantages of diagnosis and treatment.
Adolescent↗
Alcohol preference and hepatic alcohol dehydrogenase activity in adult Long-Evans rats is affected by intrauterine sibling contiguity.
Alcohol preference and hepatic alcohol dehydrogenase activity in adult rats are known to be sexually dimorphic. Intrauterine sibling contiguity (the intrauterine position of a fetus relative to adjacent siblings of the same or opposite sex) alters selected reproductive, behavioral and enzymatic sexual dimorphisms via intersibling sex hormone transfer. We postulated that sibling contiguity would affect alcohol preference and hepatic alcohol metabolism in adult rats. The results of our study demonstrate that adult mMm male Long-Evans rats (genetic male rat developing in utero between two male siblings) had significantly lower ethanol preference, attained higher blood alcohol levels after standard ethanol "challenge" doses and had significantly lower hepatic alcohol dehydrogenase activity than either male siblings developing in utero between two females (fMf) or genetic females developing between two males or between two females (mFm or fFf). Hepatic cytosolic aldehyde dehydrogenase activity was higher in adult female than male rats regardless of nearest neighbor siblings. It is suggested that the differences in ethanol preference and hepatic alcohol dehydrogenase activity between the adult mMm and fMf male rats is due to differences in prenatal hormonal environment which can modulate sexual dimorphisms in alcohol intake and metabolism in the adult.
Alcohol Dehydrogenase↗
Health problems and sexual activity of selected inner city, middle school students.
Physical examinations were performed and health and sexual histories were taken on 496 12-14-year-old, inner city, middle school students participating in extracurricular activities. Health problems were identified in 9.5% of students. Twenty-one percent of a subgroup of 276 students reported sexual activity; males were three times as likely as females to report intercourse. More than one-half of a smaller subgroup named their parents as their primary source of information on sex. The value of the screening exam is discussed, and suggestions are offered on the content of preventive health and sex education curricula for this age group.
Adolescent↗
Testosterone concentration in the male chick brain: an autoradiographic survey.
Differential uptake of [(3)H]testosterone in male chick brain was found in periventricular areas of preoptic-hypothalamic continuum. Concentration of silver grains for all decapitation periods was especially high in the medial preoptic area, particularly the nucleus praeopticus paraventricularis magnocellularis. Distribution of testosterone-sensitive cells is in agreement with studies showing neuroanatomical control of reproductive behavior by the avian forebrain.
Animals↗
Ingestion of Salmonella enterica serotype Poona by a free-living mematode, Caenorhabditis elegans, and protection against inactivation by produce sanitizers.
Free-living nematodes are known to ingest food-borne pathogens and may serve as vectors to contaminate preharvest fruits and vegetables. Caenorhabditis elegans was selected as a model to study the effectiveness of sanitizers in killing Salmonella enterica serotype Poona ingested by free-living nematodes. Aqueous suspensions of adult worms that had fed on S. enterica serotype Poona were treated with produce sanitizers. Treatment with 20 microg of free chlorine/ml significantly (alpha = 0.05) reduced the population of S. enterica serotype Poona compared to results for treating worms with water (control). However, there was no significant difference in the number of S. enterica serotype Poona cells surviving treatments with 20 to 500 microg of chlorine/ml, suggesting that reductions caused by treatment with 20 microg of chlorine/ml resulted from inactivation of S. enterica serotype Poona on the surface of C. elegans but not cells protected by the worm cuticle after ingestion. Treatment with Sanova (850 or 1,200 microg/ml), an acidified sodium chlorite sanitizer, caused reductions of 5.74 and 6.34 log(10) CFU/worm, respectively, compared to reductions from treating worms with water. Treatment with 20 or 40 microg of Tsunami 200/ml, a peroxyacetic acid-based sanitizer, resulted in reductions of 4.83 and 5.34 log(10) CFU/worm, respectively, compared to numbers detected on or in worms treated with water. Among the organic acids evaluated at a concentration of 2%, acetic acid was the least effective in killing S. enterica serotype Poona and lactic acid was the most effective. Treatment with up to 500 microg of chlorine/ml, 1% hydrogen peroxide, 2,550 microg of Sanova/ml, 40 microg of Tsunami 200/ml, or 2% acetic, citric, or lactic acid had no effect on the viability or reproductive behavior of C. elegans. Treatments were also applied to cantaloupe rind and lettuce inoculated with S. enterica serotype Poona or C. elegans that had ingested S. enterica serotype Poona. Protection of ingested S. enterica serotype Poona against sanitizers applied to cantaloupe was not evident; however, ingestion afforded protection of the pathogen on lettuce. These results indicate that S. enterica serotype Poona ingested by C. elegans may be protected against treatment with chlorine and other sanitizers, although the basis for this protection remains unclear.
Animals↗
Melting the Iron Curtain: opportunities for public health collaboration through international joint ventures.
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Female↗
Abnormalities in the oestrous cycle in the mare.
The situations and conditions that can disrupt the mares normal oestrous cycle are described. Season of the year is a major influence; maximum reproductive efficiency does not totally coincide with the artificially defined "breeding season". Other abnormalities are associated with spontaneously persistent luteal function, psychological influences over behavioural activity, the presence of endometritis, multiple ovulation, reproductive behavior after pregnancy failure and granulosa cell tumours.
Animals↗
Population and women's reproductive health: an international perspective.
This paper gives a brief overview of current world population or demographic issues, followed by a discussion of the ICPD proceedings and various notable aspects of the ICPD Programme of Action. It then focuses on six of the most pressing reproductive health concerns facing women today: gender inequalities, access to contraceptive services, sexually transmitted diseases (including HIV), maternal mortality, unsafe abortion, and adolescent pregnancy. Because the ICPD Programme of Action is intended to have far-reaching consequences for each of these issues, it is taken as a focal point of analysis.
Abortion, Legal↗
Teen pregnancy prevention: do any programs work?
This paper begins with a review of the problem of teen pregnancy in the United States. Domestic trends are compared with those of other developed countries. Antecedents of the problem are discussed. New developments in addressing the problem are then described, including the following: (a) a renewed emphasis on abstinence on the one hand; (b) a move toward a more positive view of teen sexuality on the other; (c) the development of new prevention initiatives such as STD/HIV/AIDS prevention programs, community-wide teen pregnancy prevention collaboratives, broad-based youth development programs, and state and local government initiatives; and (d) the lauching of the National Campaign to Prevent Teen Pregnancy. An analysis of the different ways in which the problem can be framed and the implications for solutions of the problem follow. Examples of promising teen pregnancy and STD/HIV/AIDS prevention programs are provided. The paper ends with a recommendation for an eclectic approach to framing the problem and possible solutions.
Adolescent↗
Identification of neural circuits involved in female genital responses in the rat: a dual virus and anterograde tracing study.
The spinal and peripheral innervation of the clitoris and vagina are fairly well understood. However, little is known regarding supraspinal control of these pelvic structures. The multisynaptic tracer pseudorabies virus (PRV) was used to map the brain neurons that innervate the clitoris and vagina. To delineate forebrain input on PRV-labeled cells, the anterograde tracer biotinylated dextran amine was injected in the medial preoptic area (MPO), ventromedial nucleus of the hypothalamus (VMN), or the midbrain periaqueductal gray (PAG) 10 days before viral injections. These brain regions have been intimately linked to various aspects of female reproductive behavior. After viral injections (4 days) in the vagina and clitoris, PRV-labeled cells were observed in the paraventricular nucleus (PVN), Barrington's nucleus, the A5 region, and the nucleus paragigantocellularis (nPGi). At 5 days postviral administration, additional PRV-labeled cells were observed within the preoptic region, VMN, PAG, and lateral hypothalamus. Anterograde labeling from the MPO terminated among PRV-positive cells primarily within the dorsal PVN of the hypothalamus, ventrolateral VMN (VMNvl), caudal PAG, and nPGi. Anterograde labeling from the VMN terminated among PRV-positive cells in the MPO and lateral/ventrolateral PAG. Anterograde labeling from the PAG terminated among PRV-positive cells in the PVN, ventral hypothalamus, and nPGi. Transynaptically labeled cells in the lateral hypothalamus, Barrington's nucleus, and ventromedial medulla received innervation from all three sources. These studies, together, identify several central nervous system (CNS) sites participating in the neural control of female sexual responses. They also provide the first data demonstrating a link between the MPO, VMNvl, and PAG and CNS regions innervating the clitoris and vagina, providing support that these areas play a major role in female genital responses.
Afferent Pathways↗