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PubMed1992

Fetal heart rate response to acoustic stimulation in relation to fetal development and hearing impairment.

In twelve healthy pregnant women the fetal heart rate response to sound stimulation was tested every second week between the 22nd and the 34th week of the pregnancy. Habituation to the acoustic stimuli used was also investigated at the last examination. A high risk material for hearing impairment comprised 31 pregnant women. The stimuli were presented by a vibrator placed on the maternal abdomen over the fetal head. As stimuli pure tones were used in the form of pulses of one second at a frequency of 3000 Hz and with an onset and a decay time chosen not to cause audible clicks to a normal ear. The intensity of the tone pulse was set at a level calculated to correspond at the position of the fetal head to 110 dB sound pressure level in free field. Roughly 50% of the fetuses tested started to react with an increased heart rate in the 24th week of the development. Four weeks later all tested subjects responded to the test stimuli. Habituation of the motor 'startle' response was shown but the fetus heart rate change was consistent over 20 consecutive stimulations one min in between each. In 31 high risk subjects the responses from three fetuses must be considered as pathologic. These three children exhibited impaired auditory tests after birth and severe hearing impairment at the age of three years. All the others disclosed normal hearing at birth as well as at three years of age. Repeated significant increases in fetal heart rate following acoustic stimulation may appear as an indication of normal function of the hearing organ.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustic Stimulation↗
PubMed1978

Fertility and family planning in rural northern Thailand.

From the mid-1960s to the mid-1970s, when fertility was declining in Thailand as a whole, especially rapid declines occurred in Northern Thailand, but they did not occur uniformly in all the region's provinces. The Northern Thailand Fertility Study, initiated in 1975 to study the reported fertility changes, gathered data in two provinces: Chiang Mai, where fertility decline has been quite rapid, and Chiang Rai, which experienced relatively little decline until 1974. This preliminary report discusses fertility levels and trends in the two provinces, fertility experience and expectations of respondents, attitudes toward and knowledge of family planning, and contraceptive practice. The results suggest that most of the difference in fertility decline is related to the different level of family planning program activity in the two provinces.

Abortion, Spontaneous↗
PubMed1979

Postnatal effects of prenatal sound stimulation in the guinea pig.

Pregnant guinea pigs were stimulated with a natural sound alien to their species. Postnatally the response of their young to this sound was compared with that of unstimulated controls. All young were tested with a series of the alien sounds followed by series of guinea pig calls. Heart rate changes showed that prenatally stimulated young responded less to the alien sounds than did controls, whereas both groups responded equally to guinea pig calls. Response of controls diminished during daily test sessions and over the five test days and comparison with an older control group showed that this was due to repetition of the stimulus. It is suggested that the response of prenatally stimulated animals had waned before birth.

Animal Communication↗
PubMed1991

Can combined oral contraceptives be made more effective by means of a nursing care model?

This manuscript is a theoretical attempt to show how the Neuman Systems Model can be practically used in combined oral contraceptive counselling by Swedish midwives. Counselling regarding combined oral contraceptives is not solely of a medical nature. There are many dimensions of care, namely sociological, developmental and philosophical. In 1980, the midwife in Sweden was responsible for between 70-80% of counselling in contraceptive methods. To facilitate the contraceptive counselling by the midwives, the Neuman Systems Model can be used as a theoretical aid. In the present report, the midwife's oral contraceptive counselling is described at an individual level with primary prevention. It is concluded that, from a theoretical standpoint, it is not possible to predict how the Neuman Systems Model, as a theoretical aid for the midwife, can increase the effectiveness of the birth control pill in preventing pregnancy. Research about the use of the nursing care model in oral contraceptive counselling should be carried out.

Adult↗
PubMed1976

Beta-glucuronidase isozyme patterns of experimental hepatomas of rats.

Beta-Glucuronidase isozymes in rat tissues were separated by electrophoresis on cellulose acetate membranes. Using this method, beta-glucuronidase isozyme patterns were studied in normal rat liver and experimental hepatomas with different growth rates. Changes of isozyme patterns during postnatal development were also studied in rat liver. Normal rat liver contained six types of beta-glucuronidase, numbered I to VI in order to decreasing mobility to the cathode. Type II beta-glucuronidase stained most intensely and was detected in all the cells examined. The isozyme patterns of Morris hepatomas, which are slowly growing and not highly deviated, resembled that of normal rat liver but lacked definite Type III beta-glucuronidase. Yoshida ascites hepatomas, which are rapidly growing and highly deviated, contained only Type II, but some had Types II, V, and VI beta-glucuronidase. Embryonal liver just before birth contained only Type II, but with increase in activity during development after birth, minor bands of Type I and Types III to VI beta-glucuronidase appeared successively to complete the adult pattern.

Animals↗
PubMed1976

Cardiovascular effects of electrical stimulation of the forebrain in the fetal lamb.

Modified stereotaxic techniques were applied to fetal lambs during the latter third of gestation. Electrical stimulation in the region of the hypothalamus in 10 acute experiments was associated with three patterns of arterial blood pressure and heart rate changes: a pressor-tachycardia response; a pure tachycardia response (abolished by propranolol); and a pure bradycardia response (abolished by atropine). The pressor-tachycardia response was examined in detail in 13 chronic preparations (115-135 days of gestation at operation). The systolic arterial blood pressure increase was never greater than 35 mm Hg and was probably blunted by the large noninnervated placental circulation. This pressure increase was abolished by phentolamine and was thus mediated by stimulation of alpha-adrenergic receptors. The initial tachycardia was prevented by propranolol and was due to beta-adrenergic stimulation. The tachycardia was followed in a few seconds by a bradycardia, abolished by atropine and possibly a vagal baroreflex. The pressor-tachycardia response was accentuated in two lambs who were delivered spontaneously and were studied after birth. These studies indicate that a suprabulbar neural framework exists in the fetal lamb for influencing the cardiovascular system from as early as 90 days of gestation.

Adrenergic beta-Antagonists↗
PubMed1979

Survey of abortion providers in Seoul, Korea.

A survey of abortion providers in Seoul in late 1977 reveals a threefold increase in the rate of abortion and a greater than threefold rise in the ratio of abortions to live births since 1970. The survey findings also show that the overwhelming proportion of these abortions are performed in private clinics, by obstetrician-gynecologists, during the first trimester. The Seoul figures, which are similar to those of Romania and are higher than those of Japan in the early 1960s, indicate that abortion has contributed substantially to Korea's reduced fertility.

Abortion, Legal↗
PubMed1991

On the significance of remodeling space and activation rate changes in bone remodeling.

This paper quantifies the relative contributions of the remodeling space and the accumulation of Haversian canals to bone porosity at various ages. It also examines the importance of variations in the rate of bone remodeling that occur during growth and aging, and as a result of trauma and disease. The dependence of the remodeling space (cavities due to resorbing, reversing, and refilling BMUs) and the Haversian canal components of porosity on the Basic Multicellular Unit (BMU) activation frequency are mathematically formulated. A graph is developed using data for the cortex of the human rib which shows the extent to which porosity is primarily due to the remodeling space in children, and to accumulated Haversian canals in adults. It is shown that the diminution of activation frequency between birth and age 35 contributes to the concurrent increase in bone volume fraction, and the increase in activation frequency after age 35 contributes to the subsequent decline of bone volume fraction. An equation is derived for determining the time rate of change of activation frequency using two fluorochrome labels.

Aging↗
PubMed1992

Combined effects of body size, parity, and menstrual events on breast cancer incidence in seven countries.

A biologically motivated breast cancer incidence rate function was fit to data from a published case-control study conducted in countries whose incidence is high (Wales and the United States), moderate (Brazil, Greece, and Yugoslavia), and low (Japan and Taiwan). The data include personal characteristics of 3,925 breast cancer cases and 11,327 controls interviewed in selected hospitals in 1964-1968. Parameters in the function specify the dependence of age-specific breast cancer incidence rates on age at menarche, age at menopause, occurrence and timing of full-term pregnancies, and body mass. Parameters were estimated separately for high-, moderate-, and low-risk countries. Examination of residuals provided little evidence of inadequacy of the fitted function in describing combined effects of the characteristics studied. The following patterns were seen in all three risk groups: 1) Incidence rates jump to a higher level after first childbirth, but then increase with age more slowly thereafter. 2) Rates increase with age more slowly after menopause than before. 3) Rates change quadratically with body mass index among all women, although the main trend varies: Rates decrease with body mass among premenopausal women in high-risk countries, but increase with body mass in all other groups of women. Similarities of parameter estimates across countries suggest that reproductive events and body fat exert similar effects on all women, regardless of breast cancer rates in their country of residence.

Adult↗
PubMed1991

Fertility rates in 238 HIV-1-seropositive women in Zaire followed for 3 years post-partum.

Birth-control use and fertility rates were prospectively determined in 238 HIV-1-seropositive and 315 HIV-1-seronegative women in Kinshasa, Zaire, during the 36-month period following the delivery of their last live-born child. No women delivered children during the first follow-up year. Birth-control utilization rates (percentage use during total observation time) and fertility rates (annual number of live births per 1000 women of child-bearing age) in the second year of follow-up were 19% (107.4 per 1000) for HIV-1-seropositive women and 16% (144.7 per 1000) for HIV-1-seronegative women. In the third year of follow-up these rates were 26 (271.0 per 1000) and 16% (38.6 per 1000) for HIV-1-seropositive and HIV-1-seronegative women, respectively (P less than 0.05 for the difference in birth-control utilization and fertility rates between seropositive and seronegative women in the third year of follow-up). Seven (2.9%) of the 238 HIV-1-seropositive women initially included in the study brought their sex partners in for HIV-1 testing; three (43%) of these men were found to be HIV-1-seropositive. New HIV-1 infection did not have a dramatic effect on the fertility of seropositive women. The nearly uniform unwillingness of HIV-1-seropositive women to inform husbands or sexual partners of their HIV-1 serostatus accounted in large part for the disappointingly high fertility rates in seropositive women who had been provided with a comprehensive program of HIV counseling and birth control. Counseling services for seropositive women of child-bearing age which do not also include these women's sexual partners are unlikely to have an important impact on their high fertility rates.

AIDS-Related Complex↗
PubMed1975

Family planning services in the United States.

In recent years the United States has made considerable progress in providing family planning services for those in need. This does not mean, however, that the problems posed by unwanted pregnancies and unwanted births have been completely overcome. Estimates of the number of low-income women needing and receiving family planning services indicate that roughly 3.6 million women at risk of an unwanted pregnancy were receiving family planning services in 1973. This represented almost two-thirds of those in need at the time. Many programs are also seeking to meet the teenage need demonstrated by very high rates of out-of-wedlock births, premarital conceptions, obstetric problems, and legal abortion demands of women 15 to 19 years of age. As of 1973, it appeared that between 1.3 and 2.2 million never-married teenagers were in need of organized family planning services, and that of these, services were being received by between 25 and 42 per cent.

Abortion, Legal↗
PubMed1975

The containment of world population growth.

The world has reached the present position of unprecedentedly rapid population growth not by achieving uniquely high fertility but by bringing about extraordinarily low mortality. The high growth rate and the built-in momentum of the age structure are obstacles to achievement of an acceptable standard of living for most of the world's population. Although government population programs have the potential to curb this growth rate, this potential has not been realized, and such programs are too often perceived both by their administrators and the population concerned as an end in themselves rather than a means toward a better standard of living. It is in this latter perspective, and in the context of the total development process, that population programs should be implemented.

Adult↗
PubMed1978

What will 1984 be like? Socioeconomic implications of recent twists in age structure.

Since 1940, under conditions of restricted immigration and high and sustained growth in aggregate demand, shifts in the relative number of younger versus older adults have had a pervasive impact on American life. Before 1960, younger males were in increasingly short supply and their relative economic position substantially improved; after 1960, the opposite was true. Since the early sixties, as the relative condition of young adults has deteriorated, marriage has been increasingly deferred and fertility reduced. The labor force participation of young women has risen at above average rates, and that of older women has risen at below average rates. Changes in the age structure of the working age population have also contributed to a combination of rising unemployment and accelerating inflation. Cohort divorce rates, suicide among young males, crime rates, and political alienation have worsened. The rise in college enrollment rates has been interrupted, and SAT scores have declined. In contrast, in the period 1940-1960, changes in these various magnitudes were typically of a more favorable sort. The United States is now at the start of a new period of growing scarcity of young adults as a result of the birth rate decline that set in after 1960. This implies that the 1980s will see a turnaround or amelioration in a wide variety of these social, political, and economic conditions, some of which have been taken as symptomatic of a hardening social malaise.

Adult↗