Birth and death rates are two major components of population growth. A time series analysis of birth and death rates in Tripura state was conducted during 1971-89 using rates taken from the Basic Statistics of Northeastern Region, Northeastern Council Secretariat, Shillong. The analysis found that both birth and death rates in the state were changing over time in both urban and rural areas. The birth rate, however, is declining more slowly than the death rate. Birth rates in the state over the period for the overall population, rural areas, and urban centers are more than twice as large as the death rates in any given year, one of the main reasons for population growth in Tripura state. A high rate of immigration from the neighboring country is another likely reason for rapid population growth in the state.

5068 maternity histories were recorded among women aged 15-89 years in a rural area of Senegal. The quality of the estimates of fertility, child mortality, and perinatal mortality was analyzed for consistency. There was no evidence of any major underreporting of births, deaths, or still births according to age, even among the oldest women. Estimates were compared with comparable values derived from a longitudinal demographic surveillance system (DSS) in the same area. The age patterns of cumulated fertility and mortality derived from the maternity histories were consistent with those of the DSS. Differences in the levels of fertility and mortality with respect to the longitudinal records could be explained by small differences within the selected villages, by selection biases, and by recent trends in demographic parameters. Values of perinatal mortality were also equivalent to those recorded by the DSS. Women did not seem to forget their births to an extent large enough to produce strong biases, even at older ages. However, an analysis of differences by field workers revealed that some 2% of the births and 4% of the deaths may have been omitted, which gives an idea of the potential accuracy of maternity histories for the estimation of fertility and mortality levels.

The following conditions must be met in order for sex preference to affect fertility: 1) fertility decline, 2) use of contraception to control births, and 3) a small family size. Fertility in 1990 was 2.25 children, and contraceptive use was 73.24% of married women of reproductive age in 1987. The Chinese one-child policy made it difficult to satisfy sex preference goals. A number of methods were described for measuring the extent of sex preference. Preference may be contained in a survey question about preference regardless of birth control policy. Personal pregnancy and contraceptive use histories provide another means of evaluating the presence of sex preference. Chinese surveys in 1985 and 1987 showed that women preferred boys, regardless of whether each woman already had a boy and a girl. The general fertility rate by sex is another measure for assessing demand. Simulations, which hypothetically determined the extent of sex preference, showed that only 90 families out of every 1000 families could have only a girl, when the general fertility rate was under 2.287. Analysis of data from a survey of suburban Xiangyang City, Shaanxi Province in 1987 revealed that elderly parents benefitted more from boy children. A simulation of the demand for taking care of parents in old age showed 2.3 children were needed to satisfy the demand for boys in the 1970s; 71 families out of a 100 would have only girls (202 girls per 1000 mothers). Choice of methods was found in a simulation to be highly correlated with the number and sex of surviving children. A greater proportion of women, who had one or two girls, did not use contraception compared to women with boys. The probability of abandoning contraception within 4 years by a woman with a girl child was 90% in contrast to 85% for a woman with two boys within 6 years. Those women with a boy and a girl had stable contraceptive patterns. The proportion with an additional pregnancy was smaller among those with both a boy and a girl. Rejection of contraception, use for a short time, or an additional pregnancy were related to having one child or girl children.

With the sudden decline of fertility it was particularly interesting to examine the situation in Kerala, regarding parental sex preference in formulating family planning policies for the rest of India with high fertility and son preference. The 1980 Kerala Fertility Survey included nearly 3000 households with about 2700 ever married women in reproductive age. Maternity history and fertility regulation data were collected. Data from 2500 currently married women were used, cross-classified by the number of male and female living children and contraceptive use status. A multiplicative model was used to study various interaction effects and to construct standardized rates of contraceptive use. Measures adjusted for both male and female composition and differential use of contraceptives among male-female combinations were obtained by the model to avoid arbitrariness in choosing rates and to preclude objections raised in previous research on Arnold\'s index. The model was generalized to facilitate simultaneous effects of the number of male and female children and family size on contraceptive use. Initial analysis showed that the effect of sex preference on contraceptive acceptance was rather negligible. However, there was a significant male-female interaction effect on contraceptive use. Contraception was high when the family size was large, with children of the same sex. With the effect of family size removed, the contraceptive use rate seemed to be in the inverse direction of the number of male or female children. This was possibly the result of two factors: 1) high contraception rate with large families of the same sex, and 2) low use of contraception among large families with a high number of children of both sexes. The Kerala situation partly supports McClelland\'s theory that couples already having proportionally more daughters may terminate fertility earlier. In Kerala such termination also occurs when couples have proportionally more sons, and family size also plays an important role in fertility cessation.

\"In order to make up for the incompleteness of data in the last 40 years, this paper will try to make a preliminary study of the age-specific mortality rate and average life expectancy and its changing trends [for] the Chinese population over the last 40 years, based on the relevant data on mortality from sample surveys on fertility and birth control among Chinese women.\"

A multicenter comparative clinical study of the Stainless steel ring VCu 200 and TCu 200c in a cohort of 6236 subjects was conducted in 23 centers in 13 provinces and municipalities in China. The followup rate at the end of 5 years was 96.0%. Woman-years of use were 6802.8 for the steel ring, 8373.3 for VCu 200, and 8712.3 for TCu 220c. 5-year gross cumulative continuation rates/100 women were 55.8, 68.6, and 72.4 respectively. VCu 200 and TCu 220c had significantly lower pregnancy rates (7.32% and 7.24%, respectively) while that of the steel ring was 20.21%. There were significant differences in the 5-year expulsion rates among steel ring (19.0%), VCu 200 (9.7%), and TCu 220c (5.6%). The removal for bleeding and/or pain was the lowest in the steel ring group and there were no significant differences between the other 2 models. The rates of pregnancy, expulsion, and discontinuation due to personal reasons in the rural areas were higher than in urban areas. The expulsion risk of TCu 220c was only affected by insertion during lactation and the factors responsible for expulsion with the VCu 220c were age, gravida, and previous IUD use. In addition to these 3 factors, expulsion of the steel ring was influenced by the length of the uterine cavity. (author\'s modified)

A probability model is presented describing the variation in open birth intervals regardless of parity of women having specific marital duration. Open birth intervals is the period between the date of last birth and the date of the survey. This model may be applied to analyze data for women of both short and long marital duration. Open birth intervals for any marriage cohort may be models. For illustrative purposes, the model is applied to open birth interval data collected in the Demographic Survey of Varanasi in 1969-70. Women with 10 years marital duration are considered for the study, excluding those who have not given birth over a 10-year period.

A blocking device made of silicon rubber was adopted for tubal blocking by transperitoneal manipulation on 30 domestic rabbits with an observation period of 3-24 months. 100% success with sterilization was obtained. Removal of the plug transperitoneally was carried out on 16 rabbits with successful sterilization and 15 of the 16 were pregnant within 2 months. Successful rates of pregnancy amounted to 93.75%. Histological study revealed that the continuity of the tubal lumina was maintained by the use of this procedure with very little damage to the tissues, and that whatever damaged tissue there was, it would be completely recovered after removal of the plug. Thus, the reversibility of the procedure is clear. This blocking procedure with silastic rubber plugs was utilized among 232 women in clinical trials beginning in June, 1984. The longest observation period was 42 months, the shortest 12. 1 patient did not have a successful procedure, thus bringing the sterilization rate down to 99.57%. In May, 1987, plugs were removed from 8 women who had been successfully sterilized for 1 year; of these 8 women, 7 have achieved an intrauterine pregnancy within 1 year. (author\'s modified)

Research on the Bagatha tribe and the Malas and Madigas in India has been done for economic and social planning purposes in regard to family planning. Bagatha are mostly agricultural people where the nuclear family is prevalent and polygamy is popular as well as cousin marriage. The Madigas and Males (Harijans) are lower caste with the 1st being leather workers and the latter being agricultural helpers. The data was collected by direct interview of 202 tribesmen and 202 caste households with women from 15-49 years of age. The data collected on fertility include live births, child survival rate, fetal wastage, husband and wives education, income, and occupations. On mortality, the number of deaths, age at marriage, number of and intervals of pregnancies. As expected, educated and employed families show healthier and higher levels of fertility especially if the wife is educated. The wife shows more of the responsibility for family planning. The age at marriage and the number of pregnancies appears to have little effect on mortality. In the caste group the education level of the husband has little effect on fertility and again the wife has the primary responsibility in using family planning techniques.

The Korean population experienced a drastic demographic transition in this century. The family planning program has dramatically decreased the fertility rate. The total fertility rate, which was 6 in 1960, decreased to 4.3 in 1970, 2.8 in 1980, 2.1 in 1985, and 1.7 in 1988. The government now predicts a stationary population of 52 million in 2020. Population policy must recognize the relationship between population growth and socioeconomic factors. Urban population has increased very rapidly due to socio-political change and industrialization. The urban population comprised 1/5 of the total population in 1960, forms 2/3 of the present population, and will form 4/5 of the population in 2020. Modernization brings the problems associated with education, employment, marriage, housing, family, and ultimately the aging of the population. The 1st step in meeting problems from the demographic transition is organizing the family planning program in an effective way. The very concept family planning should be transferred to family life planning, which includes the family formation period, the family growing period with child education and couple life, and the family reduction period with the older family. The family planning program could retrain its grass roots workers for family health and welfare. The use of effective contraception would preclude the need for induced abortion. The family health program could include diet, nutrition, home environment and sanitation, geriatric diseases, and health services for the aged. Family welfare planning and services are more necessary than ever with the proliferation of the nuclear family and increasing female employment. Population policy must be established on the country level and coordinated with development policy.