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At least 19 recordsLinked to original sources
PubMed1984

Fetal mortality in oral cleft families (VII): Birth intervals.

Birth intervals in sibships of oral cleft probands are analysed to detect prolonged delays between successive pregnancies. Such intervals are useful indicators of undetected fetal mortality. The present study indicates that the average interval for 462 cleft families in Indiana is 30.61 months. The average interval leading to the birth of a cleft child is 33.94 and is significantly greater than the average interval for the entire sample. Although the contraception status of the Indiana population is not known, the significantly greater delay preceding the birth of a cleft child is indicative of a cause other than contraception. This finding is in agreement with the report by Drillien et al. (1966) that abnormal conceptions occur more frequently adjacent to cleft offspring. It is interesting that some increase in the average interval is also noted in the present study immediately following the birth of a cleft child. Such delays occurring both preceding and following the birth of a cleft child (in contrast to smaller intervals for other pregnancies in the same sibships) may indicate excessive fetal wastage due to a combination of genetic and environmental factors.

Birth Intervals↗
PubMed1996

[Birth intervals and birth of low weight infants in Benin].

Low birthweight is a public health problem in Benin but its etiology remains unclear. Studies in industrial countries suggest several risk factors including the interval between pregnancies or child spacing. The purpose of this cohort study was to assess the relationship between pregnancy interval and low birthweight in Benin. Data were collected from a total of 2,862 multiparous pregnant women randomly recruited in 1991 at the time of their first prenatal care visit to maternity units in Cotonou, Benin. Sociodemographic information and obstetrical history were obtained by interviewing the mother and reviewing delivery records. About 15% of the women recruited delivered low birthweight children. The relative risks of preterm birthweight and intrauterine growth retardation was calculated in function of three pregnancy intervals: less than 12 months, 12 to 23 months, and 24 to 34 months. It was 1.31 (1.00-1.75), 1.00 (0.70-1.02)) and 0.77 (0.60-0.87) respectively for preterm birthweight and 1.27 (1.03-1.64), 1.17 (0.79-1.39) and 0.79 5 (0.57-0.87) respectively for intrauterine growth retardation. Logistic regression analysis taking into account sociodemographic factors and previous obstetrical history did not show a significant correlation between pregnancy interval and preterm low birthweight or between pregnancy interval and intrauterine growth retardation. Maternal nutritional status, maternal age, number of previous births, and education level were correlated with low birthweight.

Adult↗
PubMed1993

Selected determinants of fertility in Vietnam: age at marriage, marriage to first birth interval and age at first birth.

Data from the 4172 women aged 15-49 interviewed in the 1988 Vietnamese Demographic and Health Survey were used to examine age at marriage, marriage to first birth intervals and age at first birth. Differences between urban and rural areas, northern and southern provinces and by education of the women were analysed. The majority of the women had their first birth before age 20, but women with secondary education had a significantly higher age at first birth than those with little or no education, and women from the north had a significantly higher age at first birth than women from the south. Rural women and those with little or no education married at significantly younger ages than urban women and those with secondary education; these education effects were confirmed in a rural subsample of women. Women from rural areas and from the north had significantly shorter marriage to first birth intervals than urban women and those from the south, but there were no significant effects related to education.

Adolescent↗
PubMed1999

The association of birth interval, maternal age and season of birth with the fertility of daughters: a retrospective cohort study based on family reconstitutions from nineteenth and early twentieth century Quebec.

In a historical follow-up study, we evaluated the association of the fertility of daughters with five perinatal factors: short (< 15 months) or long (> or = 45 months) preceding birth interval, low (< or = 20 years) or advanced (> or = 40 years) maternal age and season of birth. We used data concerning 2062 women married before the age of 31 and born in the Saguenay region of Quebec, Canada, between 1850 and 1899. Time between the wedding and first birth was used for the estimation of differences in fertility. Using logistic regression and controlling for several potential confounders, we found a slightly increased risk of monthly failure of conception for daughters born after a short but not for those born after a long birth interval (odds ratios [ORs] 1.09 [0.89, 1.33] and 0.87 [0.65, 1.16], respectively, with intervals between 21 and 32 months as the reference category). A slightly increased risk of conceptive failure was also seen for daughters of younger and older mothers (ORs 1.08 [0.89, 1.30] and 1.11 [0.91, 1.35], respectively, compared with maternal age between 24 and 30 years as the reference category). Fertility varied by season of birth (P = 0.02), with summer-born daughters having lowest and winter-born daughters having highest fertility. These results are consistent with the idea that maternal factors before or around birth play a role in the aetiology of reduced fertility. The data, however, do not unequivocally support the hypothesis that gave rise to the present study, namely that ovarian development may be disturbed after conception in conditions with an increased risk of maternal menstrual cycle irregularities.

Adolescent↗
PubMedDate not supplied

Is the reduction of birth intervals an efficient reproductive strategy in traditional Morocco?

Birth interval lengths are analysed from reproductive life histories of 517 Berber peasant women of the region of Marrakesh (Southern Morocco), whose fertility developed in a full traditional context. The high mortality rates associated with short birth intervals indicate that a rapid succession of births is detrimental to the progeny. The reproductive efficiency of the traditional propensity to a large family size is therefore examined by means of two different evaluations of reproductive success: the 'absolute' reproductive success (the absolute number of offspring surviving to maturity) and the 'relative' reproductive success (the proportion of live born surviving to maturity). The first shows that close pregnancies increase the fertility rate to such an extent that the associate higher number of deaths is more than compensated for, so that the women practising short birth intervals produce more surviving offspring than the others by the end of their reproductive life. The second shows that the probability of survival is directly associated with birth interval length, the efficiency of the reproductive process being therefore greater as birth intervals grow. It is suggested that these two behaviours are not contradictory, and that they represent two successive steps of the same reproductive adjustment to evolving environmental conditions.

Aged↗
PubMed1989

Determinants of birth intervals in Sudan.

Using individual birth history data from the Sudan Fertility Survey, 1979, parity-related differences in fertility are demonstrated, as well as differences between socioeconomic groups. Rural women, women with no education and those married to uneducated husbands show rapid parity progression and its cumulative effects on fertility which are consistent over all birth intervals. Urban women, women with some education and those married to educated husbands, however, go rapidly through their second and third birth intervals and then more slowly at higher parities. A limitation of the study was the inability to control fully for the effects of breast-feeding and contraception. There is evidence for a reduction in high parity births, starting in the 1970s.

Birth Intervals↗
PubMed1997

Birth interval and the sex of children in a traditional African population: an evolutionary analysis.

Birth interval is a major determinant of rates of fertility, and is also a measure of parental investment in a child. In this paper the length of the birth interval in a traditional African population is analysed by sex of children. Birth intervals after the birth of a boy were significantly longer than after the birth of a girl, indicating higher parental investment in boys. However, in women of high parity, this differential disappeared. Birth intervals for women with no son were shorter than for those with at least one son. All these results are compatible with an evolutionary analysis of reproductive decision-making. First born sons have particularly high reproductive success, daughters have average reproductive success and late born sons have low reproductive success. The birth interval follows a similar trend, suggesting that longer birth intervals represent higher maternal investment in children of high reproductive potential.

Adult↗
PubMed2002

Birth order, birth interval, and deviant sexual preferences among sex offenders.

We investigated whether birth order and birth interval are associated with phallometric responding among 168 sex offenders. Based on the immunoreactivity hypothesis, we predicted that a larger number of older brothers and a shorter birth interval between the offenders and their next older brothers would be associated with more deviant responding. Results showed that a larger number of older brothers (but not older sisters, younger brothers, or younger sisters) was associated with more deviant responding on the Most Deviant Index, a general measure of sexual deviance. A larger number of older brothers was associated with arousal to nonsexual violence against women and children, but contrary to expectation, the same association was also found for the number of younger brothers. A short birth interval with the next older brother was associated with greater relative arousal to nonsexual violence, but the correlation with the Most Deviant Index did not reach statistical significance. Overall, results were consistent with the main predictions, but the effects of birth order and birth interval were mostly restricted to arousal to nonsexual violence. Birth order and birth interval were not associated with pedophilic interests or gender preferences.

Adult↗
PubMedDate not supplied

Preceding birth intervals and child survival: searching for pathways of influence.

The importance of the length of preceding birth intervals for the survival chances of young children has been established, but the debate concerning the causal biomedical or behavioral mechanisms continues. This article uses data from 17 Demographic and Health Surveys to investigate the effect of birth intervals on child mortality: Anthropometry of children, recent morbidity of children, and use of health services are examined in addition to child survival data for children born in the five years before the survey. Various methodological approaches are used to investigate the relative importance of the postulated mechanisms linking birth intervals and child survival. Short preceding birth intervals are associated with increased mortality risks in the neonatal period and at 1-6 months of age, and, to a much lesser extent, at 7-23 months of age. The effects of short birth intervals on nutritional status are rather moderate, and there is a weak relationship with lower attendance at prenatal care services. No consistent relationship exists between the length of birth intervals and other health status or health-service utilization variables. The results indicate that prenatal mechanisms are more important than postnatal factors, such as sibling competition, in explaining the causal nature of the birth interval effect.

Anthropometry↗
PubMed1993

Age of marriage and length of the first birth interval in a traditional Indian society: life table and hazards model analysis.

The length of the first birth interval is one of the strongest and most persistent factors affecting fertility in noncontracepting populations, with longer intervals usually associated with lower fertility. Compared to Western society, the average length of the first birth interval is much longer in traditional Indian society. Yet Indian fertility rates are higher because of either ineffective family planning procedures or deliberate nonuse of birth control and because of the high proportion of the population that is married. Here, we examine the effects of various sociodemographic covariates (with an emphasis on the role of age at marriage) on the length of the first birth interval for two states of India: Assam and Uttar Pradesh. Life table and multivariate hazards modeling techniques are applied to the data. Covariates such as age at marriage, present age of mother, female's occupation, family income, and place of residence have strong effects on the variation of the length of the first birth interval. For each subgroup of females (classified according to different levels of the covariates), the median length of the first birth interval for the Assam (Bengali-speaking) sample is shorter than that of the Uttar Pradesh (Hindi-speaking) sample.

Adolescent↗
PubMed1996

Birth interval and pregnancy outcome.

A cross-sectional study was conducted from September to March 1993 at maternity ward of Jimma Hospital to asses the pattern and determinants of birth interval and the role of contraceptive in influencing the length of birth interval. The information was collected by use of pre-tested questionnaire from 415 mothers by three midwives trained for this purpose. The variables examined were: information on parity, use of contraceptive methods during the preceding birth intervals, breast feeding and some demographic variables such as age, martial status, education. Pregnancy outcome variables such as, live births, stillbirths, abortion and infant deaths. Slightly over seventy five per cent of the study subjects were aged 20-29 years, 59% and 27% were para 2-3 and 4-5 respectively. In more than 81% of the subjects, the birth interval was less than three years with a mean birth interval of 22.1 months. Approximately two per cent used contraceptive when the birth interval was 12 months and less. Stillbirth and early neonatal deaths accounted for 3.2% and 6.9% respectively. Based on the findings, we underscore the importance of birth spacing using the available family planning methods to promote safe motherhood and achieve better child survival.

Adult↗
PubMed1990

Birth intervals and childhood mortality in rural Bangladesh.

This study investigates the relationship between birth intervals and childhood mortality, using longitudinal data from rural Bangladesh known to be of exceptional accuracy and completeness. Results demonstrate significant but very distinctive effects of the previous and subsequent birth intervals on mortality, with the former concentrated in the neonatal period and the latter during early childhood. The impact of short birth intervals on mortality, however, is substantially less than that found in many previous studies of this issue, particularly for the previous birth interval. The findings are discussed in terms of the potential for family planning programs to contribute to improved child survival in settings such as Bangladesh.

Bangladesh↗
PubMed1993

Analysis of birth intervals in India's Uttar Pradesh and Kerala States.

Life tables of birth intervals and median birth intervals in two Indian states, Uttar Pradesh and Kerala, were computed for several subgroups of the study population. Multivariate hazards modelling technique was used to examine the net effect of each of the variables studied. The results show a substantial effect of socioeconomic variables in child-spacing after controlling for the major intermediate variables.

Adolescent↗
PubMed1990

Birth interval among breast-feeding women not using contraceptives.

One hundred twelve Orthodox Jewish mothers were surveyed by means of questionnaire about birth interval in relationship to formula-feeding (n = 30) and breast-feeding (n = 236) experiences in the absence of birth control. Analyses indicate that mothers who breast-fed have longer birth intervals than those who did not. Moreover, data obtained from the same mothers show that birth intervals preceded by breast-feeding were longer than those preceded by formula-feeding of the previous infant. For those mothers who breast-fed, there was significant positive correlation between duration of breast-feeding and the length of lactational amenorrhea and total birth interval. The age at which night feeding was terminated had corresponding but less strong associations with lactational amenorrhea and total birth interval.

Adult↗
PubMed2000

The effect of birth interval on malnutrition in Bangladeshi infants and young children.

This study was undertaken to investigate the independent effect of the length of birth interval on malnutrition in infants, and children aged 6-39 months. Data for this study were drawn from a post-flood survey conducted during October-December 1988 at Sirajganj of the Sirajgani district and at Gopalpur of the Tangail district in Bangladesh. The survey recorded the individual weights of 1887 children. Cross-tabulations and logistic regression procedures were applied to analyse the data. The proportion of children whose weight-for-age was below 70% (moderate-to-severely malnourished) and 60% (severely malnourished) of the NCHS median was tabulated against various durations of previous and subsequent birth intervals. The odds of being moderately or severely malnourished were computed for various birth intervals, controlling for: the number of older surviving siblings; maternal education and age; housing area (a proxy for wealth); age and sex of the index child; and the prevalence of diarrhoea in the previous 2 weeks for the index child. About one-third of infants and young children were moderately malnourished and 15% were severely malnourished. The proportion of children who were under 60% weight-for-age decreased with the increase in the length of the subsequent birth interval, maternal education and housing area. The proportion of malnourished children increased with the number of older surviving children. Children were at higher risk of malnutrition if they were female, their mothers were less educated, they had several siblings, and either previous or subsequent siblings were born within 24 months. This study indicates the potential importance of longer birth intervals in reducing malnutrition in children.

Adult↗
PubMed1993

Short birth intervals: the experience of Bangladeshi immigrants to the United Kingdom, 1974 through 1984.

Linked maternity data were used to calculate birth intervals from records of 7129 consecutive singleton births to Bangladeshi mothers who delivered in the London borough of Tower Hamlets from 1974 through 1984. During this period, there was active migration of women from Bangladesh, the majority coming to the United Kingdom as brides or young wives. Risk of a subsequent birth was calculated using life tables, and results were compared to national data from Bangladesh and the United Kingdom. The risk of a subsequent birth within 12 and 18 months for Bangladeshi women was twice that reported nationally for women in Bangladesh or in the United Kingdom, despite a demonstrable underestimation inherent in the method. The risk of short birth intervals was lower in the first 5 years than in the later years covered by the investigation. Short intervals stress maternal and infant health and are preventable. Possible explanations for the unusual excess of very short birth intervals include: (1) the wide availability of artificial milk in a community that has traditionally used breast-feeding as the main method of spacing pregnancies and (2) confusion regarding appropriate postnatal contraception in a young, healthy married population.

Bangladesh↗