Evaluation of the obstetric significance of some pelvic characters in an 18th century British sample of known parity status.

The excavations at Christ Church, Spitalfields (1984-86) produced a sample of 968 human skeletons which were interred between 1729 and 1859. Of these, 387 were recovered in association with coffin plates stating name, age at death, and date of death. There are 138 adult females in the named sample and the obstetric histories of 94 have been reconstructed from historical documentation. Such variables as birth spacing, number of children, and age at first and last births are known for the majority of this sample. Any individual about whose history there is any doubt has been excluded from the analysis. A middle-class group, they were largely of high nutritional status and, by the standards of the day, lived in sanitary and comfortable conditions. Both males and females have a mean age at death of 56 years. The presence or absence, the typology, the severity, the width and the length of the preauricular sulcus, the presence or absence and the number of pits on the dorsal aspect of the pubic body, sulci along the anterior sacrum adjacent to the auricular facet, and the extension of the pubic tubercle were evaluated in relation to the obstetric histories of these females. Statistical analysis has demonstrated a relationship between the presence of pubic tubercle extension and parity status and between the degree of extension and the number of children borne (P < .02). Statistically there is no significant relationship (P > .05) between either the preauricular sulcus or pubic pitting and parity status. Sacral scarring is significantly associated (P < .05) with parity status, but as it was evident in only eight females it has little practical application. Sample sizes are small, and it must be considered that statistical evaluation of larger samples might detect associations between variables not demonstrated here. There is no significant relationship between any of the cortical variants under consideration and age at death.     

Can women remember how many children they have borne? Data from the east Caribbean.

The number of births reported by 786 women of native ancestry on the 1954 census of St. Barthélémy, French West Indies, was compared to the number of births registered to these same women in the records of vital events. The magnitude of the difference between the two numbers was related to a woman's parity and marital status, but not to her age or literacy. In general, the agreement between the two numbers was very high, with the mean of reported parities within 5 per cent of the mean of registered births for all age groups except one, where the difference was 5.6 per cent. The women of St. Barthélémy were well able to remember the number of children they had borne. It appears likely that the discrepancies between reported parities and registered statistics in previous studies are the result of cultural misunderstandings in questionnaires, or perhaps sample decay, rather than of women's memory loss.     

Heliogeophysical correlates of early biodemographic variables in the south of western Siberia

In order to verify associations between solar and geomagnetic activities and perinatal variables the monthly distributions of population characters in Novosibirsk region over the period 1980-2001 were compared by stepwise correlation analysis with monthly averaged physical parameters at lags from 0 to 10 months. Three indices used were as follows: the number of sunspots, solar flux at 10.7 cm wavelength and Ak index measured at local ionospheric station near Novosibirsk city. Official data on the number of single and multiple live births, stillbirths and infant deaths at the age under one year by the type of population and sex were provided by State Statistical Committee. All three physical parameters positively correlated with the number of single births and infant mortality rate and negatively with twin births in both populations, urban and rural, irrespective of lags. The direct association between Ak index and relative number of stillbirths in urban setting was mostly pronounced at a lag of 5 months. The number of live births increased along with Ak index due to the enhanced proportion of female births whereas the number of stillbirths after the increase in solar and geomagnetic activities elevated because of male deaths.     

Novel perspectives on the influence of the lunar cycle on the timing of full-term human births

ABSTRACT

It is claimed by some that the number of births occurring at the time of the full moon is greater than other phases of the lunar cycle; however, many publications fail to substantiate the claim leading to the conclusion it is myth. We tested using a novel approach the null hypotheses: (i) human birth is not lunar cycle-dependent and (ii) the number of births occurring at or around the time of the full moon is not different from the number occurring at the time of the other phases of the lunar cycle. We reviewed the birth records from 1 January 1996 to 16 March 2007 of the obstetric department of our hospital, which was then located in a relatively undeveloped area of Fukutsu city in Fukuoka Prefecture of southern Japan. A total of 1507 births satisfied all inclusion criteria, among others, being full-term and following spontaneously initiated labor. When the birth data were analyzed as done by other investigators, i.e. total number of births per lunar day, lunar phase was not found to be influential. However, more detailed analyses on the subset of babies born specifically during the nighttime hours (N = 362) revealed the number of births varied in relation specifically to the changing amount of moonlight during the nighttime at different stages of the lunar cycle, with highest number of births at or around the time of the full moon. In contrast, analyses on the subset of babies born specifically during the daytime hours (N = 377) revealed the number of births varied in relation specifically to the changing amount moonlight during the daytime at different stages of the lunar cycle, with the highest number of births at or around the time of the new moon. The initiation and culmination of human birth are typically a nocturnal process. The findings of this investigation are consistent with the hypothesis natural nighttime parturition is influenced by lunar phase, particularly the full moon, and, thus, they are consistent with the belief the moon exerts an affect upon the timing of human birth. We speculate the long-hold belief of the association between birth and lunar phase may be based on historical observations that in the absence of artificial light at night nocturnal births occurred in elevated number when the full moon brightly illuminated the nighttime sky.     

Prevalence of esophageal atresia among 18 international birth defects surveillance programs

BACKGROUND: The prevalence of esophageal atresia (EA) has been shown to vary across different geographical settings. Investigation of geographical differences may provide an insight into the underlying etiology of EA. METHODS: The study population comprised infants diagnosed with EA during 1998 to 2007 from 18 of the 46 birth defects surveillance programs, members of the International Clearinghouse for Birth Defects Surveillance and Research. Total prevalence per 10,000 births for EA was defined as the total number of cases in live births, stillbirths, and elective termination of pregnancy for fetal anomaly (ETOPFA) divided by the total number of all births in the population. RESULTS: Among the participating programs, a total of 2943 cases of EA were diagnosed with an average prevalence of 2.44 (95% confidence interval [CI], 2.35–2.53) per 10,000 births, ranging between 1.77 and 3.68 per 10,000 births. Of all infants diagnosed with EA, 2761 (93.8%) were live births, 82 (2.8%) stillbirths, 89 (3.0%) ETOPFA, and 11 (0.4%) had unknown outcomes. The majority of cases (2020, 68.6%), had a reported EA with fistula, 749 (25.5%) were without fistula, and 174 (5.9%) were registered with an unspecified code. CONCLUSIONS: On average, EA affected 1 in 4099 births (95% CI, 1 in 3954–4251 births) with prevalence varying across different geographical settings, but relatively consistent over time and comparable between surveillance programs. Findings suggest that differences in the prevalence observed among programs are likely to be attributable to variability in population ethnic compositions or issues in reporting or registration procedures of EA, rather than a real risk occurrence difference. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc.     

The lunar cycle,sunspots and the frequency of births in Germany, 1920–1989

Based on multivariate linear regression models, we analyze the effect of the lunar cycle and the number of sunspots occurring on a particular day on the number of births using social security data and controlling for a number of other potential confounders. The daily numbers of births between 1920 and 1989 have been calculated from the full sample of individuals who have been registered at least once in the German social security system. While the lunar cycle does not affect the number of births, the number of sunspots is positively correlated to the number of births. The empirical results may be explained by medical technological progress making natural influences on births less important over time. This interpretation is supported by the results on the intertemporal influence of weekends and holidays on the frequency of daily births.     

Heliogeophysical correlates of early biodemographic variables in the South of Western Siberia

In order to verify associations between solar and geomagnetic activities and perinatal variables, the monthly distributions of population characters in Novosibirsk Region over the period 1980–2001 were compared by stepwise correlation analysis with monthly averaged physical parameters at lags from 0 to 10 months. The three indices were: number of sunspots, solar flux at 10.7 cm wavelength, and A _k index measured at a local ionospheric station near the city of Novosibirsk. Official data on the numbers of single and multiple live births, stillbirths and infant deaths at the age under one year indicating the type of population and gender were provided by the State Statistical Committee. All three physical parameters positively correlated with the number of single births and infant mortality rate and negatively with twin births in urban and in rural populations, irrespective of lags. The direct association between A _k and the relative number of stillbirths in urban setting was mostly pronounced at a lag of 5 months. The number of live births increased along with A _k owing to the enhanced proportion of girls born, whereas the number of stillbirths after the rise in solar and geomagnetic activities increased because of boy deaths.     

Effects of management practices on the timing of captive chimpanzee births

Most wild and captive nonhuman primates give birth nocturnally. Circadian rhythm mechanisms are a principal determinant of the nonrandom initiation of labor, but it has been suggested that the decreased human activity and increased seclusion over the weekend in laboratory primate colonies may result in an effect whereby births are confined mainly to the quiet periods. This study tests for such an effect in the timing of 153 live, term births in chimpanzees (Pan troglodytes) housed in three institutions with various management practices. Eighty-four percent of births occurred nocturnally, and peak delivery time was between 2400 and 0700 hours. When the total number of births was examined, significantly fewer births occurred on Wednesdays and Thursdays, during the mid-week peak in colony activity, and significantly more births occurred on Sundays and Mondays. In facilities having marked alterations between weekday and weekend activity, significantly more births occurred Sunday and Monday. In the colonies where weekend and weekday surveillance and activity were similar, births were more evenly distributed throughout the week. These data suggest that parturition may be inhibited by routine colony activities that are perceived as stressful by some animals, and that the decreased activity and increased privacy on weekends may allow relaxation of parturient females, resulting in delivery during or immediately following the weekend. Colony managers should minimize colony activities that are potentially stressful to prepartal females in order to reduce risks to the fetus that may occur with delay or disruption of normal parturition. © 1992 Wiley-Liss Inc.     

First presidential addressbehavior genetics association April 6, 1973

Abstract

The number of births reported by 786 women of native ancestry on the 1954 census of St. Barthélémy, French West Indies, was compared to the number of births registered to these same women in the records of vital events. The magnitude of the difference between the two numbers was related to a woman's parity and marital status, but not to her age or literacy. In general, the agreement between the two numbers was very high, with the mean of reported parities within 5 per cent of the mean of registered births for all age groups except one, where the difference was 5.6 per cent. The women of St. Barthélémy were well able to remember the number of children they had borne. It appears likely that the discrepancies between reported parities and registered statistics in previous studies are the result of cultural misunderstandings in questionnaires, or perhaps sample decay, rather than of women's memory loss.     

Changes in maternal risk factors and their association with changes in cesarean sections in Norway between 1999 and 2016: A descriptive population-based registry study

BackgroundIncreases in the proportion of the population with increased likelihood of cesarean section (CS) have been postulated as a driving force behind the rise in CS rates worldwide. The aim of the study was to assess if changes in selected maternal risk factors for CS are associated with changes in CS births from 1999 to 2016 in Norway.Methods and findingsThis national population-based registry study utilizes data from 1,055,006 births registered in the Norwegian Medical Birth Registry from 1999 to 2016. The following maternal risk factors for CS were included: nulliparous/≥35 years, multiparous/≥35 years, pregestational diabetes, gestational diabetes, hypertensive disorders, previous CS, assisted reproductive technology, and multiple births. The proportion of CS births in 1999 was used to predict the number of CS births in 2016. The observed and predicted numbers of CS births were compared to determine the number of excess CS births, before and after considering the selected risk factors, for all births, and for births stratified by 0, 1, or >1 of the selected risk factors. The proportion of CS births increased from 12.9% to 16.1% (+24.8%) during the study period. The proportion of births with 1 selected risk factor increased from 21.3% to 26.3% (+23.5%), while the proportion with >1 risk factor increased from 4.5% to 8.8% (+95.6%). Stratification by the presence of selected risk factors reduced the number of excess CS births observed in 2016 compared to 1999 by 67.9%. Study limitations include lack of access to other important maternal risk factors and only comparing the first and the last year of the study period.ConclusionsIn this study, we observed that after an initial increase, proportions of CS births remained stable from 2005 to 2016. Instead, both the size of the risk population and the mean number of risk factors per birth continued to increase. We observed a possible association between the increase in size of risk population and the additional CS births observed in 2016 compared to 1999. The increase in size of risk population and the stable CS rate from 2005 and onward may indicate consistent adherence to obstetric evidence-based practice in Norway.

In a population-based study, Ingvild Nedberg and colleagues investigate the relationship between maternal risk factors and changes in rates of cesarean section births in Norway.     

The rate of preterm twin births (22-27 weeks) as a criterion for measuring the quality of prenatal care.

While the true figures are not well established, outcomes of twin pregnancies are directly dependent on a small number of preterm births between 22 and 27 weeks. Observation of perinatal outcomes in twin pregnancies yields two contradictory results. Firstly, it shows an improvement in perinatal mortality figures. Secondly, it reveals an increase in the rates of preterm deliveries. These findings result from the observation of 783 twin pregnancies followed and delivered in a level 3 perinatal centre in Paris between 1993 and 1998. Women followed since the beginning of pregnancy through the outpatient clinic of the institution are included in this number, as are women who were referred or transferred to the centre at a later date due to complications, This analysis reflects the influence of two contrasting policies. The first, and less recent policy is devoted to the prevention of preterm births, and is reflected by the low number of extremely preterm deliveries at 22-32 weeks. The second is the effect of our new approach to the prevention of foetal deaths in relation to foetal growth retardation in twins which has resulted in increased medical intervention such as the induction of labour or scheduled Caesarean birth. This has resulted in an increase in twin preterm births from 33 to 36 weeks, with the expected result of fewer foetal deaths.     

Race differences in pubic symphyseal aging patterns in the male

A well-documented multiracial sample of 704 male pubic bones allows for rigorous testing for racial differences in pubic symphyseal metamorphosis. The relationship between estimated age (using a modified Todd six-stage system) and age is examined as a function of race (White, Black, Mexican). One set of analyses incorporates linear regression models, while a second set does not impose such structure on the relationship. The latter analyses incorporate analysis of variance and related procedures. Significant differences in age are found across racial groups; it is seen that Blacks and Mexicans with advanced pubic symphyseal patterns tend to have lower ages than Whites. We do not address the question of causality, which may involve genetic factors and/or environmental variables such as diet, alcoholism, or drug abuse.     

Season of Birth in Schizophrenia in the Mexico City Area: Comparison with General Population

The relationship between seasonal changes and mental disorders has been extensively studied in the northern and southern hemispheres. In both cases, the results show that there is a higher rate of schizophrenic births during the winter months. The present study attempts to prove the existence of this phenomena in Mexico City, an area that does not undergo extreme weather variations throughout the year. A total of 2,288 schizophrenic patients was considered for this study. Their date of birth was compared to that of the general population of the Mexico City area, a total of 4,848,119 individuals. The number of births was evaluated according to the number of days in each month. The distribution of the births of schizophrenics was compared to the reference population by means of a Kolmogorov-Smirnov test and a X 2 contrast. The annual rhythm of births of schizophrenics was determined through an analysis of the Estimated Seasonal Component. There was a slight, non-significant increment in schizophrenic births in December and autumn, as compared with the general population birth rate. Interestingly, it was found that births in the control population decreased significantly in December when compared with all the other months. Results were discussed in relation to the geographical location of Mexico, which lies in a tropical zone, and as a consequence minimal seasonal effects.     

Season of Birth in Schizophrenia in the Mexico City Area: Comparison with General Population

The relationship between seasonal changes and mental disorders has been extensively studied in the northern and southern hemispheres. In both cases, the results show that there is a higher rate of schizophrenic births during the winter months. The present study attempts to prove the existence of this phenomena in Mexico City, an area that does not undergo extreme weather variations throughout the year. A total of 2,288 schizophrenic patients was considered for this study. Their date of birth was compared to that of the general population of the Mexico City area, a total of 4,848,119 individuals. The number of births was evaluated according to the number of days in each month. The distribution of the births of schizophrenics was compared to the reference population by means of a Kolmogorov-Smirnov test and a X 2 contrast. The annual rhythm of births of schizophrenics was determined through an analysis of the Estimated Seasonal Component. There was a slight, non-significant increment in schizophrenic births in December and autumn, as compared with the general population birth rate. Interestingly, it was found that births in the control population decreased significantly in December when compared with all the other months. Results were discussed in relation to the geographical location of Mexico, which lies in a tropical zone, and as a consequence minimal seasonal effects.     

Seasonality of triplet births in the United States

Birth data on 1050 sets of triplets delivered in the United States from 1985 to 1988 were analyzed to establish whether seasonal variations in the number of triplet births occur. These data were compared to live birth data from the entire United States population over a similar period; the US data exhibit a seasonal variation with a peak in late summer. Seasonality in the number of triplet births was noted, and it differed significantly (p = 0.01) from that of the entire US population. A large peak in triplet births was seen in the spring (April-May) and a smaller peak in late summer (August-September). Only minor differences in these trends could be observed when triplet data were stratified by cause of pregnancy (spontaneous versus drug-induced ovulation) or corrected for the shorter gestations of triplet pregnancies.     

Assessing the influence of occupational and physical activity on the rate of degenerative change of the pubic symphysis in Portuguese males from the 19th to 20th century

Among the many factors suggested as potential sources of variation in the rate of ageing of the pubic symphysis is occupational/physical activity, but this has yet to be demonstrated. This study's main goal is to determine whether occupational/physical activity influences the aging process in the pubic symphysis. We analyzed a sample of 161 males (18-96 years) from two Portuguese identified skeletal collections, where age-related features were recorded in the pubic symphysis as absent/present. The sample was divided in two groups according to the occupation of the individuals (manual and non-manual) and in two groups according to the femoral robusticity index (robust and gracile). The manual and robust groups represent individuals with more physically demanding occupations while the non-manual and gracile groups represent less physically demanding occupations. The possible influence of occupational/physical activity on the rate of ageing was evaluated by comparing the transition age for each age-related feature, between the two groups, using logistic regression. Only the ligamentous outgrowths on the ventral beveling showed a statistically significant younger age in the robust group, indicating a possible faster rate or early timing of change in the individuals with a more physically demanding activity compared with their gracile counterparts. Thus, these results do not provide significant support to the hypothesis that individuals with a greater demanding occupation or physical activity show greater pubic symphysis degeneration. Further testing of this hypothesis in other samples with individuals from known occupation is required.     

The prevalent use of contraception among teenagers in Denmark and the corresponding low pregnancy rate

In Denmark the number of births and induced abortions among teenagers has reduced and teenage parenthood is now rare. This paper evaluates the correlation between this observed fertility and reported sexual and contraceptive behaviour. In 1989 a sample of 16-20-year-olds in Denmark was selected at random and personally interviewed about sexual and contraceptive behaviour. Ninety-five per cent of the young women who had experienced sexual intercourse used contraception at the most recent sexual intercourse. In order to support the validity of this finding a model was developed to estimate an expected number of conceptions in the age groups concerned. The model included both the information on coital frequency and use of contraception from the questionnaire and available efficacy rates on contraception. The estimates derived by the model were compared with the registered number of births and induced abortions derived from public registers. The analysis revealed a high accordance between the estimated number of conceptions and the registered number of births and induced abortions for each age group. This underlines the validity of the data on sexual and contraceptive behaviour sampled among teenagers in Denmark. The findings indicate that contraceptive failure is a much greater problem than non-use of contraception for teenagers in Denmark.     

Studies of androgen metabolism and action in cultured hair and skin cells

In order to study the mechanism of action of androgen on pubic and scalp hair, we established these and skin epithelial cells in culture. Because 5 alpha-reductase has been suspected of playing a role in hair growth, we tested the possibility that these cells differ in their pattern of androgen metabolism. Furthermore, we tested the hypothesis that androgen exerts its distinctive effects on these hairs by differentially regulating keratin or DNA synthesis. Anagen hairs of men and women were plucked from the pubis or scalp vertex and were studied using an epithelial cell culture technique. DHT formation from [3H]T cultured skin cells increased in the following order: epidermal less than scalp less than pubic less than fibroblasts = 0.8:2.8:8.1:71%/mg DNA/min, respectively. Androstanediols were minor [3H]DHT metabolites of all these skin cell types. The only feature that distinguished among the cultured epithelial cells was the ratio of apparent 5 alpha-reductase (5 alpha-R) to 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) activity: this was significantly greater (P less than 0.05) in cultured pubic hair cells than in scalp hair or epidermal cells. Cultured scalp and pubic hair cells resembled freshly plucked hair follicle cells in their keratin pattern. 46, 50, 56 and 58 kdalton bands constituted 99% of the total keratins. This keratin pattern and the polygonal cell shape were also similar to that of cultured epidermal cells. However, this keratin pattern was distinctly different from that of hair shafts which have 53 and 63 kdalton keratins. Dihydrotestosterone did not affect the keratin pattern, pattern of incorporation of [35S]cysteine or [35S]methionine, or rates of protein synthesis or cell proliferation in cultured hair cells. Although the higher apparent 5 alpha-R/17 beta-HSD ratio of cultured pubic than of scalp hairs is compatible with modulation of hair development by androgen, these studies militate against the possibility that androgens directly affect hair cell proliferation or protein synthesis in pubic or scalp hair.     

Identification of individual adult female Javan lutungs (Trachypithecus auratus sondaicus) by using patterns of dark pigmentation in the pubic area

In a series of field surveys of wild Javan lutungs (Trachypithecus auratus sondaicus) conducted at Pangandaran Nature Reserve in West Java, Indonesia, from 2011 to 2012, we tried to use a method of individual identification by using individual-specific patterns of dark pigmentation in the pubic area. During the 2011 dry season, we used a digital SLR camera with a 400-mm telephoto lens to photograph the pubic area of each individual of a habituated group. These photographs were the basis for identifying 14 different adult females. During the rainy season of 2011 and the dry season of 2012, we checked the presence/absence of each of the identified individuals and found that these patterns were stable, at least during our study period. We found that two adult females and one adult female disappeared from the subject group between the first and second and between the second and third surveys, respectively, and that one adult female gave birth between the first and second surveys, but the infant had disappeared from the group between the second and third surveys. We could not confirm the validity of the method for juvenile females because of the dense white hair in their pubic areas and the fact that few individuals had clear patterns. Furthermore, we could not use this method for males because of the lack of pigmentation in the pubic area. As patterns of pigmentation in the pubic area are known to be present in other Trachypithecus species, our method can be useful for identification of individual adult females of these species, on which few individual-based behavioral studies have been conducted. Collecting individual-based behavioral data would enable us to track the presence of individuals in groups or movements between groups; determine the effects of social rank and age on within-group competition and copulation; and examine population data.     

On the twin risk in autism

Autism is considered by many to be the most strongly genetically influenced multifactorial childhood psychiatric disorder. In the absence of any known gene or genes, the main support for this is derived from family and twin studies. Two recent studies (Greenberg et al. 2001; Betancur et al. 2002) suggested that the twinning process itself is an important risk factor in the development of autism. If true, this would have major consequences for the interpretation of twin studies. Both studies compared the number of affected twin pairs among affected sib pairs to expected values in two separate samples of multiplex families and reported a substantial and significant excess of twin pairs. Using data from our epidemiological study in Western Australia, we investigated the possibility of an increased rate of autism in twins. All children born between 1980 and 1995 with autism, Asperger syndrome, or pervasive developmental disorder not otherwise specified (PDD-NOS) were ascertained. Of the 465 children with a diagnosis, 14 were twin births (rate 30.0/1,000) compared to 9,640 children of multiple births out of a total of 386,637 births in Western Australia between 1980 and 1995 (twin rate weighted to number of children with autism or PDD per year 26.3/1,000). These data clearly do not support twinning as a substantial risk factor in the etiology of autism. We demonstrate that the high proportion of twins found in affected-sib-pair studies can be adequately explained by the high ratio of concordance rates in monozygotic (MZ) twins versus siblings and the distribution of family size in the population studied. Our results are in agreement with those of two similar studies by Croen et al. (2002) in California and Hultman et al. (2002) in Sweden.