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Results for “First Birth”

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At least 19 recordsLinked to original sources

PubMedDate not supplied

Age at return marriage and timing of first birth in India's Uttar Pradesh and Kerala states.

The study investigates the relationship between age at marriage and the length of first birth interval in two states of India: Uttar Pradesh and Kerala. Life tables of first-birth intervals and median first-birth intervals are computed for several subgroups of the study population. Multivariate hazards modelling technique is used to study the net effect of age at marriage, controlling for a multiple of socioeconomic factors. The result shows that the average first-birth interval varies by age at marriage and is much longer in Uttar Pradesh than in Kerala.

Adolescent↗

PubMed2024

Causal effect of the age at first birth with depression: a mendelian randomization study.

BACKGROUND: This study aimed to explore the causal relationship between age at first birth (AFB) and depression. METHODS: Using the univariable Mendelian randomization (UVMR) and multivariable Mendelian randomization (MVMR) methods to examine the potential correlation between age at first birth (AFB) and major depressive disorder and postpartum depression. A public database was used to obtain the genome-wide association studies (GWAS) summary data. We put inverse-variance-weighted (IVW) as the primary method in Mendelian randomization (MR) analysis and used sensitivity analysis to confirm the robustness of our result. RESULTS: We found a significant causal association between AFB and major depressive disorder by using the IVW algorithm (odd ratio [OR] 0.826; 95% confidence interval [CI] 0.793 - 0.861; P = 4.51 × 10- 20). MR-Egger, weighted median, simple mode and weighted mode method concluded the same result (P < 0.05). During the sensitivity analysis, the heterogeneity test (Q-value = 55.061, df = 48, P = 2.81 × 10- 01, I2 = 12.82%) and the leave-one-out plot analysis confirmed the stability of the results. The outcomes of the pleiotropy test (MR-Egger intercept = 8.932 × 10- 3. SE = 6.909 × 10- 3. P = 2.02 × 10- 01) and MR_PRESSO global test (P = 2.03 × 10- 01) indicated there is no pleiotropy. CONCLUSION: There is solid evidence that a higher age at first birth is associated with a lower risk of major depressive disorder.

Humans↗

PubMedDate not supplied

Marriage, remarriage, marital disruption and age at first birth.

Out-of-wedlock pregnancy, especially for a teenager, and even more for a black teenager, hastens early marriage. The younger the age at first birth, the likelier that the first marriage will dissolve. White women are more likely than black women to remarry. Women under 20 at first birth are more likely to have their second marriage dissolve.

Adolescent↗

PubMedDate not supplied

[Age at the time of the first birth: a variable with simple, double, or triple significance in breast cancer studies].

I.--The inverse relationship of risk with parity is one of the earliest known features of the epidemiology of human mammary cancer. But recently knowledge of this relationship was refined when Mac Mahon and his colleagues found that the protective effect is actually correlated to the age of the mother at the first birth rather than to the total number of children, so that a woman who has a child before the age of 18 is one third as likely to suffer breast cancer in later life as a woman first delivered at 35. II.--A study was undertaken in the Centre Francois Baclesse on the hypothesis that age at first birth may also be related to the age of the patient at clinical onset of the mammary malignancy. One would expect to find a retardative effect of early delivery since this factor was found to be protective as far as mammary cancer risk is concerned. The conclusions of our investigations are in complete opposition to the original hypothesis: in our series, breast cancer appears to occur significantly earlier in women whose first delivery occurred early. III.--Thus the same process appears to be protective as far as total mammary cancer risk is concerned but accelerating as far as age at tumor onset is concerned. These apparently inconsistent observations led to the hypothesis that both studies might express the same biologic process which, in the case of early delivery, inhibits the mechanism of carcinogenic induction and therefore reduces the total number of cancer but which subsequently quickens the evolution of the inducted disease. Such a conjecture implies that breast cancer should be more severe following early first birth. The analysis of our series, as well as the series of Ontario Cancer Clinics, substantiates this hypothesis. But these conclusions are built on indirect proofs or direct proofs which are still short of statistical significance.

Adolescent↗

PubMed1978

Age and marital status at first birth and the pace of subsequent fertility.

Taking care to minimize the truncation bias inherent in cross-sectional data and controlling for other variables, this paper demonstrates the strong effects of both age and marital status at first birth on the pace of subsequent fertility. These effects are particularly strong in the interval immediately following the first birth but persist even into the fourth interval. Important differences are found with respect to the experience of rapid fertility, rather than in the mean lengths of intervals. These results add to the growing attention to the social dimensions of age as a variable in fertility processes.

Adolescent↗

PubMed1976

Histologic specificity of the effect of age at birth of first child on breast cancer risk.

Slides of 531 breast cancers from Glamorgan, Wales, were classified according to the presence or absence of each of three histologic characteristics: stromal infiltration by linear strands of tumor cells, areas of intraductal carcinoma, and areas of lobular carcinoma in situ. The proportion of tumors with each of these characteristics was positively associated with age at first child-birth. Increasing age at first birth had a strong positive effect on the incidence risk of tumors with any of these features, but only a small effect on risk of tumors with none. For parous women, the rate of breast cancer with or without linear strands, with or without areas of intraductal cancer, and without areas of lobular carcinoma in situ was lower than for nulliparous women. Parity appeared not to reduce the risk of tumors with areas of lobular carcinoma in situ.

Adult↗

PubMed1978

Risk factors of breast cancer in Burma.

A hospital-based case-control study of breast cancer was undertaken in Rangoon. The age-standardized incidence rate, 25.1 per 100,000 woman-years and the shape of the age-incidence curve show that Rangoon women have an intermediate level of breast cancer risk compared to women of other countries in the world. The analysis is based on 193 cases and 400 controls. Breast cancer risk was found to be directly related to educational attainment. There was an increased risk associated with early menarche and late menopause. The most striking finding was the strong inverse relationship between risk and parity; women who had six or more children have only one-third the breast cancer risk of married women who had less than four children. This association is not confounded by case-control differences in age at birth of first child. The association of breast cancer risk with age at first birth was not striking; only women with a first birth after age 30 were at increased risk. Breast cancer risk was unrelated to lactation. Overall, the epidemiology of breast cancer in Burma is similar to that in most other countries. However, the possibility of an unusual relationship of risk to parity and age at first parturition warrants further exploration.

Adult↗

PubMed1979

The period between birth and first suckling in dairy calves.

The period between birth and first suckling was recorded for 82 dairy calves. 11 per cent of heifers' calves and 46 per cent of cows' calves had not suckled by 6 h after birth. All calves, whether suckling spontaneously or put to the teat at 6 hr, had adequate 48 h total serum immunoglobulin levels.

Animals↗

PubMed1975

Marital and reproductive experience in a community-wide epidemiological study of breast cancer.

The relationship of marital and reproductive experience to human breast cancer was studied using data collected during 1956-1962 by the Department of Biostatistics and Epidemiology at the Roswell Park Memorial Institute in Buffalo, New York. Information of epidemiological interest was obtained from all women with cancers of the reporductive organs in Buffalo, New York, and the adjoining township of Kenmore. For comparison, a probability sample of the same population was selected. During 1965-1967, an International Collaborative Study with similar objectives found a striking positive relationship between age at first birth and breast cancer risk. This finding can be interpreted as either indicating that an event associated with first birth at an early age protects against the development of breast cancer or that the hormonal status of a women both produces a delay in a woman becoming pregnant and increases the risk of developing breast cancer. The analysis of marital and reproductive histories in the Buffalo population study confirms previous reports of an increasing risk of breast cancer with increasing age at first birth. Attempts to distinguish the two interpretations mentioned by analyzing the interval between first marriage and time of birth in addition to age at first birth were not conclusive. This necessitated a similar analysis of data available in a larger series of 1164 breast cancer patients and 1200 non-neoplastic controls hospitalized at the Roswell Park Memorial Institute during 1957-1965. The results do not show an influence of interval between first marriage and first birth but do show an increased risk of breast cancer with increasing age at first birth. The results are thus consistent with a protective effect of an earyl age at first birth. These findings also have a bearing on recent suggestions that ovulatory failure predisposes to development of breast cancer.

Adult↗

PubMed1977

Labor force participation of working mothers and family formation: some further evidence.

This paper offers additional insight and evidence on the well-documented inverse relationship between female employment and fertility. Interviews with 388 working mothers from a probability sample in Robeson County, North Carolina, provide the data for testing the hypothesized relationships. Generally, the results indicate that lower fertility, lower desires and expectations, and earlier use of birth control are associated with work before the first birth and with employment of the longest duration. The timing of the first birth was not differentiated by variations in work experience. The results are conditional in that the relationships hold more for whites than for blacks or Indians.

Adolescent↗

PubMed1979

Breast cancer in black American women.

A case-control study of breast cancer among Black American women was conducted in seven hospitals in New York City from 1969 to 1975. Results are reported for 127 cases and 317 controls. Compared to women with a first birth before age 19, those with a first birth after 25 had a relative incidence rate for breast cancer of 3.8 and 2.2 for the pre- and postmenopausal age-groups, respectively. Compared to nulliparous women, parous women had a relative incidence rate of 0.6 for premenopausal and 0.7 for postmenopausal women. The incidence rate of breast cancer for women with a menopause after age 49 was estimated to be 3.1 times that of women with a menopause before age 45. Thus, the known risk factors for breast cancer among Whites are also related to the etiology of the disease among Blacks. The incidence rate of breast cancer has increased among younger Blacks since 1947 and is now similar to that among younger Whites. However, among older women, the incidence rate is still appreciably higher for Whites. The most likely explanation of this pattern is that Black women born since about 1925 are being exposed at the same frequency as White women to the causes of breast cancer.

Adolescent↗

PubMed1976

Quality of care given to first time birth control patients at a free clinic.

In an empirical study of the quality of care at a free clinic, criteria for optimal care for female first visits for birth control were established and 100 charts were reviewed, 50 in April 1974 and 50 in April 1975 with an interval in between of in-service training accompanied by new medical forms and procedures. An encouraging improvement in record keeping was observed. The authors feel it is important that free clinics concentrate on quality as well as quantity and accessibility of care.

Adult↗

PubMed1979

Labor supply behavior of prospective and new mothers.

Utilizing unique data generated from the National Longitudinal Surveys of Young Women, this paper examines the labor force participation of young mothers in the months immediately preceding and following the birth of the first child. Labor supply behavior at this point in the life cycle is described in greater detail than has hitherto been available. In addition, we analyze the independent effect of several factors of interest on the probability that a young woman will be in the labor force during various intervals surrounding the first birth.

Adolescent↗

PubMed1976

Labor force participation and family formation: a study of working mothers.

Drawing upon a sample of 638 mothers aged 18 to 40, with at least some marital work experience, significant associations were found between the extent, kind, and timing of employment and a series of family formation variables. Generally lower fertility, longer first birth intervals, and earlier use of birth control were associated with the longest work durations, the highest status jobs, and work before the birth of the first child. The data failed, however, to differentiate desired family size.

Adolescent↗

PubMedDate not supplied

A case-control study of breast cancer in Tianjin, China.

In a population-based case-control study of breast cancer in Tianjin, China, involving 300 cases and 300 population controls interviewed during 1985-1986, a number of strong risk factors were identified. Although average age at menarche was late by Western standards in this developing country (14.4 years), it was clearly related to risk. Women with their first menstrual period at age 12 years or earlier had 80% greater risk than women who started at age 17 years or later. Age at first full-term pregnancy was also strongly related to risk, with women whose first birth after age 30 years having 3.2 times the risk of women whose first birth was under age 20 years. Other established breast cancer risk factors in Western populations (family history of breast cancer, a history of benign breast disease, and use of oral contraceptives late in reproductive life) were also risk factors in this population. Parity and duration of lactation were both strongly protective against breast cancer development in univariate analyses. These two variables were highly correlated with each other and with age at first full-term pregnancy. Although the effects of each variable dissipated somewhat in multivariate analysis, our data strongly suggest that both parity and lactation independently contribute to breast cancer risk.

Adult↗

PubMed1975

A study of breast cancer in Irish women.

In a study of 100 women with breast cancer and 200 unaffected women the epidemiological characteristic of breast cancer most commonly described--namely, an excess of nonparous women among cases when compared with controls, was not observed. It is suggested that two factors, a dearth of first births born to mothers under 20 years of age and an unusually high proportion of first births when aged 30 years or more, are responsible for this finding. No association was found between breast cancer and socioeconomic status, marital status, age at marriage, age at first pregnancy, parity, or age at menarche. Significant associations with breast cancer included age at natural menopause, hysterectomy, and breast trauma. These findings are discussed.

Adult↗

PubMed1975

[A decrease in twin births and factors involved in multiple pregnancy].

The object of this investigation were the causes of the decrease of the frequency of twin births during the last two decades. In Moscow this frequency decreased from 1,19% in 1956 to 0,7% in 1973. Among the births the proportion of first births was observed to increase, as well as the proportion of very young mothers. The effect of this process on the women characterized by a tendency to polyembryony was more conspicuous, than in the average on the population as a whole. During the last decades the process of acceleration of puberty was observed both in the mothers of twins and in all the women in general. However a somewhat later onset of first menstruations is characteristic of the women having a tendency to polyembryony-Hormonal changes taking place in the course of acceleration are apparently one of the causes of the decrease of the twin births frequency.

Adolescent↗

PubMedDate not supplied

My first solo birth.

Explore the source record for details and available documents.

Female↗