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J C Ridley

Publications and source records attributed to J C Ridley.

7 recordsLinked to original sources
PubMed1990

High fertility of Old Colony Mennonites in Mexico.

Old Colony Mennonites in Mexico appear to demonstrate natural fertility, using no form of artificial birth control and apparently not attempting to limit family size. The resulting fertility is nearly as high as that of the Hutterites, although the Mennonites lack the communal economic system of the latter. Most Mennonites in Mexico migrated from Canada in the 1920s, and the largest single settlement, called the Manitoba Colony, is one of four in the state of Chihuahua. A 1967 partial census obtained data from 38% of the Mennonite households. Family size in the sample was close to that in a local survey taken in the same year. Available church records matched with census forms permitted verification of and corrections to 560 female reproductive histories. The median number of live births to women over age 45 years was 9.5, compared with 10.4 in the Hutterites. Age-specific marital fertility rates and birth intervals closely resembled those of the Hutterites.

Adolescent↗
PubMed1979

Recall and reliability of interview data from older women.

Retrospective fertility histories were collected from a purposive sample of 211 white, ever-married women, residing in four metropolitan areas of the USA and belonging to the birth cohorts of 1901-1910. At the time of interview, these women were aged 66 to 76. A random sample of 50 of the original respondents was reinterviewed by telephone on selected topics from the questionnaire. Responses to questions on dates and numbers of marriages, as well as births and other fertility events were coded to show whether the responses were exact, estimated by the respondent, or calculated by the editors. Respondents provided exact answers to an average of 90% of the questions they were asked. Reliability ratios, which were calculated for the above variables as well as ever-use of contraceptive methods, were comparable with those observed in previous studies of women in the childbearing years.

Aged↗
PubMedDate not supplied

Menarcheal age and subsequent patterns of family formation.

We examine whether age at menarche affects age at first marriage or first birth using two samples of U.S. women. Data are drawn from the Tremin Trust, a longitudinal study of menstrual cycles that recruited white women who were students at the University of Minnesota and from a survey of a nationally representative sample of white women born between 1900 and 1910. Regression models with cubic splines were used to analyze the relationship between age at menarche and age at first marriage. Cox proportional hazard models were used to examine the effect of age at menarche on the interval between marriage and first birth. Unlike earlier work, we found that once secular trends in both age at marriage and age at menarche were taken into account, there was no evidence that age at menarche affects either age at marriage or the timing of first births in these U.S. women.

Adolescent↗