An earlier publication described the samples studied in 1995, 1998 and 2003 [1]. In principle, the surveys take place in the autumn to ensure some stability in the comparisons. Nonetheless, the last survey, which was initially planned for October GSK1349572 purchase 2009, was postponed until the spring of 2010 because of the A(H1N1) influenza pandemic. Data collection took place from 15 to 21 March 2010, or, in the largest units, from 15 to 28 March. The sample included 14681 women and 14903 children, including 440 twins and three triplets. The corresponding figures were 13147 women and 13318 children
in 1995, 13478 women and 13718 children in 1998, and 14482 women and 14737 children in 2003. Of 535 maternity units operating in metropolitan
France in 2010, one refused to participate, and another had no delivery during the study period. Interviews for 602 women either did not INCB024360 nmr take place or were incomplete because the mother refused to participate or was discharged before the investigator saw her, or because of a language problem or the mother’s or child’s health status. In the absence of an interview, the minimal information was obtained from the first health certificate, required by law to be filed within eight days after the birth. The analysis, performed with SAS software, compared the results for each of the four surveys for each indicator. We used Pearson’s Chi2 test to compare percentages and Student’s Isotretinoin t test to compare means. Trend tests were performed in cases where small but regular changes were observed between surveys. Because the large number of tests performed and the sample size create a risk of erroneously concluding that several indicators have significantly increased or decreased, we defined differences in the global comparisons as significant only if the p value was less than 1%. To make the tables clearer,
we have indicated that tests were not significant (NS) below this threshold. A threshold of 5% was used to define significance for the comparisons in population subgroups, because of their smaller size. Between 1995 and 2010, the mean maternal age increased continuously, from 28.6 to 29.7 years, that is, an increase of 26.4 (± 4.6) to 27.6 years (± 5.1) for nulliparas and from 30.1 (± 4.7) to 31.2 years (± 4.9) for multiparous women; this trend was significant between each survey for both groups ( Table 1). Finally, the proportion of women aged 35 year-old or older rose from 12.5% to 19.2%. Parity changed very little. The proportion of births to mothers living alone remained stable over the entire period, and the proportion of women of foreign nationality has increased since 1998. Educational level has risen very markedly; currently 51.8% of mothers have gone beyond high school, compared with 32.6% in 1995; the percentage of women who worked during pregnancy also increased.