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Biomedical subjects

S E Buitendijk

Publications and source records attributed to S E Buitendijk.

29 records · Page 2Linked to original sources
PubMed1995

[Frequency and determinants of episiotomy in second-line obstetrics in The Netherlands].

OBJECTIVE: To study factors that influence the probability of episiotomy in Dutch gynaecologist-supervised deliveries. SETTING: Obstetric units of Dutch hospitals. DESIGN: Observational study. METHODS: Data of 65,313 gynaecologist-supervised, vaginal deliveries of live-born singletons registered in the Dutch National Obstetric Database of 1990, were used. Firstly, the effect of characteristics of the mother, the child, the pregnancy, and the delivery on the probability of episiotomy were assessed in univariate analyses. Subsequently logistic regression analysis was used to determine the effect of each variable, while adjusting for the other variables. RESULTS: The episiotomy rate in the total group of gynaecologist supervised deliveries was 39%. In the subgroup of vaginal deliveries of live born singletons, the rate was 46%. Besides the well-known risk factors such as parity, instrumental delivery and length of second stage of labour, ethnicity was also found to have an independent effect on the risk of an episiotomy. Mediterranean, Creole and Hindu women had a lower episiotomy risk than Dutch women (OR: 0.47 and 95% CI: 0.44-0.51). Gynaecologists more often performed episiotomy than midwives, after adjusting for possible confounding factors (OR: 1.54; 1.46-1.63). In University hospitals fewer episiotomies were performed than in large non-university hospitals (OR: 0.81; 0.76-0.87. CONCLUSION: The decision to perform episiotomy appears not to depend solely on factors related to perineal rupture or foetal complications. The probability of episiotomy is also influenced by attendant at delivery and type of hospital.

Academic Medical Centers↗
PubMed1994

Differential misclassification of alcohol and cigarette consumption by pregnancy outcome.

BACKGROUND: The validity of the results of studies using retrospectively collected information on exposures is often criticized, because cases may report differently from controls even if their true exposure status is the same. This study was performed to quantify the extent to which this effect (differential misclassification) may occur for alcohol and cigarette consumption by pregnancy outcome. METHODS: Prospective as well as retrospective information on alcohol and cigarette consumption was collected for 2806 mothers resident in all 12 provinces of the Netherlands, who gave birth between 1978 and 1979. Changes in mean reported consumption and changes from user to non-user based on retrospective and prospective information were compared for cases and controls. This was done by calculating absolute differences (retrospective minus prospective) in reported consumption and by calculating 'misclassification odds ratios'. Further, conventional odds ratios based on retrospective information were compared with those based on prospective information. Outcome measures were stillbirth, small for gestational age (SGA), congenital malformations, preterm birth and low birthweight. RESULTS: The only statistically significant result was found for smoking and SGA. Mothers with an SGA child retrospectively reported a higher number of cigarettes smoked than they had prospectively, more so than mothers of a control child. However, the odds ratios of the relation between SGA and smoking based on prospective and retrospective information, respectively, were virtually the same. CONCLUSIONS: Our results suggest that information bias is unlikely to have a large influence on effect estimates in studies using retrospective information on alcohol and cigarette consumption.

Adult↗
PubMed1994

Episiotomies and the occurrence of severe perineal lacerations.

OBJECTIVE: To investigate the relation between the use of mediolateral episiotomy and the occurrence of severe (third degree) perineal tears in hospital deliveries in the Netherlands. DESIGN: An observational study. SUBJECTS: Data were derived from the Dutch National Obstetric Database (LVR) of 1990, from which 43,309 spontaneous, occipito-anterior, vaginal deliveries of live, singleton infants were investigated. INTERVENTION: Medio-lateral episiotomy. MAIN OUTCOME MEASURE: The occurrence of severe perineal tears. RESULTS: The severe tear rate was 1.4% in the total study group. Using multiple logistic regression to control for possible confounding variables, the use of mediolateral episiotomy was found to be associated with a more than fourfold decrease in risk of severe lacerations (odds ratio 0.22, 95% CI 0.17 to 0.29). Further, in a logistic model deliveries in hospitals with restrictive use of episiotomy (< 11%) were compared with those in hospitals with liberal use of episiotomy (> 50%). Liberal use of episiotomy was not associated with a lower frequency of severe perineal tears. CONCLUSION: Although a protective effect of mediolateral episiotomy on the occurrence of severe lacerations was found, liberal use of mediolateral episiotomy should be discouraged on the basis of our findings.

Episiotomy↗
PubMed1993

[Obstetrical outcome in teenage pregnancies in The Netherlands].

OBJECTIVE: To compare the course of teenage pregnancies and deliveries with that in women between the ages of 20 and 29. DESIGN: Observational. SETTING: The Netherlands. METHOD: Using data from the 1989 National Obstetric Database (LVR), 4500 teenage pregnancies were studied, to compare the risk of preterm birth, low birth weight and delivering a small for gestational age (SGA) baby between teenagers and older women. RESULTS: Women between the ages of 13 and 19 ran one and a half times as high a risk of having a preterm baby as women between the ages of 20 and 29 years (p < 0.0001). The risk of intrauterine death was 4 times as high for age 13-17 and 2 times as high for age 18-19 compared with older women (p < 0.0001). These results were found for teenage mothers of Dutch origin as well as for young mothers of foreign descent. Deliveries by teenagers were more often spontaneous, were of shorter duration and less often needed assistance than deliveries in older mothers (p < 0.001). CONCLUSION: Even in the Netherlands, with the lowest teenage pregnancy rate in the Western world and a prenatal care system generally considered of high quality, teenage pregnancies have less favourable outcomes than those in older women. Since we had no information on cultural background, socioeconomic status or life style, further research into determinants of outcomes of Dutch teenage pregnancies is indicated.

Adolescent↗
PubMed1993

Congenital hypothyroidism screening and the cutoff for thyrotropin measurement: recommendations from The Netherlands.

OBJECTIVES: There is little agreement as to the optimal cutoff point for thyrotropin testing in primary thyroxine screening programs for congenital hypothyroidism. Most programs in the United States use a cutoff point of 10% of the lowest thyroxine values, whereas in the Netherlands a cutoff point of 20% is used. Therefore, the results of the Dutch program may provide valuable information about the optimal cutoff point. METHODS: The frequency distribution of screening thyroxine values was studied in all cases of permanent primary congenital hypothyroidism (n = 481) detected in 1,601,603 screened children born during the period from January 1, 1981, to December 31, 1989, in the Netherlands. RESULTS: Programs using a 10% cutoff point would have missed 1.5% of cases. Above the 10% cutoff point, the marginal costs increase quite rapidly because of the escalating numbers of thyrotropin measurements necessary to detect one case of permanent primary congenital hypothyroidism: 20,000 in the range of 11% to 15% and 40,000 in the range of 16% to 20%. CONCLUSIONS: Based on these findings, a cutoff point of at least 10% is recommended.

Congenital Hypothyroidism↗
PubMed1992

Non-differential underestimation may cause a threshold effect of exposure to appear as a dose-response relationship.

It is generally believed that non-differential misclassification will lead to a bias toward the null-value. However, using one graphical and one numerical example, we show that in situations where underestimation more than overestimation is the problem, non-differential misclassification may lead to a bias away from the null-value for intermediate categories of exposure variables. We show that a true threshold level for an exposure may, subsequently, appear as a dose-response relationship. Underestimation more than overestimation is likely to occur in studies in which self-reports are used to obtain data on activities which respondents voluntarily engage in and which are socially not acceptable or known to be potentially dangerous. Researchers should be aware that both a shown deleterious effect at a low level of exposure and a dose-response relationship may in fact be spurious and due to underestimation of exposure at higher levels.

Bias↗