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Biomedical subjects

J Olsen

Publications and source records attributed to J Olsen.

At least 163 records · Page 9Linked to original sources
PubMed1999

Teratogenic evaluation of oxacillin.

Teratogenic studies of oxacillin in humans have not been published. The population-based data-set of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996 contains 22,865 foetuses or newborns with congenital abnormalities and 38,151 matched control newborns without congenital abnormalities. The mothers of 14 cases and 19 controls were treated with oral oxacillin during pregnancy. A teratogenic risk of oxacillin was not detected in this case-control study.

Abnormalities, Drug-Induced↗
PubMed1999

Induced abortion and duration of third stage labour in a subsequent pregnancy.

We set out to evaluate the impact of first trimester induced abortion on the duration of third stage labour and related complications in a subsequent pregnancy. The study was conducted in Shanghai city at 15 general hospitals (or maternity and infant health institutes) from November 1993 to March 1998. We identified all nulliparae who came for antenatal care within the first 63 days of pregnancy (2953); the women were divided into two cohorts according to their previous history of first trimester induced abortion. After enrollment, the women were interviewed five times from recruitment until 42 days after delivery. We included in the study all 1363 women who had a singleton vaginal live birth. Of these women, 703 were primigravida (non-exposed), 534 had had one previous first trimester induced abortion, and 126 women had had two or more first trimester induced abortions. The duration of third stage labour in minutes was longer in women with one or more previous induced abortions (mean=7.32 minutes) compared with primigravid women (mean=6.79 minutes). Prolonged third stage labour (>30 minutes) following one or more induced abortions was seen for 3.4% versus 1.0% in primigravid women. After adjusting for a number of potential confounders, women with one or more previous first trimester induced abortions had an odds ratio of prolonged third stage labour of 2.59 (95%C.I.=1.06-6.37) compared with primigravida, especially after an interpregnancy interval of more than 6 months (OR=3.24, 95%C.I.=1.29-8.13). The odds ratio of prolonged third stage labour was 3.14 (95%C.I.=1.22-8.09) if gestational age at the time of the induced abortion exceeded 49 days. Women with a first trimester induced abortion had no significantly increased risk of postpartum haemorrhage or retained placenta. It was concluded that a history of one or more first trimester induced abortions was related to an increased risk of prolonged third stage labour in the following pregnancy, particularly if the induced abortion was performed after 49 days of gestation.

Journal Article↗
PubMed1999

Male factors and socioeconomic indicators correlate with the risk of spontaneous abortion.

No less than 10% of clinically recognised pregnancies end as spontaneous abortions and the recurrence risk is high. Due to lack of data and appropriate study design only little is known about preventable causes of miscarriage. The aim of this study was to estimate the effect of paternal and environmental factors by studying reproductive histories in population based cohorts. We based the study upon two cohorts. The 'abortion cohort' consisted of 55 259 women who had a hospitalised spontaneous abortion in Denmark between 1980 and 1992 and who had a subsequent non-terminated pregnancy. The 'birth cohort'was based upon a 5% random sample of all women who in the same time period gave birth and subsequently had a non-terminated pregnancy (11 269 women). Data on change of partner, residence, mother's social status or occupation between the two pregnancies were linked to these two cohorts using the personal identification numbers and information stored in several population registers. Change of partner reduced the recurrence risk of spontaneous abortion substantially (OR = 0.59; 95 CI 0.52-0.67), but also changes in social status or job reduced the recurrence risk significantly. Changing the municipality of residence to a low risk area (based upon the geographical distribution of spontaneous abortions) reduced the risk of spontaneous abortion in both cohorts. A paternal effect on the recurrence risk of spontaneous abortion cannot be ruled out but environmental factors also play a role.

Journal Article↗
PubMed1999

Regional differences in waiting time to pregnancy: pregnancy-based surveys from Denmark, France, Germany, Italy and Sweden. The European Infertility and Subfecundity Study Group.

The objective of this study was examine geographical variation in couple fecundity in Europe. The study was based upon all recently pregnant (or still pregnant) women within well-defined geographical areas in Europe (Denmark, Germany, Italy, Sweden and France) at a given time period in 1992. Altogether, 4035 women responded to a highly structured questionnaire. Highest fecundity was found in Southern Italy and Northern Sweden; lowest fecundity was seen in data from the East German centre. Approximately 16% of the study population had a waiting time of more than 12 months to become pregnant. Most of the pregnancies were planned (64%) and approximately 14% were the result of contraceptive failures. The study shows that smoking, body mass index, age and parity did not explain the differences in fecundity found between the centres. Regional differences in fecundity exist and the causes may be genetic or due to variations in behavioural and environmental exposures.

Adult↗
PubMed1999

Low birthweight and prematurity in relation to paternal factors: a study of recurrence.

BACKGROUND: The importance of paternal determinants in the occurrence of low birthweight and prematurity is not well known. We investigated these outcomes in siblings and paternal half siblings as a function of changes in putative external determinants between two births in fathers who had experienced the birth of a premature and/or low birthweight (PTB/LBW) infant. METHODS: All fathers who, between 1980 and 1992, had an infant born before 37 completed weeks' gestation or weighing <2500 g and a following child were studied. We identified 14 147 pairs of siblings from Danish national registers. The recurrence risk was studied in three sub-cohorts defined by the outcome in the index child (PTB only, PTB/LBW, LBW only). We estimated the recurrence risk in the younger sibling according to changes of female partner, municipality type, occupation, and father's social status. RESULTS: The overall recurrence risk was 16.7% for preterm delivery and 16.8% for LBW. Changing female partner was, as expected, associated with a reduction in the recurrence risk for both outcomes (RR = 0.40; 95% CI: 0.27-0.60 for preterm delivery and RR = 0.38; 95% CI : 0.26-0.56 for LBW). None of the other studied factors was associated with changes in the recurrence risk. Fathers who changed partner had offspring with similar birthweight and gestational length between the three sub-cohorts, while a difference was evident in offspring to fathers whose female partner was unchanged. CONCLUSIONS: We did not identify any paternal factor of importance in the occurrence of LBW and preterm delivery.

Adult↗
PubMed1999

We should monitor human fecundity, but how? A suggestion for a new method that may also be used to identify determinants of low fecundity.

Human fecundity may be declining, and we may need ways to monitor it. The most simple monitoring is based on measuring waiting time to pregnancy retrospectively among pregnant women. Unfortunately, this design does not provide an estimate of fecundity, because infertile couples are excluded. We suggest a novel approach that combines the measurement of waiting time for pregnant women with information on the distribution of waiting time among women waiting to become pregnant. The method is based on principles from the case-cohort design.

Epidemiologic Methods↗
PubMed1999

Long-term follow-up of cognitive outcome after breech presentation at birth.

Studies of long-term consequences of birth in breech presentation are sparse. Therefore, we conducted a cohort study linking birth registry data with data collected during evaluation for military service in 4,298 conscripts born between 1973 and 1976. The cognitive functions were measured with the Boerge Prien IQ test. A total of 164 conscripts were born in breech presentation and 70 (42.7%) of these were delivered after Caesarean section. The mean Boerge Prien test score was 43.2 among men born in cephalic presentation and 39.9 among those born in breech presentation for a difference of 3.3 (95% confidence interval = 1.8-4.7). The negative association between breech presentation and cognitive outcome persisted after stratifying by Caesarean section and after adjustment for confounders. It also persisted when we restricted the analyses to term singleton pregnancies.

Adolescent↗
PubMed1999

Birth outcomes of women with celiac disease: a nationwide historical cohort study.

OBJECTIVE: We aimed to examine birthweight, low birthweight (<2500 g), and intrauterine growth retardation in offspring of women with celiac disease in relation to their first hospitalization for the disease. METHODS: This was a historical cohort study based on The Danish Medical Birth Registry data of celiac women discharged from Danish hospitals from 1977-1992. The study included 211 newborns to 127 mothers with celiac disease, and 1260 control deliveries. RESULTS: Before celiac women were first hospitalized the mean birthweight of their newborns was 238 g (95% confidence interval [95% CI] = 150, 325 g) lower than that of the control women, after adjustment for potential confounders. After the first hospitalization the mean birthweight for newborns of diseased women was higher than that of controls, by 67 g (95% CI = -88, 223 g) after adjustment for potential confounders. Before celiac women were first hospitalized we found an increased risk of low birthweight (odds ratio [OR] = 2.6, 95% CI = 1.3-5.5) and intrauterine growth retardation (OR = 3.4, 95% CI = 1.6-7.2). After celiac women were first hospitalized we found no increased risk of low birthweight and no babies with intrauterine growth retardation. CONCLUSIONS: Offspring of mothers with celiac disease had lower birthweight than expected and more than a three-fold higher risk of intrauterine growth retardation when birth occurred before the first hospitalization for the disease. After the mother's first hospitalization the birthweight was similar to controls and no increased risk of low birthweight was seen. Our study indicates that treatment of celiac women is important in the prevention of fetal growth retardation.

Adult↗
PubMed1999

Study of environmental, social, and paternal factors in preterm delivery using sibs and half sibs. A population-based study in Denmark.

OBJECTIVE: The aim of this study was to evaluate the influence on preterm delivery of changes in putative genetic and environmental risk factors between two consecutive births. Low social status is a suspected risk indicator of preterm delivery, but the impact of social mobility has not been studied before. PARTICIPANTS: The study uses national cohorts in which women act as their own controls. Subjects were identified by means of registries: 10,455 women who gave birth to a preterm child and had a subsequent live birth between 1980 and 1992 and 9849 women who gave birth to a child after 37 completed weeks of gestation and had a subsequent live born child in the same time period formed the cohorts. METHODS: The risk of having a premature infant in the subsequent pregnancy was analysed in each cohort as a function of changes in male partner, residency, occupation, and social status between the two pregnancies. RESULTS: There was a strong tendency to repeat a preterm delivery (18% v 6% in the general population). Social decline was associated with a moderate increase in the recurrence risk (OR: 1.22; 95% CI: 1.02, 1.47). In the reference cohort the risk of preterm delivery associated with changing from a rural to an urban municipality was 2.03 (95% CI: 1.14, 3.64). CONCLUSIONS: Social decline and moving to an urban municipality may be associated with preterm delivery.

Adolescent↗
PubMed1999

Socioeconomic and work related determinants of pregnancy outcome in southern Thailand.

STUDY OBJECTIVE: To examine the effect of socioeconomic status on pregnancy outcome in an urbanised area in a rapidly developing country. METHODS: A cohort of 1797 pregnant women who attended antenatal care clinics at the two 700 bed hospitals in Hatyai city was recruited from September 1994 to November 1995. The pregnant women were followed up from the 17th week of gestation until delivery. The socioeconomic indicators selected were family socioeconomic status, maternal education, maternal occupation, family income and work exposure characteristics based upon Karasek's job content questionnaires. Pregnancy outcomes were birth weight, low birth weight, small for gestational age and preterm delivery. MAIN RESULTS: Mean birth weight correlated with socioeconomic status and income but after adjustment for parity, maternal age and height, weight at delivery day, baby sex, obstetrical complications and antenatal care utilisation, only family income remained correlated with birth weight. No association with any socioeconomic status indicators was found when using dichotomous outcome (low birth weight, small for gestational age or preterm delivery). Only high psychological job demand was associated with small for gestational age. Confounder adjustment indicated that the observed social status differences in pregnancy outcomes were mainly attributable to mother's characteristics and antenatal service use. CONCLUSIONS: Socioeconomic indicators alone were not associated with reduced fetal growth or preterm delivery in this study, which recruited mainly lower or middle class women. Karasek's psychological job demand was only weakly correlated with small for gestational age infant.

Adolescent↗
PubMed1999

Design options and sources of bias in time-to-pregnancy studies.

Studies of fecundity are few, and there is a need to know how fecundity develops over time and to identify its determinants. Since fecundity is best measured by studying time to pregnancy, valid and well-recognized instruments are needed for data collection. A standardized questionnaire on fecundity not only has to obtain information on waiting time, but also information on the importance of evaluation results. The use of contraceptive methods, the understanding of family planning, and behavioral changes driven by past reproductive experience are issues of importance for designing and interpreting results, as are other sources of bias also.

Bias↗
PubMed1999

Comparison of in vitro tests for evaluation of passive transfer of immunoglobulins in giraffe (Giraffa camelopardalis).

Serum samples from captive giraffe (Giraffa camelopardalis) were tested to assess passive transfer of immunoglobulins using in vitro methods developed for domestic ruminants. Estimated immunoglobulin levels were compared using five tests (protein electrophoresis, total protein refractometry, zinc sulfate turbidity, glutaraldehyde coagulation, and sodium sulfite turbidity). A linear relationship was observed among total protein, gamma globulin (electrophoretic measurement), and immunoglobulin level based on spectrophotometric measurement of zinc sulfate turbidity. Nonquantitative assays also demonstrated statistical correlation with the quantitative methods. Using criteria similar to those established for domestic species, cutoff values for failure of passive transfer (FPT) were established for these tests in neonatal giraffe: 1) total protein <6.0 g/dl; 2) gamma globulin < 0.5 g/dl; 3) estimated immunoglobulin level < 1,000 mg/dl (zinc sulfate turbidity); 4) glutaraldehyde coagulation test negative; or 5) no visually detectable turbidity in 16% sodium sulfite or Bova-S negative. Retrospective examination of the medical histories showed a strong statistical association between animals designated as having FPT and those that were removed from their dams based on clinical assessment to be hand-reared. Application of these tests in the field should allow earlier detection and intervention for FPT in neonatal giraffe.

Animals↗
PubMed1999

The Danish in vitro fertilisation (IVF) register.

The Danish IVF Register was established in 1994 and covers all treatments with in vitro fertilisation (IVF), intracytoplasmatic sperm injection (ICSI), frozen embryo replacements (FER) and egg donations (ED). Since data are recorded with personal identification numbers, they provide the starting point for cohort studies of treated women and offspring. It is obligatory for each clinic to report each treatment cycle to the register, by means of special treatment report forms that contain clinical as well as laboratory data. The pregnancy outcome is reported on special forms no later than two months after birth. The personal identification number (CPR) allows cross-linkage of the data from the register, with several other national Danish registers, such as the National Hospital Register the Abortion Register, the Danish Register of Causes of Death, the Cytogenetic Central Register and the Cancer Register. In 1998 a total of 7131 IVF and ICSI cycles were performed in Denmark. This corresponds to around 6500 cycles per 1 million women in the reproductive age, which is among the highest number per capita in the world. The coverage of the register is believed to be very close to 100% for the treatment reports, but less for the pregnancy outcome forms, at least during the first two years after the register was established. The main importance of the register is quality control aspects of assisted reproductive techniques and research in relation to follow-up on maternal and infant health.

Adolescent↗
PubMed1998

The laminins: role in intestinal morphogenesis and differentiation.

Dynamic and reciprocal heterotypic cell interactions are crucial for intestinal morphogenesis and differentiation. This paper emphasizes the role of basement membrane molecules and in particular of laminins as potent mediators in this intercellular cross talk. Changes in the expression or localization of laminin isoforms or of integrins during development and cell migration strengthen the concept that heterogeneity in cell-matrix interactions could mediate distinct cell responses. A combination of genetic or biochemical approaches associated with in vitro models allows us to study the potential role of each laminin isoform in basement membrane assembly, cell migration, or cell differentiation.

Animals↗
PubMed1998

Adult and prenatal exposures to tobacco smoke as risk indicators of fertility among 430 Danish couples.

During 1992-1995, 430 Danish couples were recruited after a nationwide mailing of a letter to 52,255 trade union members who were 20-35 years old, lived with a partner, and had no children. The couples were enrolled into the study when they discontinued birth control, and they were followed for six menstrual cycles or until a clinically recognized pregnancy. At enrollment and each month throughout the follow-up, both partners completed a questionnaire that asked them about their smoking, alcohol consumption, and intake of caffeinated beverages. The effect of current smoking and smoking exposure in utero was evaluated by using a logistic regression model with pregnancy outcome of each cycle in a Cox discrete model calculating the fecundability odds ratio. After adjustment for female body mass index and alcohol intake, diseases in female reproductive organs, semen quality, and duration of menstrual cycle, the fecundability odds ratio for smoking women exposed in utero was 0.53 (95% confidence interval (CI) 0.31-0.91) compared with unexposed nonsmokers. Fecundability odds ratio for nonsmoking women exposed in utero was 0.70 (95% CI 0.48-1.03) and that for female smokers not exposed in utero was 0.67 (95% CI 0.42-1.06). Exposure in utero was also associated with a decreased fecundability odds ratio in males (0.68, 95% CI 0.48-0.97), whereas present smoking did not reduce fecundability significantly. It seems advisable to encourage smoking cessation prior to the attempt to conceive as well as during pregnancy.

Adolescent↗