Risiko for spontanabort blant norske, førstegangsfødende tannleger

Abstract

SAMMENDRAG

Det er usikkerhet om eksponering for stoffer fra tannfyllingsmaterialer kan påvirke kvinners fertilitet. Vi har

undersøkt forekomst av og risiko for spontanabort i første svangerskap blant praktiserende tannleger og sammenlignet

resultatene med yrkesaktive lektorer/adjunkter og hjemmeværende kvinner. Et spørreskjema som omfattet

en reproduktiv og en yrkesrelatert historie, ble sendt til alle kvinnelige medlemmer av Den norske tannlegeforening

og et tilfeldig trukket utvalg av kvinnelige medlemmer i Norsk undervisningsforbund. Ved at ikke alle

kvinnene var yrkesaktive i tiden før de ble gravide, kunne studiepopulasjonen deles i praktiserende tannleger

(n=727), yrkesaktive lektorer/adjunkter (n=340) og hjemmeværende (n=300).

For studiepopulasjonen samlet spontanaborterte ca. ni prosent av alle kvinner i første svangerskap, og over

tiårsintervallene fra 1951 til 1990 økte spontanabortfrekvensen fra 5,3% til 11,5%. Det var en signifikant sammenheng

mellom graviditetsutfall og tid til graviditet. Kvinner som hadde brukt ni måneder eller mer på å bli gravide,

spontanaborterte to ganger hyppigere enn dem som brukte kortere tid.

Risikoen for spontanabort blant praktiserende tannleger totalt var den samme som for hjemmeværende og for

undervisningspersonell. I aldersgruppen over 30 år hadde tannlegene imidlertid 2,4 ganger høyere odds ratio (95%

konfidensintervall: 1.0–5.4) enn undervisningspersonell. Antatt eksponering for kvikksølv fra innlegging av amalgamfyllinger,

for bensenholdig desinfeksjonssprit og for andre løsemidler økte ikke risikoen.

Dahl JE, Sundby J.

Risk for spontaneous abortion among primiparous dental surgeons in Norway.

Nor J Epidemiol

Occupational exposure to potentially hazardous agents may increase the risk of spontaneous abortion. The present

study addresses the frequency and risk for miscarriage among dental surgeons compared to those of high-school

teachers and non-employed women. A self-administered postal questionnaire was mailed to all dental surgeons

registered in the Norwegian Dental Association (n=1320), and to a random sample of high schools teachers

(n=1084), recruited from the registry in the Norwegian Educational Association. The data were collected retrospectively

comprising the reproductive and occupational history of the female. The occupational exposure was

addressed by a thorough examination of the work performed in the time when the couple tried to conceive and the

woman became pregnant for her first time. The use of mercury containing dental amalgam, chloroform based root

canal sealer, ethanol based disinfectant containing benzene, and other organic solvents was addressed in detail.

Nitrous oxide sedation had not been used in dental surgeries in Norway when the survey was undertaken. The

study was approved by the National Committee for Research Ethics and the Data Inspectorate in Norway.

As not all women were working at the time when they became pregnant, the study population was subdivided

into dental surgeons (n=727), high-school teachers (n=340) and group of homemaking women (n=300). On the

average, 9.2% of the primiparous women had a spontaneous abortion. In the time period 1951-1990, the incidence

of miscarriage increased from 5.3% to 11.5% for the study population. There was a significant correlation between

outcome of pregnancy and time to pregnancy. Spontaneous abortion occurred twice as often in women who

had a waiting time to pregnancy of nine months or more compared to women having shorter waiting time.

The risk for spontaneous abortion among practising dentists in total was the same as for homemakers and

teachers. In the age group past 30 years the dentists had a 2.4 times higher odds ratio (95% confidence interval:

1.0–5.4) than teachers but it was not possible to link this to a specific occupational exposure. Exposure to mercury

from the use of dental amalgam, to ethanol based disinfectant containing 0.25% benzene or to other solvents did

not increase the risk.

ENGLISH SUMMARY1999; 9 (1): 51-55.