Time to pregnancy among women occupationally exposed to lead.
A retrospective time-to-pregnancy study was conducted among women biologically monitored for exposure to lead. The women were participants of a previous study on spontaneous abortion. They were classified into exposure categories on the basis of questionnaire information, and individual blood lead (B-Pb) measurements. The adjusted incidence density ratios (IDR) of clinically recognized pregnancies were .93 (95% confidence interval [CI] .56 to 1.57) for very low (B-Pb < .5 mumol/L), .84 (CI .48 to 1.45) for low (B-Pb .5 to .9 mumol/L), and .80 (CI 0.42 to 1.54) for higher (B-Pb > or = 1.0 mumol/L) exposure compared with no exposure, in the discrete proportional hazards analysis. Exposure to inorganic lead was not associated with fecundability at current, low-exposure levels. The suggestive finding among the eight most heavily exposed women (B-Pb 1.4 to 2.4 mumol/L, IDR .53; CI .19 to 1.52) should be confirmed or refuted in a larger study.
Finnish Institute of Occupational Health, Helsinki, Finland.
M
M
Sallmén
A
A
Anttila
M L
ML
Lindbohm
P
P
Kyyrönen
H
H
Taskinen
K
K
Hemminki
D000022:Abortion, Spontaneous / Q000209:etiology; D005260:Female; D006801:Humans; D015994:Incidence; D007247:Infertility, Female / Q000139:chemically induced*; D007854:Lead / Q000009:adverse effects*; D008597:Menstrual Cycle / Q000502:physiology; D016273:Occupational Exposure / Q000009:adverse effects*; D011247:Pregnancy; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D013997:Time Factors
D007854:Lead