Use of time to pregnancy in environmental epidemiology and surveillance
Mike Joffe1, Shantini Paranjothy, Hilary Fielder
1Department of Epidemiology and Public Health, Imperial College, St Mary's Campus, Norfolk Place, London W2 1PF, UK. m.joffe@imperial.ac.uk
Background:
Potential sources of environmental pollution, such as incinerators or landfill sites, can adversely affect reproduction and/or development. Time to pregnancy (TTP) is a validated measure of biological fertility that can be studied with relatively small populations.
Methods:
Pregnant local residents living within 3 km of a landfill site ('exposed' group, n = 200) or elsewhere in the Rhondda valleys ('unexposed' group, n = 400) were interviewed by health visitors or midwives. The response rate was 83%.
Results:
No difference was found in the TTP distributions between the exposed and unexposed groups. Relationships of TTP with covariates were consistent with the literature.
Conclusions:
In a context of public and scientific concern about possible reproductive toxicity, an interview study of TTP was highly acceptable to local women. A large enough sample to generate stable TTP distributions was readily achieved.
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