Abstract:
:The risks of conception, due to sexual intercourse at various times before and after the periovulatory rise in the woman's basal body temperature, are evaluated. In general, the risk is small nine or more days before, and two or more days after, the first day of elevated temperature. The model for the conception probabilities assumes exponential survival distributions for sperm and egg and a specific probability that an egg is viable. Median survival times for sperm and egg are estimated at 1.0 days and 0.5 days, respectively. The Pearl indices for intercourse on the third and fourth day of elevated temperatures are 4.7 and 1.2 pregnancies per 100 woman-years, respectively.
journal_name
Biometricsjournal_title
Biometricsauthors
Royston JPsubject
Has Abstractpub_date
1982-06-01 00:00:00pages
397-406issue
2eissn
0006-341Xissn
1541-0420journal_volume
38pub_type
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