RT Journal Article
SR Electronic
T1 Is there an increased risk of twinning after discontinuation of the oral contraceptive pill?
JF Journal of Epidemiology and Community Health
JO J Epidemiol Community Health
FD BMJ Publishing Group Ltd
SP 275
OP 279
DO 10.1136/jech.43.3.275
VO 43
IS 3
A1 Murphy, M F
A1 Campbell, M J
A1 Bone, M
YR 1989
UL http://jech.bmj.com/content/43/3/275.abstract
AB We investigated whether conception soon after cessation of use of oral contraceptives affects the chance of bearing twins. Unpublished data from a large sample survey of contraceptive practice in Scotland were used to derive oral contraceptive discontinuation rates by month over the decade 1972-82 and these were related to estimated monozygotic and dizygotic twin birth rates and proportions by month in Scotland from 1974-82, using regression techniques. The results provide some support for the hypothesis that there is an increased risk of conceiving monozygotic twins within a year of ceasing to use oral contraceptives.