PT  - JOURNAL ARTICLE
AU  - Murphy, M F
AU  - Campbell, M J
AU  - Bone, M
TI  - Is there an increased risk of twinning after discontinuation of the oral contraceptive pill?
AID  - 10.1136/jech.43.3.275
DP  - 1989 Sep 01
TA  - Journal of Epidemiology and Community Health
PG  - 275--279
VI  - 43
IP  - 3
4099  - http://jech.bmj.com/content/43/3/275.short
4100  - http://jech.bmj.com/content/43/3/275.full
SO  - J Epidemiol Community Health1989 Sep 01; 43
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 Unpublished data from a large sample survey of contraceptive practice in Scotland were used to derive oral contraceptive discontinuation rates by month over the decade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.