Objective: To investigate the association between pregnancy planning and orofacial clefts in the United Kingdom.Design: Case–control study.
Setting: Scotland and the Manchester and Merseyside regions of England.
Participants: One hundred and ninety-one children born with nonsyndromic orofacial cleft, 1997 to 2000, and 247 controls.
Main outcome measure: Cleft lip with and without cleft palate, and cleft palate.
Results: There was an inverse association between planning for pregnancy and orofacial cleft in the offspring (odds ratio [OR] = 0.51, 95% confidence interval [CI] = 0.33–0.79). An unplanned pregnancy together with smoking in the first trimester of pregnancy resulted in almost treble the risk of a child with an orofacial cleft when compared with those who planned their pregnancy and did not smoke (OR = 2.92, CI = 1.50–5.65).
Conclusions: Planned pregnancies were associated with a lower risk of orofacial clefts. Isolation of the elements of pregnancy planning implicated in these results is difficult. Current preconception advice needs to reach a wider audience; however, for maximum impact, efforts are needed to reduce the numbers of unplanned pregnancies.
