Trends in orofacial cleft prevalence and the effect of prenatal detection on pregnancy outcomes in Northern Netherlands.

OBJECTIVES

To describe trends in total and live birth (LB) prevalence of orofacial clefts (OFCs) and investigate the effect of prenatal diagnosis on its LB prevalence in the Northern Netherlands (NNL) over a 21-year period.

STUDY

DESIGN

Cases with OFCs were selected from Eurocat NNL, a population-based registry of congenital anomalies. Aggregated denominator data (controls) was derived from Statistics Netherlands. We categorized OFCs into cleft lip with or without palate (CL±P) and cleft palate (CP). We analyzed trends in prevalence and temporal patterns in prenatal detection rates and birth type by calculating the annual percentage change (APC) using Joinpoint regression or the X² test for linear trends.

RESULTS

The total prevalence of CL±P decreased non-significantly from 1.65/1000 births in 2001 to 1.17/1000 births in 2021 (APC=-0.82 [95 %CI: -2.18, 0.55]), whereas the LB prevalence decreased significantly from 1.57/1000 births in 2001 to 0.93/1000 births in 2021 (APC=-1.65 [95 %CI -3.03, -0.25]). The total and LB prevalence of CP did not show significant decreasing trends. The prenatal detection rate of CL±P increased from 15 % to 71 % between 2001 and 2007 (APC=34.38 [95 %CI 24.27, 52.26]), followed by a slower increase, reaching 94 % in 2021 (APC=3.57 [95 %CI 0.59, 6.08]). The percentage of induced abortions increased from 3.2 % to 12.7 % between 2001 and 2021 (X2 for trend P < 0.001), with most induced abortions occurring in the CL±P associated with genetic/syndromic or other congenital anomalies.

CONCLUSIONS

The LB prevalence of CL±P decreased, which may be associated with better prenatal detection and increasing pregnancy terminations due to unfavorable prognosis.