Results:
During the study period, there were 147563 patients. Of which, 1502 cases found to have major congenital anomalies, among them 947 (63.05 %) fetuses with isolated major anomalies and 555 cases (36.95%) with complex or multiple congenital anomalies. The average antenatal prevalence of congenital anomalies for 10 years was 10.1 per 1000 pregnancies. The mean gestational age during the first visit was 27(SD 5.5) weeks with range from 10 to 40 weeks. The mean (SD) of maternal age was 30 (6.0) years. Most (42.9%) referrals were from Muscat and 19.4% from AL Batinah (North) region. Coexisting maternal factors were observed in 481 (32%) of patients including gestational diabetes (8.8%), maternal age (6.59%) and recurrent early pregnancy loss (7.12%). Nervous system was the most common (29%) abnormalities observed and cardiothoracic system (24.9%) was the second most common. Perinatal outcomes showed that 9.6 % had early neonatal death, 19% had still births and 4 % had neonatal death. The perinatal mortality rate was 32.6% among fetuses with major congenital anomalies.
Conclusions: The prevalence of major congenital anomalies in our papulation is double the international figures. Early referrals can have a significant impact on early diagnosis, management and counselling. Modifiable maternal risk factors can be prevented and managed effectively during preconception period. This study emphasizes the need of national surveillance system and database for congenital anomalies and efforts should be focused in rising awareness of the occurrence and risk factors of congenital anomalies in Oman and the region of middle East.