Birth defects and epidemiological factors in Tunisia.

Aim: To identify the birth defects listed in the embryo-fetopathology department of the maternity and neonatology center of Tunis (Tunisia), and to study the epidemiological factors.

Methods: We carried out a retrospective study on 2489 malformed cases including fetuses, stillborns and deceased newborns among 5750 ones autopsied in the embryo-fetopathology department of the maternity and neonatology center of Tunis.

Results: The sex ratio of autopsied cases was 1.06. 41% of them weighed less than 500 grams. The gestational age was between 22-28 weeks of amenorrhea in 41.3% of cases. Among the maternal characteristics, we noted an average maternal age of 30.1 years old (with extremes ranging from 16 to 51 years old), and a predominance of O blood group. Parental consanguinity and history of reproductive failure were found respectively in 37.4% and 32.5% of cases. Antenatal diagnosis was established in 62% of cases. It was positive in 59.5% of cases (all types of malformations combined). Among the 2489 malformed cases, 4568 birth defects were identified. Neurological anomalies were the most common (26.01%) followed by nephro-urological anomalies (13.16%) and cardiovascular anomalies (11.47%). During the study period, 164 cases of polymalformative syndromes were counted and 217 cases of chromosomal aberrations were classified.

Conclusion: This study allowed us to assess the frequency of birth defects, categorize them based on their type and determine the different epidemiological factors during a long period of nine years, even though our nation does not have a national register of birth defects. In Tunisia, it is important to carry out a national multicenter study in order to set a national register representing the real statistics of these anomalies.