A four-year retrospective study of amniocentesis: one centre experience

Monitor the performance of the amniocentesis procedure for prenatal diagnosis and particularly the acquisition of results (time to get, success in getting them).

This is a retrospective review of case notes of all pregnant women undergone amniocentesis in our department during the period 2002-2005. Two main operators performed the procedure, using 22 gauze needle usually and 20 gauze should longer needle was needed. Sevendy three patients undergone amniocentesis. The reasons for having this procedure were: increased risk for Down syndrome in 68% (50/73), maternal request in 24% (18/73), suspicious ultrasound findings in 4% (3/73) and family history in 3% (2/73). Maternal age ranged from 20 to 45 years and the gestation time that amniocentesis was performed was 15 to 23 weeks. Fluorescence in situ hybridization (FISH) and culture were used in order to obtain karyotype results.

In 92% (67/73) of cases one needle pass was needed. FISH and culture were performed in 96% (70/73) of cases, FISH only in 3% (2/73) and culture only in 1% (1/73). The chromosome results were normal in 93% (68/73) of cases, Down's syndrome in 4% (3/73) and Edwards syndrome in 3% (2/73). The outcome of pregnancies was: live births in 89% (65/73), stillbirths at 32 weeks and 35 weeks in 3% (2/73), miscarriages in 1% (1/73 at 19 weeks, 3 weeks after the amniocentesis), terminations in 7% (5/73, due to chromosomal abnormalities). Sixty one women delivered at term (84%) and 6 women (8%) delivered preterm.

The post amniocentesis rate of miscarriage is calculated at 1% in our centre. FISH analysis can relieve stress of couples by reducing the waiting time for results.