Purpose: to compare the outcome of pregnancies with and without threatened abortion presenting alive embryo/fetus between 6 and 13 weeks at sonographic evaluation. Method: this was a retrospective case-control study, carried out from February 1998 to December 1999. Criteria for inclusion were: topic and single pregnancy; embryo/fetus cardiac activity present in the ultrasound scan; gestational age between 6 weeks and 13 weeks and 6 days, absence of fetal anomalies, absence of attempt of abortion by drugs or manipulation, absence of maternal disease, known pregnancy result. A total of 1531 pregnancies were examined, of which 258 with threatened abortion (case group) and 1273 without threatened abortion (control group). The two groups were compared regarding outcome such as: abortion, stillbirth, prematurity and intrauterine growth restriction. Results: the percentage of abortion (11,7%) and prematurity (17,8%) were higher in the group with threatened abortion (p<0.001 and p=0.026, respectively). The frequency of stillbirth and intrauterine growth restriction did not differ significantly between the groups.Conclusion: threatened abortion with alive embryo/fetus in 6- to 13- week gestation presented a higher abortion risk and subsequent prematurity.
Threatened abortion; Ultrasonography; Prematurity; Intrauterine growth restriction
