RESUMEN
Objective · To evaluate the association between the abnormal maternal serum markers of alpha fetoprotein (AFP), human chorionic gonadotrophin (hCG) and unconjugated estriol (uE3) in the second trimester screening and the adverse obstetric outcomes other than trisomy 21 (T21),trisomy 18 (T18) and open neural tube defects (ONTD), and to provide local data for supporting evidence based clinical managements. Methods · A retrospective cohort study was performed in the women who received second trimester maternal serum screening in the International Peace Maternal and Child Health Hospital between 2012 and 2014, with naturally conceived singleton pregnancies. Obstetric outcomes were followed up by searching electronic medical records within the hospital. Abnormal level of marker was defined as a MOM value ≥ 99th (P99) or ≤ 1st percentile (P1) of the overall screened population. Incidence of an adverse obstetric outcome was compared between the groups with abnormal markers and the control with all markers in normal. Results · ① A total of 25616 pregnancies were included in this study, in which 4526 were identified as having various adverse obstetric outcomes. Among them 4143 pregnancies were with isolated and 383 pregnancies were with co-occurring two or more adverse outcomes. ② When compared to pregnancies with normal levels of all three serum markers, pregnancies with decreased AFP or decreased hCG did not show associations with any adverse obstetric outcomes. However, pregnancies with increased AFP, increased hCG or decreased uE3 were at increased risk for a variety of abnormal pregnancy outcome. In 18 pregnancies with an outcome of fetal chromosomal abnormalities other than T21 and T18, 9 presented with either increased AFP, increased hCG or decreased uE3, with relative risk ratios of 13.33、35.00 and 59.00, respectively. ③ The performance of those markers tended to be improved in a subset of adverse obstetric outcomes, including low birth weight