Clinical Significance of Abnormal Results of Second Trimester Hormones in the Absence of Aneuploidy

Abnormal levels of hormones during second trimester of pregnancy may predict genetic disorders and complications of pregnancy.
This study was performed to evaluate the clinical significance of abnormal results in second trimester markers in the absence of aneuploidy.
This case-control study was conducted between May 2014 and December 2015 at the maternal fetal unit, Trakya University Faculty of Medicine in Turkey. Overall, 108 Turkısh pregnant females were included in this study. This research recruited patients (n = 46) with normal karyotype, who underwent prenatal invasive tests because of abnormal levels of second trimester hormones, along with a cohort of controls (n = 31) with hormonal results within normal ranges. For each patient, the researchers recorded the mode of delivery, gestational age at delivery, birth weight, complications, and adverse outcome of the pregnancy. Data were analyzed using Fisher’s exact tests and Yates contiunity correction tests for qualitative variables, and t- test and Mann-Whitney U test for quantitative variables.
Maternal age (mean ± SD) of the entire group was 31.77 ± 5.68 years (study group: 31.23 ± 4.39; controls: 32.13 ± 6.43, P > 0.05). Preterm delivery and preeclampsia was significantly higher in the study group (P = 0.02). In the study group, Alpha Fetoprotein (AFP) levels were significantly higher in patients with preeclampsia yet not in the controls. The AFP values under 0.77 multiple of the median in patients with elevated test results in the absence of aneuploidy appeared to be associated with the development of preeclampsia later in pregnancy.
Although the significance of higher AFP values have been discussed in the literature in terms of the development of adverse outcomes, the present study suggests that lower values must also be taken into account during patient follow-up.