First trimester biochemical markers in twin pregnancies

Objective: Our aim was to investigate the first trimester serum markers and nuchal translucency (NT) measurements in twin pregnancies in our population. Materials and methods: We reviewed the results of all double tests that were performed in our hospital over a three-year period. Out of them, we selected all twins and compared them with a group of three times as many singleton controls. NT measurements and the first trimester serum markers from 49 twin pregnancies were compared to those of 147 pregnant women with normal singleton pregnancy. Results: There were no statistically significant differences in age, gestational age and maternal weight between the two groups (p>0.05). We found similar NT measurements in the two groups. The median MoM of Pregnancy-Associated Plasma Protein A (PAPP-A) and f beta-hCG levels in twins were statistically significantly higher than those in singleton pregnancies. Twelve percent of the twins (12.2 %) were the result of assisted reproduction technologies. IVF versus naturally conceived pregnancies showed similar MoM of PAPP-A (2.2 vs. 1.2, respectively) and f beta-hCG (Mann-Whitney U; p = 0.195 and p = 0.958). Conclusions: Our study revealed that median PAPP-A and f beta-hCG levels for twins were less than twice those of singleton values.