First trimester placental markers in oocyte donation pregnancies

•Oocyte donation has a significant impact on blood placental markers' concentrations in the first trimester of pregnancy.•Oocyte donation pregnancies have higher free β-hCG levels compared to spontaneous pregnancies.•The biochemical differences observed could reflect alterations in the first stages of placentation.

IntroductionThis study investigates the hypothesis that placenta works differently in oocyte donation (OD) compared to spontaneous pregnancies. To verify this hypothesis we examine the first trimester maternal serum levels of free β-hCG and pregnancy-associated plasma protein-A (PAPP-A). Then we evaluated for potential differences of Down syndrome screening between OD pregnancies, in vitro fertilization/intracytoplasmic sperm injection pregnancies with autologous oocytes (IVF/ICSI) and spontaneous pregnancies.MethodsWe analyze 13624 spontaneously conceived pregnancies (Controls), 171 oocyte donation pregnancies (OD IVF/ICSI) and 76 IVF pregnancies with autologous oocytes (Autologous IVF/ICSI). Furthermore, we collect a cohort of 802 spontaneously conceived age-matched pregnancies, in order to evaluate how older uteri contribute to explain the changes in markers concentrations (Age-matched controls We compare the multiples of the median (MoM) of free β-hCG and PAPP-A and nuchal translucency.ResultsFree β-hCG levels are significantly higher both in OD IVF/ICSI pregnancies (1.44 ± 1.06 MoM) and Autologous IVF/ICSI (1.48 ± 1.02 MoM) compared to Controls (1.15 ± 0.84 MoM; p < 0.05) and Age-matched Controls (1.18 ± 0.98 MoM; p < 0.05). PAPP-A levels do not significantly differ among the four groups. Significantly lower nuchal translucency is detected in Controls (1.41 ± 0.36 mm) compared to OD IVF/ICSI (1.46 ± 0.44 mm; p < 0.05), in Autologous IVF/ICSI (1.51 ± 0.34 mm; p < 0.05) and Age-matched Controls (1.44 ± 0.42 mm; p < 0.05).DiscussionOocyte donation pregnancies (OD IVF/ICSI) are significantly related to altered maternal serum placenta marker levels. These alterations might be due to the IVF technique.