In vitro fertilization is associated with placental accelerated villous maturation

Abstract

Objective: Accelerated placental maturation is regarded as a sign of vascular malperfusion and is often interpreted as a compensatory response by the placenta. In vitro embryo culture affects placental development. This study assessed placental maturation in spontaneous conceived and in vitro conceived pregnancies.

Methods: Retrospective cohort study on a single center between 2014 and 2017. For this study, preterm placentas of singleton pregnancies between 24 and 36 weeks were considered. Routine placental examinations were retrospectively reviewed.

Results: During the considered period, 423 placentas of singleton pregnancies were assessed. Three hundred ninety-six placentas were from spontaneous conception and 20 from in vitro fertilization and embryo transfer (IVF/ET). IVF/ET was significantly associated with accelerated villous maturation (AVM) and distal villous hypoplasia (DVH) (P<0.05).

Conclusions: Placental AVM and DVH were significantly associated with in vitro fertilization in singleton pregnancies. This result supports the hypothesis that AVM is a compensatory response by the placenta to improve its transport capacity in specific settings such as in vitro fertilization.

Keywords: Hypermaturation; accelerated villous maturation; distal villous hypoplasia; hypobranching; hyporamification; in vitro fertilization; placenta; placental maturation.

Figure 1

Placental villi stained by H&E. A. Mature intermediate villi at 27 weeks’ gestation (H&E, 100×). B. Terminal villi at 30 weeks’ gestation (accelerated villous maturation) (H&E, 100×). C. Non-branching/minimal branching villi at 34 weeks’ gestation (distal villous hypoplasia) (H&E, 40×). D. Mature intermediate villi and non-branching/minimal branching villi at 30 weeks’ gestation (accelerated villous maturation and distal villous hypoplasia) (H&E, 100×).