Importance of optimal local uterine blood flow for implantation

The aim of this study was to determine whether uterine blood flow is an effective parameter to anticipate uterine receptivity.

The local uterine blood flow was measured in the endometrium and on the outside of the uterus in mice during the early stage of pregnancy and an implantation failure mouse model using transient and local suppression of signal transducer and activator of transcription-3 activity during implantation.

The local uterine blood flow was dramatically increased after mating and was decreased towards the time of implantation. The local uterine blood flow at 2.5 days post-coitus in signal transducer and activator of transcription-3 decoy transferred mice was significantly higher than in control mice. However, the range of individual values was too wide to find a cut-off point.

It is necessary to decrease local uterine blood flow after ovulation to prepare the opening implantation window. The optimal local uterine blood flow is regulated by time events during pregnancy. The range of individual values of uterine blood flow is wide using a laser Doppler blood flow meter. This parameter itself may not be an appropriate parameter to evaluate the prospect of uterine receptivity.