Figure 4.

T2 dynamic imaging during maternal effort (successive images) at complete cervix dilation and unruptured membranes (dynamic acquisition). (A) Before maternal efforts: fetal head is above the sacro-pubic line. (B) Beginning of maternal efforts: the membranes start to change form to underline the vaginal route. (C) The intact membranes are approaching the superficial perineum level inside the vagina, the coccygeal bone is pushed posteriorly, the fetal head is under the superior limit of the pubic bone, and the bladder and the urinary sphincter are descending with the fetal head.