Currently, the main application of childbirth simulation is to train medical professionals.35,36 To the knowledge of the authors, we offer a novel 3D simulation software tool to detect CPD and support clinical decisions on the optimal route of delivery. The use of such tools will reduce the numbers of unnecessary scheduled CSs, ECSs, and traumatic childbirths.
The STOL score generated by PREDIBIRTH is simple to use and helps classify patients into three delivery categories: favorable for a low-risk delivery (score of 1, 2 or 3); neutral requiring a physician to be in attendance and increased risk for instrumental delivery (score of 4, 5 or 6); and unfavorable that might be complicated by CPD or likely brain compression (score of 7 or 8), hence mandating a SCS as a possible alternative to vaginal delivery.
Many of the patients in the ECS group had CPD, which the PREDIBIRTH test can detect, thereby confirming that the smaller the pelvis, the more likely CPD is to be present. However, the PREDIBIRTH tests demonstrated that pelvis size is not the only criterion and that only by simulating the movement of the fetal head into the maternal pelvis using 3D simulation software is it possible to assess more accurately the risk level of childbirth.
The vast majority of traumatic deliveries in obstetrics are related to CPD, which can result in increased postpartum bleeding,37,38 urinary incontinence,39 fecal incontinence,40 pelvic prolapse,41 obstetric fistulas,42 risk to the infant’s brain, 43 and risk to the mother’s perineum.44 CPD can result in a negative and traumatic experience for families, with difficulty in the bonding between mother and child during the first hours of the newborn’s life. When an emergency occurs during labor that subsequently leads to an IVD or ECS, the delivery might be perceived as a failure, with significant trauma inflicted upon the mothers45 and their families.
ECS deliveries lead to morbidity and mortality rates up to 7 times higher than that associated with a CS scheduled prior to labor,46 demonstrating the critical need for the early classifying of patients prior to labor. The detection and prevention of CPD has the potential to optimize the organization of services and patient flow management.
Based on our analysis and considering the distribution of vaginal delivery failures in our population, the ECS rate would have been reduced by 30·8% (by 46·1% if we only consider rECS), the SCS rate would have increased by 43·7%, and the rate of inappropriately scheduled CSs would be reduced by 20·7%, had the STOL score recommendations been employed, without changing the total rate of CSs. Using STOL therefore enables obstetricians to better select the appropriate patients for SCS.
IVDs could not be definitively predicted, but the possibility of an IVD could be determined with the PREDIBIRTH test. IVDs in the upper inlet are no longer recommended in most countries.47 However, IVDs performed when the infant’s head is low enough can help to speed up the second phase of labor, thereby accelerating the birth to a greater degree than ECS. It is, therefore, not surprising that the IVD group had few unfavorable STOL scores.
For excessively long labors, in which the infant’s brain is at significant risk, forceps can help to protect the brain while extracting the infant more quickly during the second phase of labor.48 However, instrumental extractions are also associated with greater maternal perineal trauma.49
Future versions of the PREDIBIRTH software will include recent observations made on the maternal urogenital sinus changes during the second phase of labor with MRI50, and it will evaluate the levator ani stretching when the fetal head molding has been intense.
Over the past two decades of use, evidence supports that performing an MRI at 37 weeks of pregnancy results in less radiation exposure compared with X-rays and is safe for the mother and the fetus.51 Having no requirement for a contrast agent is also an asset when employing this technology, avoiding both the risk of maternal allergy and fetal teratogenicity.52
There are limitations to this study. It was a retrospective, population-based study of the radio pelvimetry indications requested by practitioners. Hence, this patient group had a bias towards a higher rate of significant CPD risk, which explains the high observed CS rate. It is therefore not representative of the general population of France, where the official national CS rate is approximately 21%, compared with the rate of 41·1% observed in the population studied in this work.
Inescapably, we do not know what the outcome would have been for the SCS group if SCS had not been performed. The STOL score provided useful information to determine whether women scheduled for CS, based solely on the criterion of pelvis size, might otherwise undergo a TOL to determine their actual need for such a procedure.
Prospective studies with a larger, more diverse populations, are therefore necessary to clarify the real impact of PREDIBIRTH as a decision support tool for the delivery management guidance after the 37th week of gestation.