Contractions may not occur as of a result of uterine tumors. In addition, if the uterus is stretched, usually due to previous pregnancies or multiple gestation, contractions may be difficult. Irregular or weak contractions can be fixed through stimulation of the uterus or oxytocin infusions. Lack of contractions may be caused by an overwhelming amount of painkillers or anesthesia, by which the medications should be discontinued. In this case, it is appropriate for assisted vaginal delivery to be conducted. Cervical stenosis
Cervical dystocia, or stenosis, occurs when the cervix fails to dilate after a practical amount of time during positive uterine pains. The main problems in cervical dystocia is the lack of uterine inertia and cervical abnormalities, which prevent the cervix from fully dilating. It is very typical of patients that have hypopituitarism. There are many preexisting complications that may result in stenosis. Common conditions that lead to stenosis are tumors, a full bladder, large size of the infant, multiple pregnancies, delay in rupture of membranes, or problems with the cervix. High stress may interfere with the progression of pregnancy in cases such as these, leading to prolonged labor. Cephalopelvic disproportion
Cephalopelvic disproportion is the issue that arises when the fetus body or head is too large to pass through the woman’s pelvis. Common conditions that lead to CPD are diabetes, multiple pregnancies, small or abnormally shaped pelvis, atypical fetal positions, hereditary factors, and first time pregnancies. Medical professionals can usually estimate if fetal size is too large based on ultrasounds, but they are not always entirely accurate.
Ongoing trials
There are several ongoing studies testing the feasibility and efficacy of stem cell therapies for single ventricle diseases such as HLHS. These trials focus on what are the most effective stem cells, what is the best timing in the 3-stage repair, and what is the optimal delivery method. Phase IIb trial testing the efficacy of intramyocardial injections umbilical cord blood cells during Stage II (Glenn) repair. Phase I trial testing the efficacy of autologous cord blood cell infusion during Stage 1 (Norwood) repair within two-to-three days of birth. The ELPIS trial is a phase I/IIb open pilot testing the efficacy and safety of intramyocardial donor human mesenchymal stem cell injections in patients during Stage 2 (Glenn) and Stage 3 (Fontan) repairs. Phase I trial testing the efficacy of umbilical cord blood intramyocardial injections during Stage 2 (Glenn) repair. The PERSEUS study is a phase II trial testing the efficacy of intracoronary infusions of cardiac progenitor cells and evaluating function 3-months post-treatment. APOLLON study is a phase III clinical trial testing the efficacy and safety of intracoronary injections of autologous cardiac stem cells during Stage 2 (Glenn) or Stage 3 (Fontan) repair. CHILD Study is a phase I clinical trial testing the feasibility and safety of intramyocardial injections of c-kit+ cells during Stage 2 (Glenn) repair.It is important to keep in mind that patients with HLHS are at increased risk of developing heart failure as adults. It remains unknown if these potential therapies would reduce the future risk of heart failure in these patients.