Obese, Oxytocin, Primiparous Women
Conditions
Keywords
Obese, Primiparous women, Oxytocin
Brief summary
The rate of caesarean section is higher among obese pregnant women, leading to increased morbidity in this already vulnerable population. Oxytocin is the main drug used in obstetrics to optimize progress of labour, but observational studies have suggested that its efficiency may be insufficient in obese women with usual doses. We design a randomised controlled trial to test the effect of an increased oxytocin dose on the rate of caesarean section in obese primiparous women with spontaneous or induced labour.
Detailed description
The hypothesis underlying this trial is that an increase in oxytocin dose can reduce the rate of caesarean sections in primiparous obese patients, with a spontaneous or induced onset of labour, without increasing maternal or neonatal morbidity. This would be a major step forward in reducing morbidity in an at-risk population and in improving the obstetric prognosis for future pregnancies. The research is a double-blind controlled trial, including primiparous obese women in spontaneous or induced labour, for whom a prescription of oxytocin is decided. Oxytocin is currently indicated for notably insufficiency of uterine contractions, at the beginning or during labour.The recommended dosage in the market authorization will be used for the control group. The control group will receive oxytocin at 2 milli-International unit /mL and the intervention group at 4 milli-International unit /mL, controlled by pump (final volume = 500 mL) or electrical syringe (final volume = 50 mL). The primary objective is to compare the effect of higher doses of oxytocin (intervention group) vs standard doses of oxytocin (control group) on the rate of caesarean sections in obese patients with spontaneous or induced onset of labour. The secondary objectives will be to compare the effect of higher doses of oxytocin (intervention group) vs standard doses of oxytocin (control group) on maternal and labour complications (length of labour, arrest of labour, interruption of oxytocin perfusion and reason, uterine hyper-stimulation, mode of vaginal delivery, reason for caesarean section, post-partum haemorrhage, maternal blood transfusion, volume of oxytocin infusion, oxytocin side effects), as well as foetal complications and neonatal complications.
Interventions
DRUGOxytocin 4 mIU/mL
Oxytocin at 4 mIU/mL administrated by IV infusion controlled by pump or electric syringe.
DRUGOxytocin 2 mIU/mL
Oxytocin at 2 mIU/mL administrated by IV infusion controlled by pump or electric syringe.
Sponsors
Assistance Publique - Hôpitaux de Paris
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
An out-of-protocol healthcare professional (midwife / nurse) will prepare oxytocin. The out-of-protocol healthcare professional (midwife / nurse) will not be a study's investigator, and will not be involved in the patient's care. The randomization group will not be communicated to the investigator or any medical personnel involved in the study or patient by the out-of-protocol nurse/midwife, in order to preserve the double-blind design.
Intervention model description
There is two group of patient for which the prescription of oxytocin is required for the care : the control group will receive will receive oxytocin at 2 mIU/mL (standard dose) the experimental group will receive oxytocin at 4 mIU/mL
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Inclusion criteria are the following: * Age ≥ 18 years * Nulliparous (no previous childbirth beyond 22 SA) * BMI ≥ 30 kg/m² at the beginning of pregnancy * Singleton pregnancy * Spontaneous or induced onset of labour * Cephalic presentation * Term ≥ 37 weeks of gestation and \< 42 weeks of gestation * Medical Indication and absence of medical contraindication for oxytocin during labour: inadequate and/or ineffective uterine contraction and/or delayed cervical dilation * Written consent * Affiliation to a french social security system
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of caesarean section during labour | through study completion, an average of 1 month | The decision of caesarean section is made by the responsible obstetrician in charge of the patient, he or she will be blinded of the patient's group (oxytocin dosage) to avoid differential indication for caesarean section. Therefore, the decision to perform (or not) a caesarean section will be only based on foetal/maternal criteria, independently of oxytocin dosage. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reason for the caesarean section | through study completion, an average of 1 month | foetal heart anomalies / labour arrest / other |
| Interruption of oxytocin perfusion and causes | through study completion, an average of 1 month | Interruption of oxytocin perfusion (yes/no) and causes (foetal heart anomalies / uterine hyperkinesia / uterine hypertonia / other) |
| Uterine hyper-stimulation | Through study completion, an average of 1 month | Uterine hyper-stimulation (more than 5 uterine contractions per 10 min) |
| Length of labour phases | Through study completion, an average of 1 month | Length of labour phases is measured in minutes (from 2 cm of dilation until delivery) |
| Arrest of labour | Through study completion, an average of 1 month | It will be evaluated if there is two or more hours without cervical dilation (yes/no) |
| Mode of vaginal delivery | Through study completion, an average of 1 month | Spontaneous or operative delivery.If operative vaginal delivery: indication |
| Maternal blood transfusion | Through study completion, an average of 1 month | Maternal blood transfusion (yes/no) (for the duration of the hospitalization) |
| Volume of oxytocin infusion | Through study completion, an average of 1 month | Volume of oxytocin infusion (mL/H) |
| Oxytocin side effects | Through study completion, an average of 1 month | nausea, vomiting, headaches, increased or decreased heart rate, allergic reaction, skin rash |
| Foetal complications | Through study completion, an average of 1 month | * Foetal heart rate anomalies requiring second-line monitoring (as pH/lactate blood test at scalp) or emergency delivery (yes / no) * Appearance of meconium (yes / no) * Chorioamnionitis (yes/no): defined as the combination of 2 of the next 3 signs: maternal fever more than 38°5 during labour and/or foetal heart tachycardia and/or biological infection sign |
| Neonatal complications | Through study completion, an average of 1 month | * Apgar score at 5 min * Umbilical arterial cord pH * Neonatal resuscitation (yes / no): defined by at least artificial ventilation * Transfer to neonatal care unit (yes / no) |
| Post-partum haemorrhage | Through study completion, an average of 1 month | Post-partum haemorrhage (yes/no) and its volume (mL). Post-partum haemorrhage is defined as blood lost ≥ 500 mL in the 2 hours after birth. |
Countries
France
Outcome results
None listed