Inclusion curve too slow.

Despite the fact that a link between cholesterol and the myometrium has been clearly established, no study investigating aspects of cholesterol metabolism and uterine dystocia currently exists. This study is a pilot study whose aim is to test the hypothesis that an association between uterine dystocia and single-nucleotide polymorphisms (SNPs) in the genes coding for the LXRs.

Inclusion Criteria:

• Patients undergoing C-section for a dystocia: 2 to 3 hours of stagnation in labor progress are observed (ie no increasing dilation, and uterine contractions less that 3-5 per 10 minutes) in spite of measures taken to overcome dystocia (oxytocin injection and artificial breaking of waters)
• the child is alive
• the child does not have apriori known malformations that could interfere with a vaginal birth
• foetus in cephalic position
• full term pregnancy (>= 37 weeks of amenorrhea)
• single birth
• patient has signed consent
• patient is affiliated with a social security system

Exclusion Criteria:

• vaginal birth
• programmed C-section
• C-section is chosen because the fetus has a cardia rhythm problem, and there is no stagnation in the labor process
• multiple pregnancy
• the child is in a breech position
• premature birth (<37 weeks amenorrhea)
• in utero fetal death
• fetal malformation known before birth that could interfere with a vaginal birth
• non french-speaking patient (impossible to correctly inform the patient)
• patient under guardianship

The study population represents women undergoing a difficult, stagnating labor due to either physical or uterine dystocia.