The National Institute for Health and Care Excellence recommends that if after a woman has been provided information on the risk of a planned caesarean section and she still insists on the procedure it should be provided. If provided this should be done at 39 weeks of gestation or later. There is no evidence that ECS can reduce mother-to-child hepatitis B and hepatitis C virus transmission. By characteristics of the mother Caesarean delivery on maternal request Caesarean delivery on maternal request (CDMR) is a medically unnecessary caesarean section, where the conduct of a childbirth via a caesarean section is requested by the pregnant patient even though there is not a medical indication to have the surgery. Systematic reviews have found no strong evidence about the impact of caesareans for nonmedical reasons. Recommendations encourage counseling to identify the reasons for the request, addressing anxieties and information, and encouraging vaginal birth. Elective caesareans at 38 weeks in some studies showed increased health complications in the newborn. For this reason ACOG and NICE recommend that elective caesarean sections should not be scheduled before 39 weeks gestation unless there is a medical reason. Planned caesarean sections may be scheduled earlier if there is a medical reason. After previous caesarean Mothers who have previously had a caesarean section are more likely to have a caesarean section for future pregnancies than mothers who have never had a caesarean section. There is discussion about the circumstances under which women should have a vaginal birth after a previous caesarean. Vaginal birth after caesarean (VBAC) is the practice of birthing a baby vaginally after a previous baby has been delivered by caesarean section (surgically). According to the American College of Obstetricians and Gynecologists (ACOG), successful VBAC is associated with decreased maternal morbidity and a decreased risk of complications in future pregnancies. According to the American Pregnancy Association, 90% of women who have undergone caesarean deliveries are candidates for VBAC. Approximately 60–80% of women opting for VBAC will successfully give birth vaginally, which is comparable to the overall vaginal delivery rate in the United States in 2010. Twins For otherwise healthy twin pregnancies where both twins are head down a trial of vaginal delivery is recommended at between 37 and 38 weeks. Vaginal delivery in this case does not worsen the outcome for either infant as compared with caesarean section. There is controversy on the best method of delivery where