across three groups: small-for-gestational age (SGA) (BW <10%ile), appropriate-for-gestational age (AGA) (BW 10-90%ile), and largefor-gestational age (LGA) infants (BW >90%ile), with SGA as the reference group. Interval-censored regression estimated median duration of labor stratified by actual BW, as well as by labor type (spontaneous vs. induction) and parity (nulliparity vs. multiparity). RESULTS: Of 17,099 women, 5970 (34.9%) were induced and 6,457 (37.8%) were nulliparous; 2,457 (14.4%) and 908 (5.3%) women delivered SGA and LGA infants, respectively. After adjustment for obesity, epidural and prior cesarean, SGA infants progressed through labor significantly faster than AGA and LGA infants. Median time to dilate 4-10cm was 4.0 (5-95 th percentile, 1.2-13.4), 4.6 (1.4-15.6, p¼0.07), and 6.2 (1.8-21.1, p<0.01) hours in the SGA, AGA and LGA groups, respectively. Median time in active labor (6-10cm) was 1.1 (0.2-5.9), 1.6 (0.3-8.4, p<0.01) and 2.1 (0.4-11.3, p<0.01) hours in the SGA, AGA and LGA groups, respectively. Median time to progress 4-6cm was similar in SGA and AGA infants overall (p¼0.13), and remained similar for nulliparous women (p¼0.37) and labor induction (p¼0.34). Median time to progress 4-6cm was longer with LGA infants than with SGA infants overall (p<0.01) and when stratified by labor type (p<0.01) and parity (p<0.01). The difference in median time to dilate 6-10cm remained significant among all three BW groups even when stratified by labor type (p<0.01) and parity (p<0.01). CONCLUSION: After reaching 4cm cervical dilation, SGA infants have similar labor progression as AGA infants, particularly among nulliparous and induced women, but have faster progression compared to LGA infants until the active phase of labor is reached. SGA infants progress through active labor faster than AGA and LGA infants, irrespective of labor type and parity. Clinicians should consider fetal size when monitoring first stage labor progress and determining labor arrest.

No abstract

INTRODUCTION: Immersive virtual reality (VR) has recently been shown to be a valid method to treat pain and anxiety. This modality is very new to the childbirth process. One objective of this study was to show if, during labor, there is a pain level or time of day where virtual reality is less effective or desired, and what VR applications subjects enjoy using most. METHODS: This is a randomized control trial intended as a pilot study with 2 different arms of 10. Nurses periodically recorded information every 4 hours during latent labor and every 1 hour during active labor. VR arm patients were asked to use VR for at least 15 minutes and record pain scores again. Patients were allowed access to all standard forms of analgesia throughout labor. A brief survey was completed after delivery. IRB approval/informed consent was obtained. RESULTS: 100% of patient stopped using VR as labor progressed, even after getting epidurals with the average pain score of 8 in non-epiduralized patients. The average number of VR uses per patient was 3.1 +/- 0.99. 80% of patients' last use of VR prior to refusal was before 2300 hrs. The most enjoyed VR experience was playing games with 67%, and nature/meditation scenes were also preferred options. CONCLUSION: This study suggests that VR in labor has some parameters to optimal use. Patients tend to not desire VR use with pain scores >8, or at night time. When implementing VR during labor, patient preferences should be kept in mind to optimize its effectiveness.