A 30-year-old woman, gravida 3 para 2, at 37 weeks gestation comes to labor and delivery for regular, painful contractions. The contractions started an hour ago and are now 3-4 minutes apart. She has had no leakage of fluid or vaginal bleeding. Fetal movement has been normal. At her prenatal visit last week, examination showed a cephalic fetal presentation; group B Streptococcus rectovaginal culture was negative. Today, temperature is 36.7 C (98 F), blood pressure is 110/80 mm Hg, and pulse is 88/min. Fetal heart rate tracing shows moderate variability, multiple accelerations, and no decelerations. Tocodynamometer shows contractions every 3-4 minutes. The abdomen is nontender when contractions subside. On digital cervical examination, the cervix is 4 cm dilated, 90% effaced, and a taut, bulging bag is palpable with no presenting fetal part. Which of the following is the best next step in management of this patient?

Question

A 30-year-old woman, gravida 3 para 2, at 37 weeks gestation comes to labor and delivery for regular, painful contractions.  The contractions started an hour ago and are now 3-4 minutes apart.  She has had no leakage of fluid or vaginal bleeding.  Fetal movement has been normal.  At her prenatal visit last week, examination showed a cephalic fetal presentation; group B Streptococcus rectovaginal culture was negative.  Today, temperature is 36.7 C (98 F), blood pressure is 110/80 mm Hg, and pulse is 88/min.  Fetal heart rate tracing shows moderate variability, multiple accelerations, and no decelerations.  Tocodynamometer shows contractions every 3-4 minutes.  The abdomen is nontender when contractions subside.  On digital cervical examination, the cervix is 4 cm dilated, 90% effaced, and a taut, bulging bag is palpable with no presenting fetal part.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_da48_7019_bc81_5d3f06397193_MD0003_00 Digital cervical examination is used to determine cervical dilation and fetal presentation (ie, the fetal part [eg, head, buttocks] directly overlying the pelvic inlet). Fetal presentation is variable and can change from week to week, even in term pregnancies. This patient at 37 weeks gestation is laboring and has a taut, bulging bag with no palpable presenting fetal part on cervical examination. Although digital cervical examination is usually adequate for determining fetal presentation, it may be insufficient in patients with a bulging bag (which may be a normal finding due to uterine contractions tensing the amniotic sac). If fetal presentation is indeterminate on cervical examination, a transabdominal ultrasound is performed to confirm presentation and help determine route of delivery. Patients with cephalic fetal presentation can be managed expectantly in anticipation of vaginal delivery. Conversely, breech or other noncephalic (eg, transverse) fetal presentations should be managed by cesarean delivery in order to avoid the increased risk of neonatal death associated with breech vaginal delivery (Choice B). transverse (Choice A) Amniotomy, or iatrogenic rupture of membranes, is no longer routinely performed on patients in spontaneous labor because it does not decrease the duration of the first stage of labor or reduce cesarean delivery rates. Additionally, in patients with no palpable presenting fetal part, a transabdominal ultrasound should be performed before amniotomy to avoid umbilical cord prolapse in patients with a funic (ie, cord first) presentation. funic (Choice C) An external cephalic version is performed to convert non-cephalic presentations to cephalic. Determination of fetal presentation via transabdominal ultrasound is performed prior to this procedure. external cephalic version (Choice D) Terbutaline, a beta-2 adrenergic agonist tocolytic, stops contractions by causing uterine relaxation. Terbutaline should not be administered without knowing the fetal presentation. If the fetus is cephalic, then terbutaline tocolysis will delay vaginal delivery. Educational objective: If fetal presentation (eg, cephalic, breech) is uncertain on digital cervical examination, a transabdominal ultrasound should be performed to confirm fetal presentation and determine the safest route of delivery. References: Planned caesarean section for term breech delivery. (http://www.ncbi.nlm.nih.gov/pubmed/26196961) ACOG committee opinion no. 745: mode of term singleton breech delivery. (http://www.ncbi.nlm.nih.gov/pubmed/30045211)

A 30-Year-Old Woman, Gravida 3 Para 2, at 37 Weeks