The provider orders an infusion of oxytocin to prevent postpartum hemorrhage at 20 mU/min.

The availability of the oxytocin infusion is 20 units/1000 mL of normal saline.

How many mL/hr will the oxytocin infuse. (Record numerical answers only. Round the answer to the nearest whole number.)

Choice A rationale

Prolonged rupture of membranes (PROM), especially beyond 18-24 hours, significantly increases the risk of intrauterine infection (chorioamnionitis) for both mother and fetus. Infection is a contraindication or at least a major caution for a trial of labor after cesarean (TOLAC) as it adds physiological stress and could necessitate an urgent repeat cesarean, complicating recovery. The normal range for time from rupture to delivery is generally under 24 hours.

Choice B rationale

A current separation of the symphysis pubis (diastasis symphysis pubis), often causing significant pelvic girdle pain and instability, presents a mechanical risk during labor and vaginal delivery. The excessive strain and pressure of pushing could exacerbate the separation, leading to severe maternal morbidity, chronic pain, and long-term musculoskeletal dysfunction, thus generally contraindicating a TOLAC.

Choice C rationale

Placenta previa, which occurs when the placenta covers the cervix, necessitating the previous cesarean, is an obstetric indication not expected to recur in subsequent pregnancies with the same certainty as issues like contracted pelvis or certain uterine incision types. With no recurrent previa and an otherwise favorable presentation, the client is a good candidate for a trial of labor after cesarean (TOLAC) because the prior indication was temporary.

Choice D rationale

A breech presentation, which describes the fetus positioned with the buttocks or feet first, was the fetal indication for the previous cesarean section. Assuming the current fetus is in a cephalic (head-down) presentation, this non-recurrent fetal issue makes the client a suitable candidate for a trial of labor after cesarean (TOLAC), as the uterus itself and the maternal pelvis are likely accommodating.

Choice E rationale

Group B streptococcal (GBS) colonization is a common bacterial finding in the lower genital tract, typically managed with prophylactic intravenous antibiotics (e.g., Penicillin) during labor. GBS positivity is a standard infectious risk factor managed with antibiotics and does not contraindicate a trial of labor after cesarean (TOLAC) itself, as it is routinely treated to prevent neonatal sepsis.

Choice F rationale

The gynecoid pelvis is considered the most favorable pelvic shape for vaginal delivery due to its rounded inlet, adequate mid-pelvis, and wide subpubic arch, which allows for optimal fetal head engagement and rotation. This favorable anatomy increases the likelihood of a successful trial of labor after cesarean (TOLAC) and is a strong positive predictive factor.

Choice A rationale

Labetalol is a combined α and β-adrenergic blocker and is a preferred first-line agent for managing chronic or gestational hypertension in pregnancy. It acts by reducing systemic vascular resistance and mildly decreasing heart rate, effectively lowering blood pressure while minimizing risks to the developing fetus due to its established safety profile.

Choice B rationale

Digoxin is a cardiac glycoside primarily used to treat heart failure and control the ventricular rate in atrial fibrillation. While not a primary antihypertensive, it may be used in pregnant clients with pre-existing heart failure, which can complicate chronic hypertension, making its prescription possible in this client population.

Choice C rationale

Warfarin, an oral anticoagulant, is a teratogen classified as Pregnancy Category D, as it readily crosses the placenta and is associated with the Warfarin embryopathy (nasal hypoplasia, stippled epiphyses) in the first trimester, and fetal hemorrhage, making it generally contraindicated in pregnancy. Low molecular weight heparin is preferred.

Choice D rationale

Nitroglycerin, a potent vasodilator, is a medication that can be used intravenously to quickly manage severe, acute hypertensive crises in pregnant clients, although it's not a medication for chronic daily use. Its rapid action and control of blood pressure make it a potential, albeit specialized, option in obstetric emergencies.