THE FACTS The patient, a 35-year-old gravida 2, para 0, presented to her obstetrician for antepartum care in February 1990 with a last menstrual period of 11/27/89 and an estimated date of confinement of 9/6/90. She was 12 weeks by dates and by ultrasound, and her physical examination was within normal limits. When the woman returned at 16 weeks' gestation, her examination and serum alpha-fetoprotein results were normal. Ultrasound was again within normal limits at 18.5 weeks, when the patient had her last documented prenatal visit.
On May 7, 1990, at approximately 22.5 weeks' gestation, the patient presented to the emergency room with complaints of intermittent back pain since the morning and constant groin pain for 3 months. She was dizzy and had noticed an increased watery, odorless discharge for 4 days. No amniotic fluid was seen within the vagina. At 7 PM, the patient was placed on an external fetal monitor, which displayed a fetal heart rate in the range of 130 to 150 bpm, with no maternal contractions. Vaginal examination showed "hourglassing" membranes, greenish mucus, and cervical dilation of approximately 2 cm. The impression was premature cervical dilatation with bulging membranes at 22 weeks, and the plan was to admit the patient, perform labs, obtain a group B beta-streptococcus (GBS) rectovaginal culture, and start the patient on IV ampicillin with strict bed rest in the Trendelenberg position.
On May 9, 1990, the patient complained of very mild contractions, and her cervix was 1 to 2 cm dilated with 50% effacement. Terbutaline was started with doses of 0.25 sq at 2 AM, repeated every 30 minutes for three doses and then switched to oral terbutaline 2.5 mg every 3 hours until 4 PM on May 11. The obstetricians discussed cerclage but discounted it because of the extent to which the fetal membranes were "hourglassing." The next day, the rectovaginal culture report revealed no GBS. Because the patient was "shaking" from the terbutaline and had no contractions, the medication was decreased to every 4 hours. She was to remain on bed rest for the duration of her pregnancy.
A nurse's note made at 8:30 PM on May 22 at 24.5 weeks' gestation describes the patient as having "contractions continuously for 7 minutes," at which time the woman's obstetrician ordered that terbutaline be given "stat." The woman's contractions stopped, but by noon the following day, she was once again complaining of two mild contractions, which then subsided. The patient's membranes ruptured at 5:30 PM on May 23and she was taken to the delivery room within 10 minutes and placed on an external fetal monitor. The FHR was consistently within the 120 to 150 bpm range, and the woman was leaking clear amniotic fluid. At 7:45 PM, the FHR was in the 145 to 160 bpm range, with moderate beat-to-beat variability and no uterine contractions. A nurse's note indicates the FHR decreased to 70 bpm but returned to baseline after the elevated head of the patient's bed was lowered. The FHR remained consistently within the 150 to 160 bpm baseline through 10:15 PM, and uterine contractions were occasional and mild throughout that period.