KAILUA KONA, HAWAII — An important step in detecting preterm labor in a multifetal pregnancy is to increase the patient's awareness of contractions and pelvic pressure and the need to report these symptoms, Dr. Michael A. Belfort said.
Most women who are pregnant for the first time don't know what contractions feel like or what to do if they get them. Spend time describing the sensations and instruct the patient about who to call, he said at a conference on obstetrics, gynecology, perinatal medicine, neonatology, and the law.
Dr. Belfort, professor of obstetrics and gynecology at the University of Utah, Salt Lake City, said medicolegal issues related to preterm birth in multifetal pregnancies tend to fall in the following categories:
▸ Prevention and diagnosis. There is little benefit from routine bed rest or hospitalization to prevent preterm labor in a multifetal pregnancy, the published evidence shows. It may make sense to hospitalize a woman with a high-risk pregnancy if there is a reason to continuously monitor contractions or fetal heart rate, but admitting someone with only occasional contractions just to have that person in the hospital generally is not helpful, he said. For patients with regular contractions, admission for a full evaluation may be the safest initial step.
Home uterine monitoring has not been shown to help improve outcomes in preterm birth, and the American College of Obstetricians and Gynecologists does not recommend its use. If you plan to follow cervical length measurements by ultrasound, consider also obtaining fetal fibronectin measurements. Some data are available that combine the two measures to estimate the risk of preterm birth, Dr. Belfort said at the meeting, which was sponsored by Boston University.
▸ Steroids. For singletons, it's the standard of care to give a single course of antenatal steroids when there's a high risk of preterm birth between 24 and 34 weeks' gestation if the membranes are intact or between 24 and 32 weeks when the membranes are ruptured and there is no infection. Although no prospective studies specifically recommend the same course of action for twins or higher-order multiples, it makes sense to give steroids in multifetal pregnancies at high risk of preterm birth in those time periods, and most physicians do, he said. Do not give more than one course of steroids, he added. Repeat courses may have harmful effects on fetal brain growth, according to emerging data.
▸ Tocolytics. At least seven prospective studies show there is no clear benefit to giving prophylactic tocolytic therapy to try to stop contractions. This strategy will not prevent preterm birth, improve birth weight, or reduce the risk of neonatal mortality. Probably the best one can hope for is to slow down labor for 48 hours, he said. The terbutaline pump has been associated with maternal cardiac arrhythmia, and ACOG does not support its use.
▸ Cerclage. Two prospective trials in twins found no benefit from prophylactic cerclage in preventing preterm birth. No prospective, randomized, controlled trials have been conducted with triplets.
▸ Follow-up. A multifetal pregnancy in preterm labor should be followed closely, whether in or out of the hospital. Giving hydration or antibiotics is not helpful in preventing preterm labor, although antibiotics should not be withheld if there is an infection. Studies are underway on the use of progesterone to reduce the risk of preterm birth in multifetal pregnancies, but this is not yet the standard of care. For singletons, two studies suggest that a weekly intramuscular injection of progesterone may be helpful when given to a pregnant woman with a history of preterm delivery that did not involve cervical incompetence or an abruption.
▸ Experience. Do not delay transferring a patient with a multifetal pregnancy at high risk for preterm delivery to a level 3 facility. Continue to manage only the pregnancies that you're equipped to handle to avoid a postbirth injury that might have been avoided with specialized neonatal care.