Biomedical subjects

Roger B Newman

Publications and source records attributed to Roger B Newman.

23 records · Page 2Linked to original sources

PubMed2003

Body mass index--specific weight gains associated with optimal birth weights in twin pregnancies.

OBJECTIVE: To formulate maternal weight gain guidelines, by maternal pregravid body mass index (BMI) status, associated with optimal fetal growth and birth weight in twins. STUDY DESIGN: This historical cohort study was based on 2,324 pregnancies with nonanomalous, liveborn twins (4,684 infants) from Ann Arbor, Charleston, Baltimore and Miami. Rates of maternal weight gain and fetal growth were modeled using multiple regression for 0-20 weeks, 20-28 weeks and 28-38 weeks (projected as necessary), controlling for potentially confounding factors. Optimal rates of fetal growth were defined as growth between the singleton and twin 50th percentiles, and optimal birth weights were defined as between the singleton 50th percentile and twin 90th percentile at > or = 36 weeks (2,850-2,950 g). RESULTS: Optimal rates of fetal growth and birth weights were associated with rates of maternal weight gain for underweight women of 1.25-1.75 lb/wk (0.57-0.79 kg/wk) to 20 weeks, 1.50-1.75 lb/wk (0.68-0.79 kg/wk) between 20 and 28 weeks and 1.25 lb/wk (0.57 kg/wk) from 28 weeks to delivery; for normal-weight women, 1-1.5 lb/wk (0.45-0.68 kg/wk) to 20 weeks, 1.25-1.75 lb/wk (0.57-0.79 kg/wk) between 20 and 28 weeks and 1.0 lb/wk (0.45 kg/wk) from 28 weeks to delivery; for overweight women, 1-1.25 lb/wk (0.45-0.57 kg/wk) to 20 weeks, 1-1.5 lb/wk (0.45-0.68 kg/wk) between 20 and 28 weeks and 1 lb/wk (0.45 kg/wk) from 28 weeks to delivery; for obese women, 0.75-1 lb/wk (0.34-0.45 kg/wk) to 20 weeks, 0.75-1.25 lb/wk (0.34-0.57 kg/wk) between 20 and 28 weeks and 0.75 lb/wk (0.34 kg/wk) from 28 weeks to delivery. CONCLUSION: Optimal rates of fetal growth and birth weights in twins are achieved at rates of maternal weight gain that vary by period of gestation and maternal pregravid BMI status.

Adult↗

PubMed2003

Uterine contraction frequency before and after successful tocolytic therapy for preterm uterine contractions.

OBJECTIVE: To examine the association between prelabor uterine contraction frequency (UCF) and the success of tocolytic therapy for preterm labor (PTL). STUDY DESIGN: Eleven centers conducted a prospective, observational study of UCF recorded between 22(0/7) and 36(6/7) weeks' gestational age or until delivery > or = 2 times/d on > or = 2 d/wk in women with singleton pregnancies with and without risk factors for preterm birth. Uterine contraction data obtained from patients diagnosed with PTL allowed comparison of mean UCF both before and after an acute episode of PTL treated with either intravenous, subcutaneous or oral tocolysis. The signed rank test was used to analyze differences in UCF before and after tocolytic therapy and between women who were or were not successfully treated with a labor-inhibiting agent. RESULTS: Of 454 enrolled women, 128 were diagnosed with PTL, and 74 were successfully treated with a labor-inhibiting agent. The mean UCF preceding PTL was not different between those women successfully treated and those who delivered as a consequence of the PTL episode. There was no difference (P = .653) in mean UCF between the week before PTL (UCF 0.60 +/- 0.8, median 0.30) and the first week of monitoring after successful tocolysis (UCF 0.82 +/- 1.4, median 0.27). CONCLUSION: The mean UCF immediately preceding PTL does not predict tocolytic success or failure.

Adult↗

PubMed2002

Frequency of uterine contractions and the risk of spontaneous preterm delivery.

BACKGROUND: The measurement of the frequency of uterine contractions has not been useful for reducing the rate of preterm delivery in randomized trials. Nonetheless, ambulatory monitoring of contractions continues to be used in clinical practice. METHODS: We assessed the frequency of uterine contractions as a predictor of the risk of spontaneous preterm delivery before 35 weeks of gestation. We enrolled women with singleton pregnancies between 22 and 24 weeks of gestation. The women used a contraction monitor at home to record contraction frequency twice daily on 2 or more days per week from enrollment to delivery or 37 weeks of gestation. RESULTS: We obtained 34,908 hours of successful monitoring recordings from 306 women. Although more contractions were recorded from women who delivered before 35 weeks than from women who delivered at 35 weeks or later, we could identify no threshold frequency that effectively identified women who delivered preterm infants. The sensitivity and positive predictive value of a maximal hourly frequency of contractions of four or more between 4 p.m. and 3:59 a.m. were 9 percent and 25 percent, respectively, at 22 to 24 weeks and 28 percent and 23 percent at 27 to 28 weeks. Other proposed screening tests, such as digital and ultrasound evaluations of the cervix and assays for fetal fibronectin in cervicovaginal secretions, also had low sensitivity and positive predictive value for preterm labor. CONCLUSIONS: Although the likelihood of preterm delivery increases with an increased frequency of uterine contractions, measurement of this frequency is not clinically useful for predicting preterm delivery.

Cervix Uteri↗

PubMed2002

Effect of cerclage on obstetrical outcome in twin gestations with a shortened cervical length.

OBJECTIVE: Our purpose was to determine the impact of cerclage placement on obstetric outcome in twin gestations with a shortened cervical length. STUDY DESIGN: A prospective cohort study of 147 consecutive twin pregnancies (July 1994 to March 2001) who underwent transvaginal ultrasonographic cervical length measurement between 18 and 26 weeks' gestation. Cerclage was offered to women with cervical lengths < or = 25 mm. Patients were segregated into quartiles by cervical length. Regression analysis and chi(2) tests were used to determine the effect of cervical length and cerclage on parameters of prematurity. RESULTS: One hundred twenty-eight twin gestations met inclusion criteria, including 21 (16.4%) who underwent cerclage for a cervical length < or = 25 mm. Decreasing cervical length was significantly associated with a shorter length of gestation, lower combined birth weight, delivery at < or = 34 weeks, preterm premature rupture of fetal membranes, and very low birth weight. None of these outcomes was altered by cerclage placement. CONCLUSION: Midtrimester cerclage does not alter the risks of prematurity associated with a shortened cervical length in twin gestations.

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PubMed2002

The association between maternal factors and perinatal outcomes in triplet pregnancies.

OBJECTIVE: The purpose of this study was to evaluate the associations between maternal factors and outcomes in triplet pregnancies. STUDY DESIGN: This was a historic cohort study of 194 triplet pregnancies of >or=24 weeks of gestation that were delivered from 1983 through 2001 from five medical centers. RESULTS: In analyses that were limited to pregnancies with all live-born triplets (178 pregnancies), women with a previous good outcome (>2500 g + >37 weeks of gestation) had longer gestations (+7.9 days, P =.03), better rates of fetal growth (+4.9 g/wk, P <.0001), and higher birth weights (+153 g, P <.0001). Maternal weight gains of <36 pounds by 24 weeks of gestation were associated with lower birth weights (-197 g, P <.0001), and fetal growth rates at <or=25th percentile were associated with a shorter length of gestation (-36.7 days, P <.0001). CONCLUSION: Previous obstetric outcome and weight gain by 24 weeks of gestation were associated significantly with fetal growth rate and birth weight; fetal growth rate, in turn, was associated significantly with length of gestation.

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