Objective The purpose of this study was to evaluate the impact of noncentral placental cord insertion on birthweight discordance in twins. Study Design We performed a multicenter, prospective trial ...of twin pregnancies. Placental cord insertion was documented as central, marginal, or velamentous according to a defined protocol. Association of the placental cord insertion site with chorionicity, birthweight discordance, and growth restriction were assessed. Results Eight hundred sixteen twin pairs were evaluated; 165 pairs were monochorionic, and 651 pairs were dichorionic. Monochorionic twins had higher rates of marginal ( P = .0068) and velamentous ( P < .0001) placental cord insertion. Noncentral placental cord insertion was more frequent in smaller twins of discordant pairs than control pairs (29.8% vs 19.1%; P = .004). Velamentous placental cord insertion in monochorionic twins was associated significantly with birthweight discordance (odds ratio, 3.5; 95% confidence interval, 1.3–9.4) and growth restriction (odds ratio, 4; 95% confidence interval, 1.1–14.3). Conclusion Noncentral placental cord insertion contributes to birthweight discordance in monochorionic twin pregnancies. Sonographic delineation of placental cord insertion may be of value in antenatal assessment of twin pregnancies.
Objective We sought to evaluate the association between placental histological abnormalities and birthweight discordance and growth restriction in twin pregnancies. Study design We performed a ...multicenter, prospective study of twin pregnancies. Placentas were examined for evidence of infarction, retroplacental hemorrhage, chorangioma, subchorial fibrin, or abnormal villus maturation. Association of placental lesions with chorionicity, birthweight discordance, and growth restriction were assessed. Results In all, 668 twin pairs were studied, 21.1% monochorionic and 78.9% dichorionic. Histological abnormalities were more frequent in placentas of smaller twins of birthweight discordant pairs ( P = .02) and in placentas of small for gestational age infants ( P = .0001) when compared to controls. The association of placental abnormalities with both birthweight discordance and small for gestational age was significant for dichorionic twins ( P = .01 and .0001, respectively). No such association was seen in monochorionic twins. Conclusion In a large, prospective, multicenter study, we observed a strong relationship between abnormalities of placental histology and birthweight discordance and growth restriction in dichorionic, but not monochorionic, twin pregnancies.
Objective Vaginal breech delivery rates have been accepted widely to be in decline and the Term Breech Trial (TBT) has recommended delivery of a breech-presenting infant by elective cesarean section ...delivery. Our aim was to examine the rate of vaginal delivery of term breech pregnancies in the 8 years before and after the publication of the TBT. Study Design We retrospectively examined vaginal delivery rates of breech presentations over a 16-year period in 3 large tertiary maternity hospitals that serve a single large metropolitan population. All 3 hospitals are of similar size and serve a population with similar risk profile. We also examined rates of perinatal mortality in the 3 hospitals over the study period. Results During the 16-year study period, there were 344,259 deliveries among the 3 hospitals; 11,913 of which were breech deliveries. There were 5655 breech deliveries in the 8 years before the publication of the TBT, with a cesarean delivery rate of 76.9%. There were 6258 breech deliveries in the 8 years since publication of the TBT, and the cesarean delivery rate increased to 89.7% ( P < .0001). During the 8 years since publication, the rate of vaginal delivery in nulliparous women decreased from 15.3-7.2% ( P < .0001). The vaginal breech delivery rate in multiparous women decreased from 32.6-14.8% ( P < .0001). The rates of corrected perinatal mortality showed a significant decrease in the last 4 years of the study. Conclusion Our study demonstrates that the results and recommendations of the TBT have contributed to decreasing vaginal breech delivery rates, which were already in decline before its publication.
Platelet reactivity and pregnancy loss Flood, Karen, MD; Peace, Aaron, PhD; Kent, Etaoin, MD ...
American journal of obstetrics and gynecology,
09/2010, Letnik:
203, Številka:
3
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Objective We sought to critically evaluate platelet function in recurrent miscarriage (RM). Study Design We conducted a prospective study comparing 30 patients with unexplained recurrent ...first-trimester pregnancy loss with 30 control subjects matched for age and serum progesterone level. Platelet function was determined using a modified assay of light transmission aggregometry with multiple agonists at different concentrations. Dose-response curves were created and half-maximal effective concentration values were calculated. Results At test completion the half-maximal effective concentration values for arachidonic acid in the patients with RM were significantly less than in the control subjects (0.153 vs 0.230; P = .0099). The dose-response curves were tightly matched for the other agonists. Conclusion This novel measurement of platelet function has demonstrated that patients with unexplained RM have significantly increased platelet aggregation in response to arachidonic acid. The enhanced response to this agonist provides an empirical rationale for the use of aspirin in management of this clinical condition.
