OBJECTIVE: To investigate the relationship between the timing of disappearance of high-resistance uterine artery waveforms between the first and second trimester of pregnancy and birth weight. METHODS: Uterine artery ...OBJECTIVE: To investigate the relationship between the timing of disappearance of high-resistance uterine artery waveforms between the first and second trimester of pregnancy and birth weight. METHODS: Uterine artery Doppler recordings were obtained in a cohort of singleton pregnancies at 11-14 weeks of gestation and subsequently at 18-23 weeks. At each examination, the presence or absence of an early diastolic notch was recorded for each side. An abnormal pattern of blood flow was defined as the presence of bilateral notches. Cases complicated by preeclampsia or preterm delivery were excluded. RESULTS: Four hundred eleven pregnancies showed absent or unilateral uterine artery notches at the 11-14-week scan (group 1). All these cases maintained a low-resistance uterine blood flow pattern at the second-trimester scan. Of the 251 pregnancies with bilateral notches at the 11-14-week scan, 222 subsequently displayed a low-resistance blood flow at 18-23 weeks (group 2) whereas only 29 maintained bilateral notches (group 3). The mean birth weight was higher in group 1 (3,452 g) than in groups 2 (3,310 g) and 3 (3,224 g). This difference was confirmed after adjusting for confounding variables. Small-for-gestational-age fetuses were more common in groups 2 (14.9%) and 3 (14%) compared with group 1 (6.8%, P < .001). During the study period, severe preterm preeclampsia was observed in 6 cases only. CONCLUSION: The longitudinal variation in uterine artery blood flow pattern has a statistically significant correlation with birth weight, likely reflecting the timing and degree of trophoblastic invasion of the maternal vessels.展开更多
Objective: To assess the effect of parity on endovascular trophoblastic invasion in early pregnancy. Design: Observational study. Setting: Teaching hospital. Patient(s): Healthy women at 10-14 weeks of gestation. Inte...Objective: To assess the effect of parity on endovascular trophoblastic invasion in early pregnancy. Design: Observational study. Setting: Teaching hospital. Patient(s): Healthy women at 10-14 weeks of gestation. Intervention(s): Surgical termination of pregnancy for nonmedical reasons. Main Outcome Measure(s): Products of conception were blindly examined histologically with regard to the extent of decidual endovascular trophoblast invasion. Result(s): Samples were obtained from 20 nulliparous and 10 parous women. The presence of normal intradecidual endovascular trophoblast invasion was identified with a similar frequency in both groups (P=.28). However, the proportion of decidual vessels with endovascular trophoblast invasion was significantly higher in parous women (60% ) compared with nulliparous women (32% , P < .001). Conclusion(s): Endovascular trophoblast invasion in early pregnancy is more extensive in parous women who already had an uncomplicated pregnancy than in nulliparous women.展开更多
文摘OBJECTIVE: To investigate the relationship between the timing of disappearance of high-resistance uterine artery waveforms between the first and second trimester of pregnancy and birth weight. METHODS: Uterine artery Doppler recordings were obtained in a cohort of singleton pregnancies at 11-14 weeks of gestation and subsequently at 18-23 weeks. At each examination, the presence or absence of an early diastolic notch was recorded for each side. An abnormal pattern of blood flow was defined as the presence of bilateral notches. Cases complicated by preeclampsia or preterm delivery were excluded. RESULTS: Four hundred eleven pregnancies showed absent or unilateral uterine artery notches at the 11-14-week scan (group 1). All these cases maintained a low-resistance uterine blood flow pattern at the second-trimester scan. Of the 251 pregnancies with bilateral notches at the 11-14-week scan, 222 subsequently displayed a low-resistance blood flow at 18-23 weeks (group 2) whereas only 29 maintained bilateral notches (group 3). The mean birth weight was higher in group 1 (3,452 g) than in groups 2 (3,310 g) and 3 (3,224 g). This difference was confirmed after adjusting for confounding variables. Small-for-gestational-age fetuses were more common in groups 2 (14.9%) and 3 (14%) compared with group 1 (6.8%, P < .001). During the study period, severe preterm preeclampsia was observed in 6 cases only. CONCLUSION: The longitudinal variation in uterine artery blood flow pattern has a statistically significant correlation with birth weight, likely reflecting the timing and degree of trophoblastic invasion of the maternal vessels.
文摘Objective: To assess the effect of parity on endovascular trophoblastic invasion in early pregnancy. Design: Observational study. Setting: Teaching hospital. Patient(s): Healthy women at 10-14 weeks of gestation. Intervention(s): Surgical termination of pregnancy for nonmedical reasons. Main Outcome Measure(s): Products of conception were blindly examined histologically with regard to the extent of decidual endovascular trophoblast invasion. Result(s): Samples were obtained from 20 nulliparous and 10 parous women. The presence of normal intradecidual endovascular trophoblast invasion was identified with a similar frequency in both groups (P=.28). However, the proportion of decidual vessels with endovascular trophoblast invasion was significantly higher in parous women (60% ) compared with nulliparous women (32% , P < .001). Conclusion(s): Endovascular trophoblast invasion in early pregnancy is more extensive in parous women who already had an uncomplicated pregnancy than in nulliparous women.
