ABSTRACT
OBJECTIVE: To evaluate the diagnostic additional value of routine alpha-foetoprotein (AFP) assessment in amniotic fluid for the detection of neural tube defects (NTDs), compared with week 20 ultrasonographic examination. DESIGN: Retrospective. METHOD: We retrospectively determined AFP concentrations in amniotic fluid obtained from 7981 women who had undergone amniocentesis for karyotyping and AFP assessment. An AFP concentration greater than 2.5 times the median was considered abnormal. Women were categorised into 4 groups based on the indication for invasive prenatal diagnostic assessment: advanced maternal age (group I; n = 6179), increased risk of foetal NTDs (group II; n = 258), ultrasonographically confirmed foetal NTDs (group III; n = 55) or other indications (group IV; n = 1489). RESULTS: In group I, 18 of 6179 samples had increased AFP levels (0.3%), 2 of which were associated with NTDs. In group II, 2 of 258 samples had increased AFP levels (0.8%); both were associated with NTDs. Increased AFP levels were found in 44 of 55 samples from group III (80%), and 223 of 1489 samples from group IV (15.0%). CONCLUSION: Routine assessment of AFP in amniotic fluid based on advanced maternal age provides little additional value in the detection of NTDs beyond that of week 20 ultrasound.
ABSTRACT
The objective of this paper was to determine whether first- and second-trimester uterine artery Doppler velocimetry are associated with pregnancy complications in women of advanced maternal age. A prospective cohort study of 352 women aged 35 years and older was studied. The pulsatility index (PI) values at 12-13 weeks of gestation were significantly associated with development of hypertensive disorders, a small-for-gestational-age infant and gestational diabetes, with a relative risk exceeding 4, 2 and 8, respectively for women with PI values in the highest quartile (> 1.67) of the PI distribution when compared with the lowest quartile of the PI distribution (< 1.24). At 23-27 weeks' gestation, uterine artery PI values were found to be associated with preterm delivery with a gestational age-adjusted risk of 10.6 for women with PI values in the highest quartile of PI (> 1.24) when compared with PI values in the lowest quartile of the PI distribution (< 1.09). No associations existed between uterine artery PI, antepartum hemorrhage and Cesarean section rate. The risk estimates for any of the outcome parameters were not affected by maternal age. Results indicate that hemodynamic changes detectable in the uterine artery as early as the first trimester of pregnancy are associated with an increased risk of hypertensive disorders, a small-for-gestational-age infant and gestational diabetes. A similar association exists in the late second trimester of pregnancy, with an increased risk of preterm delivery.
