Fetal transverse cerebellar diameter in Thai population.

We developed a nomogram for transverse cerebellar diameter (TCD) in Thai fetuses by recruitment of 153 normal pregnant women in the first trimester. The gestational age calculated by the certain last menstrual period and the first trimester ultrasound were in agreement. The pregnant women were stratified into 4 groups and scanned at four weekly intervals: group A was first scanned at 14 weeks, group B at 15 weeks, group C at 16 weeks, and group D at 17 weeks. A total of 699 measurements from 14 to 40 weeks of gestation were obtained. The data were analyzed for mean and standard deviation; and the best fit mathematical model was derived. The TCD grew progressively along gestational age. The growth rate was slightly less than that of a Western study after 28 weeks of gestation. This could serve as the basis for gestational dating in fetuses with aberrant fetal growth.

Sonographic findings in clinically diagnosed threatened abortion.

OBJECTIVE: To determine the sonographic appearances in pregnant women who presented with vaginal bleeding in the first 20 weeks of gestation. METHOD: Pregnant women of under 20 gestational weeks diagnosed clinically as threatened abortion were recruited for ultrasound scan at the Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University. The sonographic findings were reported as viable pregnancy, anembryonic pregnancy, embryonic death, incomplete abortion, complete abortion, ectopic pregnancy, molar pregnancy and inconclusive findings. Patients with inconclusive findings were followed weekly until final diagnoses were established. All patients were followed-up to 20 weeks or until the final outcomes were revealed. RESULTS: Two hundred and sixty eight pregnant patients were enrolled. Ultrasound scans demonstrated 100 viable fetuses (37.3%), 73 embryonic deaths (27.3%), 46 anembryonic pregnancies (17.2%), 6 molar pregnancies (2.2%), 3 ectopic pregnancies (1.1%), 14 complete abortions (5.2%) and 26 inconclusive findings (9.7%). Follow-up scan on patients with inconclusive findings revealed 9 anembryonic pregnancies (3.3%), 9 incomplete abortions (3.3%), 1 embryonic death (0.4%) and 1 viable pregnancy (0.4%). Six patients (2.3%) were lost to follow-up. The viable pregnancy rate according to maternal age was highest at the maternal age of 25 to 29 years old (49%), whereas, it was lowest at the maternal age of 40 to 44 years old (0%). The viable pregnancy rate according to gestational age was highest at 6 to 8 weeks (61.2%), whereas, it was lowest at 18 to 20 weeks (20%). CONCLUSION: Sonographic findings in patients with clinically diagnosed threatened abortion demonstrated viable pregnancies in around one-third of the cases. Use of ultrasound in clinically diagnosed threatened abortion may assist clinicians in establishing a definite diagnosis so that appropriate care could be offered to the patients.

Transvaginal sonography for fetal crown-rump length measurement in a Thai population.

A prospective descriptive cross-sectional study was undertaken at the Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University to establish a reference interval for fetal crown-rump length (CRL) in a Thai population using transvaginal ultrasound. This study was performed on normal pregnant women registered at the antenatal clinic in their first trimester. All had a good menstrual history. CRL measurement was obtained by a 5 MHz vaginal probe. All of the newborns were proved to be normal at birth. We constructed and compared CRL (mm) relating to gestational age (GA) (days). Five hundred and forty seven cases were enrolled into the study. CRL was correlated with gestational age. The best fit regression equation was the quadratic model: CRL (mm) = -13.872 - 0.014 GA (day) + 0.0097 GA (day)2, R = 0.92, p < 0.0001). Centiles and a chart for CRL derived from the regression equation are presented. In conclusion, a reference interval for fetal crown-rump length in a Thai population has been established. This data may be useful in the early detection of genetic or environmental disorders affecting fetal growth in the first trimester of pregnancy.

Fetal acoustic stimulation for rapid intrapartum assessment of fetal well-being.

Fetal heart rate reactions to the fetal acoustic stimulation test (FAST) were prospectively studied in 140 women in early labor. Overall 45 of 140 patients (32%) had one or more complications of pregnancy. All were in the latent phase of labor with a singleton, vertex-presenting fetus. Gestational age ranged from 37-43 wks. The women were screened with a 15-20 min fetal heart rate recording (FHR admission test) before the acoustic stimulation was applied. Results of the FHR admission test and the FAST in women were compared with fetal outcome; which was considered poor when there was perinatal death, a 5 min Apgar score less than 7, fetal distress requiring cesarean section, thick meconium stained amniotic fluid or admission to the neonatal intensive care unit. FAST had better sensitivity (71.4% vs 42.8%), specificity (99.2% vs 97.7%), positive predictive value (83.3% vs 50.0%) and negative predictive value (98.5% vs 97.0%) for poor fetal outcome than the FHR admission test. Fetal acoustic stimulation test in the early intrapartum period may be used as a noninvasive screening method for rapid intrapartum assessment of fetal wellbeing. It may discriminate the compromised from the noncompromised fetus. This clinical application can be helpful in a busy labor room when rapid assessment of fetal health is required.