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 hematology.

The objective of this study was to establish normal fetal hematological parameters throughout gestation. Samples of pure fetal blood from 35 fetuses of 21-38 weeks' gestation were obtained by fetal blood sampling under continuous ultrasound guidance. The hematological parameters were determined with automated cell counter within 30 minutes after the procedures. Fetal red blood cell and granulocyte counts rose significantly with advancing gestation, whereas, the mean corpuscular volume fell. There were no significant changes in fetal hemoglobin, hematocrit, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red cell distribution width, total white blood cell count, lymphocyte count, mid-cell count, platelet count, mean platelet volume, and platelet distribution width with increasing gestation. The growing application of fetal blood sampling to the prenatal diagnosis renders mandatory a knowledge of normal fetal blood values. These results may provide useful reference values for prenatal diagnoses of hematological disorders.

Fetal complete heart block: an expectant management.

Fetal complete heart block is a rare cardiac arrhythmia occurring in prenatal life. The diagnosis usually requires a multimodality approach of imaging technology especially M-mode and Doppler ultrasound. The management guideline is not conclusive. We presented 2 cases of fetal complete heart block diagnosed prenatally. The fetuses were closely monitored conservatively and delivered at term. Permanent cardiac pacemakers were performed neonatally with satisfactory outcomes.

Nomogram of nuchal fold thickness of Thai fetuses.

The aim of the study was to establish normal values of nuchal fold thickness during 14-21 weeks of pregnancy. Three hundred Thai pregnant women before 12 weeks of gestation were recruited. Gestational age was determined by last menstrual period and confirmed by crown-rump length. Subjects with date-size discrepancy of more than 7 days were excluded from the study. Nuchal fold thickness was measured twice, first during 14-17 weeks, and then during 18-21 weeks. Five hundred and nine measurements were obtained. Nomogram of nuchal fold thickness was constructed. Mean values of nuchal fold thickness increased steadily from 2.59 +/- 0.77 millimeters (mm) at 14 weeks to 4.12 +/- 0.98 mm at 21 weeks. Average rate of increase were 0.22 mm per week. In conclusion, nuchal fold thickness increased with advancing gestational age from 14 to 21 weeks of pregnancy. Different normal cut-off levels for each gestational week may be more appropriate for screening of fetal Down syndrome in Thai pregnant women.

Intrauterine growth retardation: incidence, screening results, pregnancy outcome.

Intrauterine growth retardation is detrimental to the health of fetuses and neonates both immediately and in the long run. A risk scoring system to help screen for this complication has been developed as a result of this prospective study. With the incidence of intrauterine growth retardation at approximately 9 per cent in this study population, the final risk scoring system with its 6 variables and total score of 10 was found to be quite useful as a screening method because of its high sensitivity (91.18%) and high negative predictive value (98.14%). Screening by this risk scoring system should be helpful and prove practical among health personnel with varying levels of expertise and experience. Most gravidae had easy labour and delivered within 24 hours. Instrumental delivery rate was high with caesarean section rate of 17.6 per cent. Almost 70 per cent of the intrauterine growth retarded babies were symmetrical type and the perinatal mortality rate in this group was 42.3 which is approximately 4 times that in general population delivered at this hospital.