Limited information is available on the seroprevalence of chikungunya virus (CHIKV) infection and maternal-fetal transmission incidence of CHIKV and dengue virus (DENV) infections during the 2008-2009 CHIKV outbreak in southern Thailand. A community-based post-epidemic seroprevalence study was conducted in parturient women admitted to the Thepa District Hospital in Songkhla Province, Thailand, for delivery from November 2009 to May 2010. The women were tested for chikungunya (CHIK) IgM/IgG and dengue (DEN) IgM/IgG. Cord blood samples were also tested for CHIK IgM or DEN IgM in women who tested positive for CHIK IgM or DEN IgM, respectively. The seroprevalence of CHIKV infection (CHIK IgM or IgG positive) was 227/319 (71·2%) with pre-outbreak seroprevalence (IgM-/IgG+) of 43·6% and the seroprevalence of DENV infection was 288/319 (90·3%). Complications during pregnancy, newborn outcomes and congenital anomalies were not different in those who had recent, remote or no CHIKV infections. None of the newborns whose mothers were CHIK or DEN IgM positive had cord blood positive for both CHIK and DEN IgM. In conclusion, both CHIKV and DENV are endemic in southern Thailand; during the recent CHIKV outbreak CHIK seroprevalence increased from 43·6% to 71·2%.

Objective: To study the etiology and outcome of non-immune hydrops fetalis in southern Thailand. Methods: The medical records and videotape recordings of all pregnant women diagnosed with non-immune fetal hydrops, from January 1993 to December 2002 were reviewed. Results: Non-immune hydrops fetalis was documented in 71 cases. The causes of fetal hydrops were identified in 87.3%. Homozygous α-thalassemia-1 dominated as the cause of non-immune fetal hydrops (28.2%), followed by structural abnormalities (15.5%) and infection (12.7%). The underlying etiology remained unknown in 9 cases (12.7%). The overall survival rate of non-immune hydrops fetalis cases was 4.2%. Spontaneous regression occurred in 2 cases. Two cases were lost to follow up after initial evaluation. Termination of pregnancy was performed in 47 cases. There were 12 dead fetuses in utero, 2 stillbirths, 5 early neonatal deaths and only 3 cases survived. Conclusions: Homozygous α-thalassemia-1 is the most common cause of non-immune hydrops fetalis in southern Thailand, and the overall prognosis of non-immune hydrops fetalis is poor. We suggest that an effective thalassemia-screening program for prevention and control of homozygous α-thalassemia-1 be established in all areas where the α-thalassemia-1 gene is prevalent.

ObjectiveTo compare the pregnancy outcome between pregnancies affected and not affected by thalassemia trait.MethodsA retrospective case–control cohort study was conducted on singleton pregnant women who attended antenatal care and delivered at Songklanagarind Hospital. All of the participating thalassemia trait pregnant women were diagnosed based on hemoglobin typing and/or DNA analysis. A ratio of around 1–1 was used to compare their pregnancy outcomes with normal pregnant women.ResultsSeven hundred thirty-nine thalassemia trait and 799 normal pregnant women were included in the study. All of the women were Thai nationals living in the Southern Region of Thailand and nearly all of them had spontaneously conceived. Maternal complication rates of gestational diabetes, preterm birth, antepartum bleeding, postpartum bleeding, shoulder dystocia and puerperal morbidity, and the rates of neonatal complications: macrosomia, fetal weight <2,000 g, intrauterine growth restriction (IUGR), stillbirth, low Apgar score (<7) at 1 and 5 min and NICU admission, were not significantly different between the two groups. The rate of pre-eclampsia, however, was significantly different, with RRs of 1.73 (CI 1.01–3.00).ConclusionThe thalassemia trait condition did not affect the risk of gestational diabetes, postpartum hemorrhage, stillbirth, preterm birth and puerperal morbidity. However, pre-eclampsia should be warranted especially among nulliparous and high-BMI pregnant women.

Scrub typhus is a rickettsian disease which is seldom found in pregnancy. A 31-year-old, 34 weeks pregnant woman presented with fever, chill and cough for 6 weeks. Fetal jeopardy was found then a cesarean section was performed to deliver a 2,200 g male with hepatosplenomegaly. The mother's diagnosis was confirmed by positive Weil-Felix (OXK titer 1:320) and scrub typhus (titer 1:1600) tests. Vertical transmission was also demonstrated by a positive scrub typhus IgM in her child.

Most pregnant women had inadequate knowledge of Down syndrome and the screening test. However, they did have a positive attitude and were willing to accept the test. Providing knowledge on Down syndrome and the screening test for pregnant women should be implemented in our antenatal care services and community.

BackgroundNasal bone assessment has been incorporated into Down syndrome screening in first trimester. Several studies have established the normal reference values for fetal nasal bone length in the first trimester, which were found to be varied by population. However, the study on reliability of nasal bone length measurement was limited with contradictory results. This study aimed to investigate the reliability of fetal nasal bone length measurement at 11–14 weeks of gestation in the Thai population.MethodsA total of 111 pregnant women at 11–14 weeks of gestation attending for the routine first-trimester ultrasound examination were recruited. Each case was measured separately by two examiners. Examiner 1 performed the first measurement in all cases; any of the other 5 examiners consecutively performed the second measurement. Three independent measurements were performed by each examiner and they were blinded to the results of the others. Intraobserver and interobserver variabilities were evaluated with the intraclass correlation coefficient (ICC).ResultsNasal bone measurement was successfully performed in 106/111 cases (95.5%) by at least one examiner; 89 cases were performed by two examiners. The intraobserver variability was excellent for all examiners (ICC, 0.840-0.939). The interobserver variability between different pairs of examiners varied from moderate to excellent (ICC, 0.467-0.962). The interobserver variability between examiner 1 and any other examiner was good (ICC, 0.749). The Bland-Altman plot of the interobserver differences of nasal bone length measurements between examiner 1 and any other examiner showed good agreement.ConclusionsThe reliability of the fetal nasal bone length measurement at 11–14 weeks of gestation was good. The nasal bone length measurement was reproducible. Ethnicity has an effect on fetal nasal bone length, but reliability of nasal bone length measurement is critical to accuracy of screening and should be audited on an ongoing basis.

Aims: To establish the normative data distribution of nuchal translucency (NT) thickness in Thai fetuses. Methods: A cross-sectional multicenter study was conducted among 6,455 women with singleton pregnancies and gestational age between 10 and 14 weeks. For each case, the fetal crown-rump length (CRL) and NT were measured by transabdominal ultrasound. Transvaginal ultrasounds were used in poorly visualized cases. The distribution values of the NT thicknesses and their corresponding 10-mm CRL intervals between 45 and 84 mm were examined to obtain the median and 95th percentiles. Quantile regression modeling across the CRLs was performed to obtain the reference values. Results: Transabdominal ultrasound measurements were successfully done on 6,347 fetuses with 39 cases by the transvaginal route. Fetuses with CRL between 45 and 84 mm and normal outcomes made up a total of 4,352 cases. The mean (SD) gestational age, CRL and NT thickness were 12.5 (0.7) weeks, 60.2 (9.7) mm, and 1.15 (0.38) mm, respectively. The mean normal NT increased linearly with CRL. The quantile regression equation to predict the 95th percentile of the NT thickness (mm) was 0.727 + [0.017 × CRL (mm)]. Conclusions: The NT thickness in normal Thai fetuses was found to be thinner than in both Caucasian and other Asian populations.

Objective To evaluate the efficacy of the quadruple test for potential use as a Thai national policy for Down syndrome (DS) screening and establish an accurate equation for risk estimation of Down syndrome based on gestational age, weight and the ethnic-specific reference range of our population. Methods A prospective study was conducted on singleton pregnancies at 14 to 21 weeks of gestation to evaluate the efficacy of quadruple DS screening using the automatically calculated Western European descent factor (WF) in our population and the impact of screening using a specific Thai ethnic factor as well as to establish an equation for the risk estimation of DS based on gestational age, weight and a local Thai ethnic factor to correct for the impact of ethnic factor on the screening efficacy. Results Of a total of 5,515 women, 12 cases of DS and 8 cases of other aneuploidies were found. The detection rate, false positive rate and specificity were 75.0%, 9.1% and 90.9%, respectively, by automatic calculation with the widely used WF; the screening efficacy was lower when used in Asian populations than in other studies. The best-fitted regression equation of serum quadruple screening of AFP, free β-hCG, uE3 and inhibin A was established by adjustment for gestational age (GA) in days, maternal weight and our Thai-specific ethnic reference range which was created for this study. Calculations with our Thai-specific ethnic model gave a better detection rate of 83.3%, a false positive rate of 9.6% and specificity of 90.4%. Conclusion The serum quadruple test had a lower detection rate than expected when the risk estimation was based on the WF reference range. The serum quadruple test using WF had significantly different levels when corrected with our ethnic-specific factor. Using our local ethnic specific model could increase the detection rate of DS screening in Thailand with a minimal increase in false positive rates. Our findings indicate that DS screening should be adjusted with an appropriate individual ethnic factor when used for national screening.