Tuangsit Wataganara

Inverse correlation between maternal weight and second trimester circulating cell-free fetal DNA levels

OBJECTIVE: Clinical applications of the analysis of cell-free fetal DNA in maternal plasma and serum are expanding. However, use of fetal DNA during prenatal screening requires knowledge of variables that might affect its levels in the maternal circulation. We conducted this study to estimate the effect of selected demographic factors on fetal DNA levels in the first and second trimesters of pregnancy. METHODS: We developed a database that included fetal DNA levels and clinical information, such as maternal age, ethnicity, weight, and smoking history. We measured fetal DNA levels in maternal plasma and serum using real-time quantitative polymerase chain reaction amplification of a Y chromosome specific sequence. The fetal DNA data from fresh first trimester plasma and previously frozen second trimester serum samples were analyzed separately. Fetal DNA levels were adjusted according to gestational age and storage time and then analyzed in association with the demographic factors. RESULTS: In the first trimester group, no significant association between maternal age, weight, ethnic background, or smoking and plasma fetal DNA levels was observed. In the second trimester group, a significant inverse correlation between maternal weight and serum fetal DNA level was demonstrated (r = −0.26, P = .007). This was especially prominent when the mothers weighed more than 170 lb (P = .001). Maternal age, ethnicity, and smoking were not significantly associated with the second trimester serum fetal DNA levels. CONCLUSION: Fetal DNA levels are affected by maternal weight in the second trimester. A correction for this effect may be needed in larger-scale studies or for future clinical applications that measure cell-free fetal nucleic acids in maternal circulation. LEVEL OF EVIDENCE: II-3

Fetal nucleic acids in maternal body fluids: an update.

Abstract:  Our laboratory continues to be actively involved in the development of new biomarkers for prenatal diagnosis using maternal blood and amniotic fluid. We have also developed a mouse model that demonstrates that cell‐free fetal (cff) DNA is detectable in the pregnant maternal mouse. In human maternal plasma and serum we have analyzed factors that are important in the clinical interpretation of cff DNA levels. Maternal race, parity, and type of conception (natural or assisted) do not affect cff DNA levels, but maternal weight does. We have also analyzed the relationship between placental volume, using a three‐dimensionsal ultrasound examination, and cff DNA levels. Surprisingly, there is no association between these values. Finally, we are using specific disease models (such as congenital diaphragmatic hernia and twin‐to‐twin transfusion) to understand the effects of gestational age and specific pathology on fetal gene expression by analyzing cell‐free mRNA levels in maternal plasma. In the amniotic fluid we have focused on improvements in recovery of cff DNA and mRNA. By optimizing recovery we have made some interesting observations about differences in fetal DNA between blood and amniotic fluid. In addition, we have successfully hybridized cff DNA in amniotic fluid to DNA microarrays, permitting assessment of fetal molecular karyotype. We also have preliminary data on fetal gene expression in amniotic fluid. Finally, we remain actively involved in promoting noninvasive prenatal testing in the United States, such as encouraging the use of fetal DNA for fetal rhesus D assessment. On the other hand, we are cautious and concerned about the accuracy of “at‐home” kits for fetal gender detection.

Relation between gestational weight gain and pregnancy outcomes.

The aim of this study was to evaluate the effects of gestational weight gain on pregnancy outcomes in pregnant Thai women with different pre‐pregnancy body mass indexes (BMI).

Ultrasound in Africa: what can really be done?

Abstract Today we are living in a globalized world in which information on what is happening in one part of the world is easily communicated to other parts of the world. This happens thanks to advancement in science and technology. One area where technology has made the greatest impact is heath care provision. Ultrasound technology is now playing a critical role in health care provision particularly in Obstetrics and Gynaecology. This has significantly assisted in provision of quality health care to pregnant women and their unborn infants and in reducing maternal and neonatal morbidity and mortality in the developed world. Africa the continent with greatest health care challenges and with the highest maternal and neonatal mortalities is yet to fully utilize this important technology. The need for this technology is great as the conditions requiring its application abound. The effective application of Ultrasound however faces serious challenges in Africa. To successfully entrench Ultrasound in quality Obstetrics and Gynaecology care various approaches must be adopted to overcome the challenges. The aim of this paper is to identify the benefits and the challenges inimical to the application Ultrasound in Obstetrics and Gynecology in Africa. It also examines what needs to be done to achieve better application of Ultrasound in Obstetrics and Gynecology.

Maternal Vitamin D Status and Its Related Factors in Pregnant Women in Bangkok, Thailand.

Background There are few data focusing on the prevalence of vitamin D deficiency in tropical countries. Objectives We determined the vitamin D status in pregnant women and examined the factors associated with vitamin D deficiency. Design and Methods A cross-sectional study of 147 pregnant Thai women aged 18–45 years at Siriraj Hospital (a university hospital in Bangkok, Thailand) was undertaken. Clinical data and plasma levels of 25-hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH), calcium, albumin, phosphate and magnesium were obtained in pregnant women at delivery. Results The prevalence of hypovitaminosis D [defined as 25(OH)D <75 nmol/L] in pregnant women at delivery was 75.5% (95% confidence interval (CI), 67.7–82.2%). Of these, vitamin D insufficiency [defined as 25(OH)D 50–74.9 nmol/L] was found in 41.5% (95% CI, 33.4–49.9%) and vitamin D deficiency [25(OH)D <50 nmol/L] was found in 34.0% (95% CI, 26.4–42.3%) of women. The mean 25(OH)D concentration was 61.6±19.3 nmol/L. The correlation between 25(OH)D and iPTH was weak (r = –0.29, P<0.01). Factors associated with vitamin D deficiency by multiple logistic regression were: pre-pregnancy body mass index (BMI in kg/m2, odds ratio (OR), 0.88, 95% CI 0.80–0.97, P = 0.01) and season of blood collection (winter vs. rainy, OR, 2.62, 95% CI 1.18–5.85, P = 0.02). Conclusions Vitamin D deficiency is common among pregnant Thai women. The prevalence of vitamin D deficiency increased in women who had a lower pre-pregnancy BMI and whose blood was collected in the winter. Vitamin D supplementation may need to be implemented as routine antenatal care.

Maternal and neonatal outcomes in women with severe pre-eclampsia undergoing cesarean section: a 10-year retrospective study from a single tertiary care center: anesthetic point of view.

Abstract Objective: This study is aiming to determine an actual incidence and characteristics of complications in cesarean section for severe pre-eclampsia (PE) by analysis of a large cohort from a single tertiary care center according to two choices of anesthesia. Methods: Electronic medical records of pregnant women complicated with severe PE delivered by cesarean section from January 2002 to December 2011 were retrospectively reviewed. Medical records of their corresponding neonates were also identified and reviewed. Results: A total of 701 women and 740 neonates (28 twin pairs) were identified. Anesthetic techniques were spinal anesthesia (SA) (88%) and general anesthesia (GA) (12%). Total maternal and neonatal deaths were 0.3% and 1.2%, respectively. Patients in GA group had a higher incidence of coagulopathy, immediate postpartum hemorrhage, intensive care unit admission, renal failure, respiratory complications, and death (p < 0.05). Neonates born from women in GA group had a higher incidence of lower birth weight, birth asphyxia, prematurity, neonatal intensive care admission, respiratory complications, and death (p < 0.05). Conclusion: Spinal anesthesia can be safely administered to severely pre-eclamptic parturients undergoing cesarean section. General anesthesia is associated with more untoward outcomes, as it has been chosen in patients with more severity of the disease.

Three‐dimensional power Doppler in the diagnosis and surgical management of thoraco‐omphalopagus conjoined twins

We report the case of a 28-year-old primigravida in whom we diagnosed thoraco-omphalopagus conjoined twins at 23 weeks’ gestation. Further examination revealed a shared liver and separate gall bladders. The twins shared a single umbilical cord. This raised the possibility of sharing of the major intrahepatic vasculature, which could preclude surgical separation. Three-dimensional (3D) power Doppler examination of the hepatic and funic vasculatures was performed using a Voluson ultrasound machine (GE Healthcare Technologies, Milwaukee, WI, USA), equipped with a 3.5-MHz automatic-sweeping transabdominal E8 transducer (Figure 1). This revealed a single three-vessel umbilical cord. The umbilical vein bifurcated into each fetus’s hepatic vein, as shown in Figure 2. No major vascular anastomoses were found between the livers of each twin. After extensive counseling, the couple opted for continuation of pregnancy, followed by Cesarean section at 36 weeks’ gestation. Postnatal magnetic resonance imaging (MRI) revealed no major shared intrahepatic vasculature. After a tissue expansion procedure, surgical separation was performed successfully at 8 months of age without immediate serious damage to either twin. No major intrahepatic vascular anastomoses were found intraoperatively. The chance of successful postnatal separation of conjoined twins depends on the complexity of vital organ fusion1. For omphalopagus twins, the degree of

Reverse Twin-Twin Transfusion Syndrome after Fetoscopic Laser Photocoagulation of Chorionic Anastomoses: A Case Report

A case of severe twin-twin transfusion syndrome (TTTS) which developed at menstrual age of 17 weeks underwent a fetoscopic laser ablation of the anastomosing vessels. The vascular equator of the anastomoses was noticed to be deviated due to marginal cord insertion of the recipient fetus. The procedure was accomplished uneventfully. However, the recipient fetus died 6 h after the procedure. After the pregnancy was terminated, the donor was found to be counterintuitively plethoric, and the recipient was pale. Similar appearances were noted on the placental territories of each fetus. This is consistent with reverse TTTS. Dye injection study and microscopic examination revealed a residual deep vein-vein anastomosis. This subchorionic vascular connection is still a challenge to coagulate with current placental surgery techniques. To the best of our knowledge, this is the first confirmed case of reverse TTTS as a cause of fetal loss following laser photocoagulation. This report also discusses the technical considerations in the complicated case of in utero placental surgery for TTTS.

Delivery modes in case of fetal malformations.

Abstract An estimated 276,000 babies die within 4 weeks of birth every year, worldwide, from congenital anomalies. Better quality ultrasound screening can increase the detection of these fetal malformations in the prenatal period. Prenatal counseling for the pregnant woman and her family, regarding the nature of the disease and prognosis is necessary. Options for management in prenatal, perinatal, intrapartum, neonatal, and childhood periods need to be thoroughly discussed, so that the family can make an informed decision. A multidisciplinary approach is usually needed once a decision has been made to optimize fetal outcome, to plan for the timing and location as well as the mode of delivery. In most of the cases, vaginal delivery can be attempted. An elective cesarean delivery should be reserved for maternal concern of dystocia, certain fetal conditions that cesarean delivery will optimize perinatal outcome, or if the parents have a psychosocial determination to have a live-born infant.

Circulating free soluble fms-like tyrosine kinase-1 during late first trimester in relation with placental volume as a surrogate for trophoblastic production: a physiology study in low-risk cohort

Abstract Background: Data on first-trimester circulating soluble fms-like tyrosine kinase-1 (sFlt-1) and ischemic placental disease is limited and conflicting. This study aimed to study its physiology in relation to trophoblastic mass as the source of production. Methods: Low-risk (representing normal placentation) women from 11 0/7 to 13 6/7 weeks’ gestation were prospectively enrolled. Selective measurement of serum free sFlt-1 using a new automated assay from 100 eligible subjects was analyzed with gestational age, maternal weight, fetal crown-rump length (CRL), and mean uterine artery Doppler pulsatility index (PI). Placental volume (surrogate for trophoblastic mass) was estimated using 3-dimensional ultrasound and was assessed for its association with serum free sFlt-1. Results: There was no significant association between serum free sFlt-1 and placental volume in either arithmetic (r = 0.053, p = 0.600), logarithmic (r = 0.005, p = 0.963), or quartile (p = 0.703) scale. There was a significant negative correlation between free sFlt-1 level and maternal weight (r=−0.213, p = 0.033). No significant correlation was found between free sFlt-1 level and gestational age (r = 0.007, p = 0.947), CRL (r = 0.027, p = 0.788), and uterine artery Doppler mean PI (r = 0.020, p = 0.828). Conclusions: Lack of correlation between circulating free sFlt-1 level and placental volume suggests that trophoblasts are not its major source during first trimester with presumably physiologic placentation.