Changes in fetal cardiac axis between 8 and 15 weeks' gestation

OBJECTIVES

To document changes in the normal embryonic/fetal cardiac axis in the late first and early second trimesters of pregnancy.

METHODS

Images from 188 fetal echocardiograms performed prospectively between 8 and 15 weeks' gestation in 166 healthy pregnancies and in 10 pregnancies with severe fetal heart disease were reviewed. For each echocardiogram, three measurements of the cardiac axis were taken in the axial plane at the level of the four-chamber view. Differences in mean embryonic/fetal cardiac axis at different gestational ages in the healthy pregnancies were compared.

RESULTS

The mean ± SD embryonic/fetal cardiac axis was 25.5 ± 11.5° from 8 + 0 to 9 + 6 weeks (Group  1), 40.4 ± 9.2° from 10 + 0 to 11 + 6 weeks (Group  2), 49.2 ± 7.4° from 12 + 0 to 12 + 6 weeks (Group  3), 50.6 ± 5.7° from 13 + 0 to 13 + 6 weeks (Group 4) and 48.6 ± 7.3° from 14 + 0 to 14 + 6 weeks (Group 5). Groups 1 and 2 were significantly different from each other and all other groups (P < 0.05). The results for 22 cases with repeat measurements from 8 + 0 to 11 + 6 and 12 + 0 to 14 + 6 weeks confirmed that the embryonic/fetal cardiac axis increased significantly (P < 0.001). In the cases with severe congenital heart disease, the cardiac axis was > 90th centile in four cases and < 10th centile in two cases.

CONCLUSIONS

The embryonic cardiac axis is relatively midline at 8 weeks and levorotates in the late first trimester. By 12 weeks' gestation, the normal leftward fetal cardiac axis is established and remains stable until at least 14 + 6 weeks. Observation of an abnormal cardiac axis in some cases of severe congenital heart disease prior to 15 weeks' gestation may assist in prenatal detection.

Prevalence of obesity among Bangladeshi pregnant women at their first trimester of pregnancy

BACKGROUND

Paradoxically, the escalating global epidemic of maternal obesity coexists with malnutrion in many areas of Bangladesh. This proves a major challenge to obstetric practice from preconception to postpartum due to related comorbid conditions including: maternal death or severe morbidity, gestational diabetes and hypertension, increased risk of early and recurrent miscarriage, pre-eclampsia, thromboembolism, post-caesarean wound infection, postpartum haemorrhage, and low breastfeeding rates. A dramatic increase in birth defects and other pregnancy-induced disorders related to maternal obesity has added millions of dollars to health care costs leading great economical loss to the country.

OBJECTIVE

The study was designed to determine the prevalence of obesity among Bangladeshi pregnant women in their 1st trimester of pregnancy.

STUDY DESIGN

426 pregnant women presenting to the antenatal care until of Azimpur maternity hospital of Dhaka, Bangladesh were randomly selected for this cross sectional study to determine their weight status using body mass index (BMI, kg/m2).

RESULT

90 (21.2%) pregnant women were reported as obese with pregnancy BMI of >30 kg/m2. 171 (40.1%) and 140 (32.8%) pregnant women were reported as overweight and healthy with pregnancy BMI of 25-29.9 kg/m2 and 18.5-24.9 kg/ m2, respectively. Statistical analysis revealed obesity and overweight status were found to be significantly associated with age; women aged 31 or above were more likely to be obese (OR=2.5; 95% CI 1.53-3.96) and overweight (OR=3.3; 95% CI 2.15-4.99).

CONCLUSION

This study provides evidence of increasing trends in obesity among Bangladeshi pregnant women, which poses possible health risks both for mother and child. The findings of this study may act as baseline data for monitoring the effectiveness of national programs for the prevention and control of maternal obesity.

First-trimester uterine artery Doppler examination in pregnancies complicated by gestational diabetes mellitus with or without pre-eclampsia

OBJECTIVES

To assess first-trimester placental perfusion, reflected in the uterine artery (UtA) pulsatility index (PI), in pregnancies complicated by gestational diabetes mellitus (GDM), with or without pre-eclampsia (PE), compared with those unaffected by GDM.

METHODS

UtA-PI was measured at 11 + 0 to 13 + 6 weeks' gestation in 1037 singleton pregnancies that subsequently developed GDM and in 56 649 normoglycemic controls. The measured mean UtA-PI was converted to multiples of the expected normal median (MoM), corrected for maternal weight, racial origin and gestational age, and the median MoM values in the two groups were compared.

RESULTS

The incidence of PE was higher in pregnancies with GDM than in controls (4.0% vs 2.3%, respectively; P =  0.001). However, there were no significant differences in the median UtA-PI MoM between the groups (1.00 (interquartile range (IQR), 0.82-1.21) vs 1.00 (IQR, 0.81-1.21); P = 0.73). The median UtA-PI in patients who developed PE was higher than in those who did not develop PE, regardless of the development of GDM.

CONCLUSIONS

First-trimester placental perfusion, as assessed by UtA Doppler examination, is not impaired in women who subsequently develop GDM. The increased prevalence of PE in women with GDM cannot be attributed to impaired placentation.

Periconception maternal characteristics and embryonic growth trajectories: the Rotterdam Predict study

STUDY QUESTION

Are maternal characteristics and lifestyle factors associated with human embryonic growth trajectories?

SUMMARY ANSWER

Periconception maternal age is associated with increased, and smoking and alcohol use with decreased embryonic growth trajectories, estimated with crown-rump length (CRL) measurements.

WHAT IS KNOWN ALREADY

Fetal weight is associated with health and disease in later life. Maternal characteristics and lifestyle factors affect fetal growth in the second and third trimesters of pregnancy and at birth; however, little is known about the association of these characteristics with first trimester embryonic growth.

STUDY DESIGN, SIZE, DURATION

In a tertiary centre, pregnant women were recruited and enrolled in a prospective periconception cohort study before 8 weeks of gestation. We selected 87 spontaneously conceived singleton pregnancies of women recruited in 2009 and 2010 that ended in non-malformed live births.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We performed weekly three-dimensional ultrasound scans from enrolment up to 13 weeks of gestation. At enrolment, a questionnaire was completed. Embryonic CRL measurements were performed using the V-Scope software in the BARCO I-Space. Associations between maternal characteristics and embryonic growth were assessed using square root transformed CRL as response in linear mixed model analyses, adjusted for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

Four hundred and ninety-six scans from 87 pregnancies were included. In the multivariable analysis, maternal age was positively associated with first trimester CRL (difference per maternal year of age 0.024√mm (95% confidence interval (CI) 0.009, 0.040), P = 0.001). At 6 and 12 weeks of gestation, the CRL of an embryo from a 40-year-old mother was estimated 2.0 mm (61%) and 7.2 mm (14%) larger, respectively, compared with an embryo from a 20-year-old mother. Smoking of 10 or more cigarettes per day was negatively associated with CRL (difference -0.211√mm (95% CI -0.416, -0.006), P = 0.04), with embryos that were 0.9 mm (18.7%) and 3.1 mm (5.5%) smaller at 6 and 12 weeks, respectively, compared with non-smokers. Periconception alcohol use was negatively associated with CRL growth rate (difference -0.0025√mm (95% CI -0.0047, -0.0003)/day gestational age, P = 0.022), with embryos that were 0.2 mm (3%) and 1.1 mm (2%) smaller at 6 and 12 weeks, respectively, compared with non-alcohol users. Parity, BMI and moment of initiation of folic acid use were not significantly associated with embryonic CRL.

LIMITATIONS, REASONS FOR CAUTION

Due to the selection of pregnancies in a tertiary centre and the small number of pregnancies, the external validity of the results has to be confirmed using larger sample sizes and other population-based periconception cohort studies.

WIDER IMPLICATIONS OF THE FINDINGS

The association of maternal age and smoking with embryonic growth is in line with previous literature, whereas the association between embryonic growth and alcohol use is a new finding. However, concerning exposure to alcohol, the effect estimate was small and it is questionable whether this is of clinical value. More research is warranted to unravel underlying mechanisms and to assess the implications for preconception and early pregnancy care, such as the development and implementation of effective lifestyle interventions.

STUDY FUNDING/COMPETING INTEREST(S)

The work was funded by the Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. The authors declare no conflicts of interest.

Screening for fetal spina bifida at the 11-13-week scan using three anatomical features of the posterior brain

OBJECTIVE

To evaluate the contribution of examination of specific anatomical features of the fetal posterior brain on mid-sagittal first-trimester ultrasound examination to the early detection of open spina bifida.

METHODS

Four independent observers reviewed a series of 260 mid-sagittal first-trimester ultrasound images from 52 cases of open spina bifida and 208 normal fetuses. The following analysis was performed by each reviewer for each image: Herman score calculation, intracranial translucency score (CFEF-IT) calculation and determination of presence or absence of three anatomical criteria: intracranial translucency (IT), caudal displacement of the brainstem and cisterna magna. The sensitivity and the false-positive rate for spina bifida detection were calculated for each of the latter three criteria. A secondary analysis was performed on the subset of images achieving a Herman score ≥ 7.

RESULTS

The highest detection rate for spina bifida was achieved by non-visualization of the cisterna magna, with associated sensitivity of 50-73% and 39-76%, respectively, for all images and for the subset of images achieving a Herman score ≥ 7. Posterior shift of the brainstem achieved the highest detection rate (86%), but for a single reviewer only. The level of variation in performance between observers was also greatest for this sign. Absence of IT was associated with a lower detection rate for all observers. Overall, an abnormal posterior brain presenting at least one of these three criteria was associated with a detection rate ranging from 50 to 90%.

CONCLUSION

In the detection of spina bifida, non-visualization of the cisterna magna achieved the best screening performance. Both non-visualization of the IT and posterior shift of the brainstem were associated with acceptable but lower detection rates. A prospective evaluation of changes in the posterior brain is needed to allow assessment of the most pertinent criteria for first-trimester screening for spina bifida.

Biparietal diameter at 11-13 weeks' gestation in fetuses with open spina bifida

OBJECTIVE

To ascertain the reported association between reduced biparietal diameter (BPD) at 11-13 weeks' gestation and open spina bifida and to investigate its predictive value in a single-center study.

METHODS

This was a retrospective study of fetuses in which BPD was measured at 11-13 weeks' gestation, including 27 fetuses with isolated open spina bifida subsequently diagnosed at 16-24 weeks and 7775 unaffected controls. BPD values were converted into multiples of the expected median (MoM) after adjustment for crown-rump length and maternal characteristics. Multivariable logistic regression analysis was used to determine the maternal characteristics significantly associated with spina bifida. The performance of screening was determined by receiver-operating characteristics curve analysis. BPD values at 11-13 weeks' gestation were compared with those measured in the second trimester using Z-scores.

RESULTS

BPD values at 11-13 weeks' gestation were below the 5(th) centile in 44.4% of cases of open spina bifida. In these fetuses, the median BPD MoM value was significantly smaller than that in the control group (0.930 vs 0.998 MoM; P < 0.0001). Multivariable logistic regression analysis showed a significant contribution from maternal age (P = 0.008) and BMI (P = 0.028) to the association between BPD MoM and spina bifida. The detection rate using BPD measurements in the first trimester was 55.6% with a false-positive rate of 11.6%. In fetuses with open spina bifida, the BPD Z-scores were significantly lower at 16-24 weeks compared to those recorded at 11-13 weeks (median, -1.71 (range, -3.98 to -0.20) vs -1.30 (-3.75 to 2.61); P = 0.006).

CONCLUSION

Fetuses with open spina bifida have a smaller BPD in the first trimester. This observation may be useful in early screening. It is likely that a combination of maternal characteristics such as age and BMI, fetal BPD and maternal serum alpha-fetoprotein measured in the first trimester would provide a clinically useful screening test for open spina bifida.

Reference values for the right and left fetal choroid plexus at 11 to 13 weeks: an early sign of "developmental" laterality?

OBJECTIVES

The purpose of this study was to establish reference values for the length, area, and circumference of the right and left fetal choroid plexus at 11 to 13 weeks with respect to the fetal biparietal diameter and to compare the right to the left side.

METHODS

We conducted a prospective study on 114 fetuses at 11 to 13 weeks undergoing first-trimester screening for aneuploidy and structural fetal abnormalities. After the establishment of the fetal situs, the plane of the "butterfly" was obtained on all fetuses, from which the length, area, and circumference of both the right and left choroid plexus were obtained and the right and left sides compared. Using a paired t test, analysis of variance, scatterplots, and linear and logarithmic fittings, reference ranges and charts for the length, area, and circumference of the choroid plexus were then formulated according to their relationship to the fetal biparietal diameter. P < .05 was considered statistically significant.

RESULTS

Reference values for the length, area, and circumference of the fetal choroid plexus, with respect to the fetal biparietal diameter, were established. There was a statistically significant difference between the right and left sides for all parameters, with all measurements statistically greater on the left side (P < .0001).

CONCLUSIONS

Reference values for the length, area, and circumference of the fetal choroid plexus at 11 to 13 weeks are presented. These may prove to be of clinical importance in the early screening for central nervous system abnormalities. In addition, the statistically significant difference between the right and left sides may be an early sign of "developmental" laterality.

Combined screening for open spina bifida at 11-13 weeks using fetal biparietal diameter and maternal serum markers

OBJECTIVE

Screening at 11-13 weeks with ultrasound biparietal diameter (BPD) can detect half of open spina bifida cases. Maternal serum α-fetoprotein (AFP) levels at 15-19 weeks are increased 3- to 4-fold, in open spina bifida. We assessed whether combined screening using BPD, AFP, and other serum markers at 11-13 weeks would increase detection.

STUDY DESIGN

Maternal AFP levels were measured on serum stored at 11-13 weeks in 44 open spina bifida and 182 unaffected pregnancies, and results were expressed in multiples of the median (MoM) for gestational age. All samples had been measured for free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein (PAPP)-A. A multivariate Gaussian model was used to predict screening performance from the serum data and BPD measurements on 80 cases, including 36 previously published.

RESULTS

The median AFP level in cases was 1.201 MoM, significantly higher than in unaffected pregnancies (P < .01, 1 tail). The median free β-hCG was significantly reduced to 0.820 MoM (P < .02), but the median PAPP-A was similar in cases and controls. Modeling predicted the following: BPD alone would detect 50% of cases for a 5% false-positive rate or 63% for 10%; adding AFP increases detection by 2%; and a combined test with BPD, AFP, and free β-hCG detects 58% for 5% or 70% for 10%.

CONCLUSION

Combining AFP and BPD with free β-hCG as part of first-trimester aneuploidy screening would also allow early detection about two-thirds of cases with open spina bifida.

Improved detection rate of structural abnormalities in the first trimester using an extended examination protocol

OBJECTIVE

To assess the potential of first-trimester sonography in the detection of fetal abnormalities using an extended protocol that is achievable with reasonable resources of time, personnel and ultrasound equipment.

METHODS

This was a prospective two-center 2-year study of 5472 consecutive unselected pregnant women examined at 12 to 13 + 6 gestational weeks. Women were examined using an extended morphogenetic ultrasound protocol that, in addition to the basic evaluation, involved a color Doppler cardiac sweep and identification of early contingent markers for major abnormalities.

RESULTS

The prevalence of lethal and severe malformations was 1.39%. The first-trimester scan identified 40.6% of the cases detected overall and 76.3% of major structural defects. The first-trimester detection rate (DR) for major congenital heart disease (either isolated or associated with extracardiac abnormalities) was 90% and that for major central nervous system anomalies was 69.5%. In fetuses with increased nuchal translucency (NT), the first-trimester DR for major anomalies was 96%, and in fetuses with normal NT it was 66.7%. Most (67.1%) cases with major abnormalities presented with normal NT.

CONCLUSIONS

A detailed first-trimester anomaly scan using an extended protocol is an efficient screening method to detect major fetal structural abnormalities in low-risk pregnancies. It is feasible at 12 to 13 + 6 weeks with ultrasound equipment and personnel already used for routine first-trimester screening. Rate of detection of severe malformations is greater in early- than in mid-pregnancy and on postnatal evaluation. Early heart investigation could be improved by an extended protocol involving use of color Doppler.

Reference ranges and distribution of placental volume by 3-dimensional virtual organ computer-aided analysis between 11 weeks and 13 weeks 6 days

OBJECTIVES

The purpose of this study was to determine the feasibility, reproducibility, and distribution of placental volume measurements according to the crown-rump length between 11 weeks and 13 weeks 6 days.

METHODS

Images were acquired in 128 pregnancies followed in Burgundy during first-trimester screening sonography using an abdominal 3-dimensional transducer. The placental volume was then calculated by the virtual organ computer-aided analysis method with a rotation angle of 30° by a single operator.

RESULTS

Placental volumes ranged from 33.3 to 107.6 cm(3) with a mean ± SD of 62.3 ± 14.8 cm(3); the 5th and 10th percentiles were 38.0 and 44.20 cm(3), respectively, whereas the 90th and 95th percentiles were 80.25 and 86.68 cm(3). An exponential relationship was found between placental volume and crown-rump length: ln placental volume = 0.018 × crown-rump length + 2.93425; ln SD = 0.15; r(2) = 0.58. Finally, the mean placental quotient, defined as the ratio of placental volume to crown-rump length, was 1 ± 0.1 cm(3)/mm; the respective percentile values were 0.74, 0.81, 1.18, and 1.29 cm(3)/mm. No associations were found between parity or smoking and the placental quotient or between obesity and the placental quotient. Intraobserver reproducibility was good, with a mean difference of 0.2 cm(3).

CONCLUSIONS

Measurement of placental volume between 11 weeks and 13 weeks 6 days is reliable and reproducible and correlates strongly with crown-rump length.

Shifts in color discrimination during early pregnancy

The present study explores two hypotheses: a) women during early pregnancy should experience increased color discrimination ability, and b) women during early pregnancy should experience shifts in subjective preference away from images of foods that appear either unripe or spoiled. Both of these hypotheses derive from an adaptive view of pregnancy sickness that proposes the function of pregnancy sickness is to decrease the likelihood of ingestion of foods with toxins or teratogens. Changes to color discrimination could be part of a network of perceptual and physiological defenses (e.g., changes to olfaction, nausea, vomiting) that support such a function. Participants included 13 pregnant women and 18 non-pregnant women. Pregnant women scored significantly higher than non-pregnant controls on the Farnsworth-Munsell (FM) 100 Hue Test, an objective test of color discrimination, although no difference was found between groups in preferences for food images at different stages of ripeness or spoilage. These results are the first indication that changes to color discrimination may occur during early pregnancy, and is consistent with the view that pregnancy sickness may function as an adaptive defense mechanism.

Placenta percreta-induced uterine rupture diagnosed by laparoscopy in the first trimester

Spontaneous uterine rupture is lethal in pregnant women. Placenta percreta-induced spontaneous uterine rupture in the first trimester is extremely rare and difficult to diagnose. A 35-year-old pregnant woman, with a history of 2 vaginal deliveries and 2 spontaneous abortions treated by dilatation and curettage, was admitted to the emergency department because of sudden severe abdominal pain; the gestational age as calculated by sonography was 14 weeks. Diagnostic laparoscopy was considered for surgical abdomen and fluid collection that was noted in sonography. During laparoscopy, uterine rupture with massive bleeding was detected; therefore, total abdominal hysterectomy was performed. The patient was discharged without any complications. Pathological analysis of the uterine specimen revealed placenta percreta to be the cause of the rupture. Uterine rupture should be considered in the differential diagnosis in all pregnant women who present with acute abdomen, show fluid collection in the peritoneal cavity. In addition, we recommend laparoscopy for the investigation of acute abdomen with unclear diagnosis in the first trimester of pregnancy.

Dichlorodiphenyldichloroethylene exposure during the first trimester of pregnancy alters the anal position in male infants

Anogenital distance (AGD) at birth is regarded as a useful measurement that reflects the prenatal androgenic status in rodents. However, the impact of xenoantiandrogens on human development is largely unknown. The aim of this study was to evaluate the potential antiandrogenic impact of prenatal DDT metabolites (p,p'-DDE and p,p'-DDT) exposure on infant AGD, using a non-age-dependent anal position index (API). As part of an ongoing perinatal cohort study on the effects of organochlorine pesticides in children's neurodevelopment, we conducted a cross-sectional study in 71 infants (37 males and 34 females). Maternal serum levels of DDT metabolites (p,p'-DDE and p,p'-DDT) before and during each trimester of pregnancy were determined by electron capture gas-liquid chromatography. During postnatal home visits at 3, 6, and 12 or 18 months of age, the children's weight and API were evaluated. Multiple lineal regression models were used to estimate the potential endocrine disruptor activity of prenatal p,p'-DDE exposure. Boys had significantly higher API values than girls (0.6 versus 0.5; P < 0.001). Only among boys, a doubling increase of maternal p,p'-DDE serum levels during the first trimester of pregnancy, were associated with a significant reduction of API (beta=-0.02; P= 0.02). No effect of p,p'-DDT on AGD was observed. Evidence of the effect of prenatal p,p'-DDE on external genital differentiation is scarce and not consistent in the literature. Further studies are needed to confirm a hormonal disruptive effect on the development of external genitalia, due not only to p,p'-DDE but also due to other antiandrogenic persistent compounds.

A case of placenta increta presenting as delayed postabortal intraperitoneal bleeding in the first trimester

Placenta increta is an uncommon and life-threatening complication of pregnancy characterized by complete or partial absence of the decidua basalis. Placenta increta usually presents with vaginal bleeding during difficult placental removal in the third-trimester. Although placenta increta may complicate first and early second-trimester pregnancy loss, the diagnosis can be very difficult during early pregnancy and thus the lesion is difficult to identify. We encountered with a woman who was diagnosed with placenta increta after receiving emergency hysterectomy due to intraperitoneal bleeding 2 months after an uncomplicated dilatation and curettage in the first trimester. Therefore, we report this case with a brief review of the literature.

Capacity for hormone production of cultured trophoblast cells obtained from placentae at term and in early pregnancy

PROBLEM

There is an increased doubt about the identity of isolated cytotrophoblast cells at term. Therefore, we compared pregnancy serum levels of three hormones [human placental lactogen (hPL), human chorionic gonadotropin (hCG), and leptin] with the capacity for hormone production of early placentae [EP; 8-13 weeks of gestation (WG)] and term placentae (TP; 38-42 WG).

METHODS

Serum levels of these hormones were determined in 15 paired maternal (7-41 WG) and fetal (37-41 WG) samples. Cytotrophoblast cells were isolated from term (TP; 38-42 weeks) and early (EP; 8-13 weeks) placentae by enzymatic digestion and subsequent purification on a Percoll gradient. These cells were cultured for 6 days. The production of the hormones hPL, hCG, and leptin was determined as release during culture + cell content after culture - cell content before culture.

RESULTS

Serum levels (mean +/- SD; n = 15) at 7-12 and 37-41 WG were 89,652 +/- 21,431 and 13,620 +/- 5854 mIU/ml for hCG, 400 +/- 182 and 7088 +/- 2030 ng/ml for hPL, and 12,675 +/- 4266 and 32,236 +/- 10,961 pg/ml for leptin, respectively. For cultured cells from EP and TP, hCG and hPL showed different patterns of release during the first 2-3 days. While the release of these two hormones by EP cytotrophoblast cells continued during 6 days in culture, their concentrations reached a plateau for TP cytotrophoblasts between 4 and 6 days. Leptin was undetectable (< 15 pg/ml) in TP cell cultured media, while for EP all three hormones showed the same release profiles. Production calculated for 30,000 TP trophoblast cells cultured for 6 days (n = 8) was 2-31 mIU for hCG and 0.5-2 ng for hPL. For EP (n = 11), it was 50-1070 mIU for hCG, 15-323 ng for hPL, and 137-580 pg for leptin. Net synthesis of hCG and hPL for TP was > 10-fold and < 1-fold, respectively. In contrast, the production of all three hormones for EP was at least 100 times the initial cell content.

CONCLUSIONS

These results demonstrate that trophoblasts from early pregnancy show much higher production rates of hCG, hPL, and leptin than at term. However, the in vitro findings are difficult to be reconciled with the different serum concentrations of the two hormones hPL and leptin observed during the course of pregnancy.