Cribado cromosómico del primer trimestre. Resultados en gestaciones tras reproducción asistida

Objective

To determine the effectiveness of the combined test for aneuploidies in the first trimester of spontaneous pregnancies in comparison with pregnancies following assisted reproductive technology (ART).

Materials and methods

We performed a retrospective study of 1675 triple tests performed in the first trimester in our center, including pregnancy-associated plasma-A (PAPP-A) and the free fraction of the β subunit of human chorionic gonadotropin (free β-hCG), maternal age and nuchal scan. Of these, 1299 (77.5%) were spontaneous pregnancies and 376 (22.5%) were pregnancies following ART. The cut-off point for recommending an invasive test was 1/270.

Results

The combined test was carried out in 74 twin pregnancies, with two false-positive results. Among single pregnancies, 70 positive triple tests were obtained, 3.79% of spontaneous pregnancies and 6.84% of ART pregnancies. Eleven chromosomal abnormalities were found, nine in spontaneous pregnancies and two in ART pregnancies. The sensitivity of the test was 89% in spontaneous pregnancies and 100% in ART pregnancies. The specificity was 96% and 93.77%, respectively.

Conclusions

The first trimester triple test has high sensitivity and specificity in single pregnancies, whether spontaneous or following ART. The rate of positive triple tests is higher in pregnancies following ART.     

Cribado combinado de síndrome de Down en primer trimestre: comparación de resultados de 4 años de aplicación con los 4 años precedentes

Objective

To analyze the 4-year results of first-trimester combined screening and its impact on rates of Down syndrome detection, population coverage and invasive procedures.

Subjects and methods

We performed a retrospective population-based study over 8 consecutive years (17,564 gestations with 51 cases of Down syndrome) divided in two periods: from January 31, 2002 to January 30, 2006 without combined screening (8,182 gestations and 24 cases of Down syndrome) and from January 31, 2006 to January 30, 2010 with combined screening (8,382 gestations and 27 cases of Down syndrome). Combined screening was applied in two phases: biochemical analysis was performed in the 10th week of pregnancy and ultrasound examination in the 12th week. We compared the results of screening with the previous period based on maternal age and fetal nuchal translucency measurement.

Results

Population coverage was 93%. The rate of Down syndrome detection due to the application of combined screening was 89% (91% for a single fetus) with a false-positive rate of 3.5%. There were 824 invasive procedures (34.1 to diagnose one episode). During the 4 years prior to the application of combined screening, the detection rate was 71% with 1,406 invasive procedures (87.8 to diagnose one episode).

Conclusion

Combined screening has improved the Down syndrome detection rate by 18% and has reduced the use of invasive procedures by 41%.     

Cribado combinado del síndrome de Down: validación del riesgo estimado por Fetaltest

Objective

To validate empirically the risk for Down syndrome estimated by Fetaltest using biochemical markers in the first trimester (PAPP-A and free beta subunit of hCG) and nuchal translucency.

Material and methods

We performed a retrospective study of the data from 15,009 pregnant women screened for Down Syndrome in the first trimester, included in the database prospectively maintained by the Fetaltest multicenter study, and completed before December 31, 2007. The study included 39 cases of Down syndrome detected either prenatally or postnatally, and used a previously established analysis method.

Results

The correlation between predicted risk and the observed prevalence of Down syndrome was very high (r = 0.999967).

Conclusions

The risk estimated by Fetaltest agrees closely with the observed prevalence of Down syndrome. Therefore, this calculation system is valid and can be used with confidence when counseling pregnant women in our environment.     

Impacto de la introducción en el primer trimestre del cribado combinado de trisomía 21 en la tasa de procedimientos invasivos

Objective

To study the impact of introducing first-trimester combined Down syndrome screening on invasive prenatal testing for prenatal diagnosis, together with the criteria change from 35 to 38 years old as the indication for obtaining the fetal karyotype.

Material and methods

A retrospective population-based study was carried out of invasive tests for prenatal diagnosis performed at the Cabueñes Hospital in Gijón (Spain). A first period from 31-1-2004 to 30-1-2006 (without the screening program) was compared with a second period from 31-1-2006 to 30-1-2008 (with the screening program). During the second period the impact of screening (31-1-2006 to 30-1-2007) was differentiated from that linked to changing the maternal age criteria to 38 years old as the indication for invasive testing (31-1-2007 to 30-1-2008).

Results

During the second period there was an overall reduction of 31.2% in invasive testing; 21.6% was exclusively attributable to first-trimester combined Down syndrome screening. In expectant mothers aged 35 or more at delivery, the number of amniocentesis performed in the second period was reduced by 30.74%; this tendency was maintained for pregnant women aged 38 years or more, showing a reduction of 25.92%. In the second period, 30% of the expectant mothers aged 38 years or more chose to have an invasive test due to their age compared with 61.53% in the first period.

Conclusions

First-trimester combined Down syndrome screening had a major impact on invasive testing, increasing its efficiency and, moreover, allowing detection rates to be improved.     

Entrecruzamiento de cordones en la gestación gemelar monocorial monoamniótica

Monochorial monoamniotic twins are at high risk of fetal death due to the general complications seen in multiple gestations, as well as those specific to this type of pregnancy. The most severe complication in these pregnancies is fetal death due to cord entanglement, which occurs in almost all cases.Early ultrasonographic diagnosis and intensive prenatal surveillance are essential for the early detection of cord entanglement and the prevention of fetal death.The need for in-hospital management and the exact gestational age for delivery continue to generate controversy in the literature.     

Feto acardio en gestación gemelar monocorial biamniótica. Síndrome de perfusión arterial inversa gemelar

Multiple gestations involve an exacerbation of the signs and own symptoms of the pregnancy, and suppose a situation of risk for the mother as for the fetuses.One of these complications is the twin reverse arterial perfusion (TRAP), a very rare process (1% of the multiple gestations) or 0,3/10000 borned alive, that consists of the coexistence of a normal fetus (called “pump”) and an acardiac fetus.The abnormal fetus, displays, in most of the cases, incomplete development of the cephalic pole, heart, superior members and numerous organs. The lower members are relatively well conserved although the foot is usually bad conformed as well as the anomalies in the toes are frequent. Is frequent the edema in superior half of the fetus.We displayed an agreed case about this matter occurred in our hospital.     

Resultados obstétricos en cribado combinado de las aneuploidías en el primer trimestre superior al corte con resultado de amniocentesis con cariotipo fetal normal

Introduction

To evaluate whether there are adverse pregnancy outcomes in pregnant women with a risk index above the cut-off point in first-trimester screening for fetal chromosomal abnormalities and an amniocentesis result of normal fetal karyotype in a sample of pregnant women attending our clinic at the beginning of pregnancy.

Subjects and methods

We performed a case-control study. A series of patients who underwent first-trimester combined screening as part of antenatal care between January 2009 and January 2010 were selected.

Results

Of the maternal complications registered during the pregnancy, gestational diabetes was more frequent among cases.

Conclusions

The incidence of the remaining complications analyzed (intrauterine restricted growth, preeclampsia, oligoamnios) was similar in the two groups. In most of the pregnant women, delivery occurred after 37 weeks through the vaginal route.     

Feto acardio en gestación gemelar a término

Twin reversed arterial perfusion sequence (TRAP) is a serious complication of monochorionic twin pregnancies, in which one twin perfuses the other twin (an acardiac fetus) via large arterio-arterial and veno-venous anastomoses.We report a case of monochorionic twin pregnancy at term, in which the second twin was an acardiac fetus with only an undeveloped lower limb and rudimentary colonic tissue. The first twin was born healthy, a very rare outcome in this entity as the pump twin usually shows distinct degrees of cardiac overload, leading to intrauterine death from heart failure in more than 50% of cases.     

Translucencia nucal y ductus venoso: valores de referencia en el primer trimestre de la gestación

Objective

To establish the reference ranges for nuchal translucency (NT) and ductus venosus (DV) pulsatility index for veins (PIV) in our population.

Methods

During a 4-year period, pregnancies originated from the general population undergoing 11.1-14.0 weeks ultrasound examination were studied. Reference intervals were constructed following the methodology described by the National Committee for Clinical and Laboratory Standards. According to the conclusion of the partition test, gestational age-related reference intervals were estimated using linear regression models for the NT. Deviances from linearity in the estimated models were evaluated using fractional polynomials of 1st or 2nd degree.

Results

2,612 pregnancies were studied. No significant differences were found for DV PIV between gestational age groups. There was a significant difference of the NT values between age groups (p < 0.001) and the gestational age-related estimation of reference intervals showed a no-linear increase.

Conclusion

A significant increase was found for NT with gestational age, whereas the DV PIV remained constant.     

Gestación heterotópica triple: gestación gemelar intrauterina

Heterotopic pregnancy is increasingly common in Spain mainly due to the greater use of in vitro fertilization techniques. We report a case of heterotopic pregnancy after artificial insemination in a patient who consulted for mild metrorrhagia. Ultrasound examination showed a diamniotic dichorionic twin pregnancy and a singleton intrauterine gestation in the right tube. The case was resolved by laparoscopic unilateral salpingectomy. The symptoms of these rare pregnancies are nonspecific. Moreover, they are usually underdiagnosed, because the adnexa are not usually examined when an intrauterine gestational sac is found. Due to the severity of maternal and fetal compications, early diagnosis is essential.     

Cribado combinado para la detección de trisomía 21 en el primer trimestre de la gestación. Impacto sobre la tasa de procedimientos invasivos de diagnóstico prenatal tras 5 años de implementación

Objective

To assess the effectiveness of first-trimester combined screening in the prenatal detection of Down syndrome after 5 years of use in our hospital and its impact in reducing invasive diagnostic tests.

Material and methods

The risk of fetal chromosomal anomalies was assessed in 10,669 pregnancies with first-trimester combined screening between May 2006 and December 2010. The cut-off to indicate an invasive diagnostic test was 1/270. The amniocenteses performed between 2005 and 2010 were also analyzed.

Results

The detection rate of screening for trisomy 21 was 90% and the false-positive rate was 3.56%. In pregnant women aged 35 years or more, the detection rate was 96.7%. In 2005 there were 496 amniocenteses. In 2010, 5 years after the introduction of screening, 148 amniocenteses were performed, representing a 70% reduction in invasive procedures.

Conclusions

The introduction of combined screening in our environment has proven effective for the detection of trisomy 21 and has substantially reduced the use of invasive prenatal diagnostic procedures. The use of advanced maternal age as an isolated criterion to indicate invasive techniques to study fetal karyotype should be questioned if high-quality universal screening is to be offered.     

Prevención de la hemorragia posparto en una gestante afectada de síndrome de Hermansky-Pudlack

Hermansky-Pudlak syndrome is a multisystemic disease with autosomal recessive inheritance, mainly characterized by oculo-cutaneous albinism and impaired platelet aggregation. We describe the follow–up and end of pregnancy in a 30-year-old woman with this syndrome, as well as the measures carried out during labor to avoid bleeding complications due to platelet dysfunction. The pregnancy ended at 38.2 weeks through vaginal delivery, without epidural anesthesia and good maternal and fetal outcome.     

Diagnóstico ecográfico de quistes del cordón umbilical en el primer trimestre de la gestación

Although umbilical cord cysts are a relatively frequent entity they cannot be considered a nonpathological sonographic finding. In the first trimester pregnancies the prevalence of umbilical cord cysts has been reported about 3%. Sometimes are associated to other chromosomal and/or structural abnormalities. If they are persistent and progressive in the size, could restrict the fetal sanguineous flow.     

Síndrome coronario agudo durante la gestación

Acute coronary syndrome in women aged less than 40 years old is uncommon and is even less frequent during pregnancy. However, the incidence of this syndrome can be expected to increase because associated risk factors, such as increased age at pregnancy, are becoming increasingly frequent.     

Gestación gemelar con feto muerto intraútero en el segundo trimestre

Nowadays, twin gestation is increased due to advances in assisted reproduction. Unquestionably, these pregnancies have an increased risk of foetal and maternal disorders. Single foetal death has a different incidence depending on gestational age; in the first trimester between 10-70%, in the second and third trimester it is a rare event, 0.5-7%.     

Evaluación del índice proteína-creatinina en orina aislada para la predicción de proteinuria significativa durante la gestación

Introduction

Diagnosis and follow-up of preeclampsia requires measurement of proteinuria and the gold standard for this evaluation is the 24-hour collection. However, this collection is cumbersome, time consuming and delays clinical diagnosis. The purpose of this study is assess the diagnostic performance of the spot urine protein/creatinine (P/C) ratio to predict the absence or presence of significant proteinuria (≥ 300 mg per 24 hours) among outpatient pregnant women with suspected or previous diagnosis of preeclampsia.

Material and methods

The P/C ratio was calculated in 106 single voided urine samples, obtained after the completion of the 24-hour collection, from 66 outpatient pregnant women admitted to the Maternal Fetal Care Unit at our Hospital to follow-up of hypertension gestational. Correlation between the spot urine P/C ratio with the 24-hour urine protein excretion was calculated. Receiver operator characteristic (ROC) curves analysis was used to evaluate the diagnostic performance and to determinate the best cutoff to predict the absence or presence of significant proteinuria.

Results

Significant proteinuria on 24 hour collection urine was identified in 31 urines from 22 pregnant women. There was a significant correlation between the spot urine P/C and 24-hour urine protein excretion (r_Spearman = 0,658, p = 0,01). ROC curves analysis revealed an area under the curve for spot P/C ratio of 0,838, greater than urine dipstick (0,629). No single P/C ratio cutoff was appropriate to rule-out or predict significant proteinuria; however, use of dipstick and spot urine P/C ratio, with two cutoffs, 120 mg/g to predict the absence of significant proteinuria and 240 mg/g to confirm it, clasiffied correctly 44,3% of urines and avoided the collection of 24 hours urine in 51% of the cases.

Conclusions

Spot urine P/C ratio, in conjunction with dipstick urianalysis, is a useful test in the initial screen for rule-out and predict significant proteinuria in outpatient pregnant women with hypertensive pregnancy or preeclampsia, but it should not be used as an alternative to 24-hour total protein evaluation in midrange P/C ratio, requiring a full 24-hour urine for accurate results.     

Gestación gemelar bicorial biamniótica con un feto vivo y una mola parcial del otro gemelo

Twin pregnancy with one sac containing a live fetus and a second sac containing a partial embryonic mole is an extremely rare entity. A 22-year-old nulliparous woman was admitted to our hospital at 16 weeks’ gestation due to persistent hyperemesis unresponsive to the usual medication. Ultrasound examination revealed a bichorial biamniotic twin pregnancy with one live fetus and another fetus with absent fetal heart rate and a biometry of 12-13 weeks. The placenta of the second fetus showed signs of diffuse molar changes. The diagnosis was made with chorionic villus sampling biopsy. The patient wanted to continue with the pregnancy and was followed-up as a high risk pregnancy. Labor was induced at 38 weeks’ gestation due to preeclampsia. Outcome was favorable and the patient remains asymptomatic.     

Análisis de la finalización de la gestación y morbilidad materna en las gestaciones de 41 semanas

Objective

To evaluate the mode of delivery and maternal morbidity associated with pregnancies ending at 41 weeks.

Material and methods

We designed a retrospective cohort study. The mode of delivery and maternal complications of 230 pregnancies ending at 41 weeks were compared with those in 234 pregnancies ending between 37 and 40 weeks at the Miguel Servet University Hospital in 2005.

Results

Women delivering at 41 weeks had an increased risk of membrane sweep, unfavorable Bishop score at admission, induction and longer duration of labor. These increases were also seen in the rates of operative vaginal delivery (25.6 vs 17.6%, p < 0.001) and cesarean section (21.7 vs 8.5%, p < 0.001).

Conclusions

The rates of maternal peripartum complications increase as pregnancy reaches 41 weeks. Accurate investigation of these rates is important to determine the gestational age at which the risk of continuing the pregnancy outweighs the risk of labor induction.