Microenvironment of the Lower Reproductive Tract: Focus on the Cervical Mucus Plug.

The female lower reproductive tract microbiota is a complex ecosystem comprising various microorganisms that play a pivotal role in maintaining women's reproductive well-being. During pregnancy, the vaginal microbiota undergoes dynamic changes that are important for a successful gestation. This review summarizes the implications of the cervical mucus plug microenvironment and its profound impact on reproductive health. Further, the symbiotic relationship between the vaginal microbiome and the cervical mucus plug is highlighted, with a special emphasis on how this natural barrier serves as a guardian against ascending infections. Understanding this complex host-microbes interplay could pave the way for innovative approaches to improve women's reproductive health and fertility.

Chequeo preventivo basado en la evidencia / Evidence-based health check

Un chequeo preventivo se define como el contacto entre un profesional de salud y una persona asintomática en el que se realizan varias pruebas de tamizaje para evaluar su salud con el objetivo de reducir la morbimortalidad. No obstante, la evidencia científica demuestra que realizar varias pruebas de tamizaje es poco probable que sea beneficioso para ese objetivo y cada examen debe ofrecerse de manera individualizada considerando riesgos y beneficios. Los objetivos de esta revisión son describir la utilidad de estos chequeos, revisar brevemente acciones preventivas y formular grados de recomendación, pudiendo así el lector reconocer las recomendaciones preventivas basadas en evidencia en un adulto sano. En el presente artículo se sintetizan recomendaciones utilizando la metodología GRADE en su formulación. Si bien la mayoría de las recomendaciones revisadas tienen evidencia de moderada a alta certeza, es importante considerar algunas distinciones al momento de ofrecer las acciones preventivas. Luego de este esfuerzo académico, queda en evidencia la necesidad de constituir una organización formal dedicada a la revisión, elaboración y actualización de recomendaciones preventivas en nuestro país, así como evaluar el impacto de estas acciones en cuanto a resultados de salud.

A general health check is defined as the contact between a health professional and an asymptomatic person where several screening tests are performed to assess general health with the aim of reducing morbidity and mortality. However, scientific evidence shows that performing several screening tests are unlikely to be beneficial for those outcomes and each test should be individualized considering risks and benefits.The objectives of this review are to describe the usefulness of these checks, briefly review preventive actions, and formulate degrees of recommendation, thus allowing the reader to recognize evidence-based preventive recommendations in a healthy adult.In this article, recommendations are synthesized using the GRADE methodology in its formulation. While most of the recommendations reviewed have moderate to high certainty evidence, it is important to consider some distinctions when offering preventive actions.After this academic effort, the need to establish a formal organization dedicated to the review, preparation and updating of preventive recommendations in our country is evident, as well as evaluating the impact of these actions in terms of health outcomes

Iodine Status, Thyroid Function, and Birthweight: A Complex Relationship in High-Risk Pregnancies.

(1) Background: The consequences of iodine deficiency and/or thyroid dysfunction during pregnancy have been extensively studied, emphasizing on infant neurodevelopment. However, the available information about the relationship between iodine, thyroid hormones, and fetal growth in high-risk pregnancies is limited. We aim to investigate if iodine metabolism and/or thyroid parameters can be affected by adverse antenatal/perinatal conditions. (2) Methods: A cross-sectional study examined differences in iodine status, thyroid function, and birthweight between high-risk (HR group; n = 108)) and low-risk pregnancies (LR group; n = 233) at the time of birth. Urinary iodine concentration (UIC), iodine levels in amniotic fluid, and thyroid parameters [thyroid-stimulating hormone (TSH), free thyroxine (FT4)] were measured in mother-baby pairs. (3) Results: There were significant differences between HR and LR groups, free thyroxine (FT4) concentration in cord blood was significantly higher in the LR group compared with HR pregnancies (17.06 pmol/L vs. 15.30 pmol/L, respectively; p < 0.001), meanwhile iodine concentration in amniotic fluid was significantly lower (13.11 µg/L vs. 19.65 µg/L, respectively; p < 0.001). (4) Conclusions: Our findings support the hypothesis that an adverse intrauterine environment can compromise the availability of FT4 in cord blood as well as the iodine metabolism in the fetus. These differences are more noticeable in preterm and/or small fetuses.

Influence of maternal obesity on the accuracy of ultrasonography birth weight prediction.

Objective: The aim of the study was to investigate whether the accuracy of ultrasound estimates of fetal weight (EFW) was dependent on maternal obesity.Study design: A prospective cross-sectional study of 1064 singleton pregnant women classified according to body mass index (BMI) into two categories: normal (BMI < 25 kg/m2, n = 863) and obese (BMI ≥ 35 kg/m2, n = 201) was conducted. EFW were calculated using Hadlock's formula, and the difference between EFW and the actual birthweight (absolute percent error) was analyzed in both groups. Spearman's correlation was used to assess the relationship between ultrasound performance (absolute error), maternal BMI, and actual birth weight.Results: Median absolute error of sonographic EFW was 5.90 and 6.47% for the normal and obese groups, respectively (p .38). A correlation between EFW and birth weight (BW) was found in both groups, r = 0.755 (p < .001) and r = 0.753 (p < .001), respectively. The correlation between absolute error, maternal BMI, and fetal birth weight was poor.Conclusions: Maternal obesity is unrelated to the accuracy of sonographic EFW, and regardless of maternal or fetal size, ultrasound is currently an accurate method of prediction for both obese and normal weight pregnant women.

An integrated model with classification criteria to predict vaginal delivery success after cesarean section.

Background: Cesarean delivery (CD) is the most frequently performed surgical procedure worldwide. Trial of labor after cesarean (TOLAC) is associated with an increase in perinatal complications related to uterine rupture. However, in general, vaginal birth after cesarean (VBAC) is considered safe and women have less morbidity than those who undergo an elective repeat CD.Objective: To develop an integrated model with the best performance criteria for predicting vaginal delivery success after CD.Study design: Retrospective observational study including 2367 women who underwent a TOLAC. A predictive model using classification and regression tree modeling was constructed to predict vaginal delivery using maternal demographic, medical history, and labor predictors.Results: Vaginal delivery was best predicted by spontaneous onset of labor, estimated fetal weight <3775 g, maternal body mass index <25, previous CD as an elective or for fetal distress reasons, and interdelivery interval <2290 days. The algorithm showed a sensitivity of 75%, a specificity of 53%, and the area under the curve was 0.69.Conclusions: The classification and regression tree algorithm can be used to develop a predictive model for the success of TOLAC.

Maternal obesity and the risk of group B streptococcal colonisation in pregnant women.

The aim of the study was to test if maternal obesity and being overweight are independent risk factors for rectovaginal Group B Streptococcus (GBS) colonisation in pregnancy and for early onset GBS disease in the neonate. A case-control study of 9877 deliveries was conducted. The obese gravidas were significantly more likely to be colonised by GBS when compared with non-obese gravidas (22.7% versus 17.5%, P < .001). Obese gravidas were still 33% more likely than non-obese women to test positive for GBS after adjusting for the perinatal factors (adjusted OR 1.33 [95% CI 1.12-1.56]). The risk of early onset GBS disease was not calculated due to its very low incidence. The conclusion is that maternal obesity is a significant risk factor for GBS colonisation at term. Impact statement What is already known on this subject? Group B Streptococcus (GBS) is as an important cause of perinatal mortality and morbidity if prophylaxis is not performed. Intrapartum antibiotics are given if the carrier status is positive or unknown, provided that the risk factors are present. What do the results of this study add? Maternal obesity is a significant and independent risk factor for GBS colonisation at term. What are the implications of these findings for clinical practice and/or further research? Maternal obesity may be considered as a risk factor that should be taken into account in strategies for reducing GBS disease in neonates.

Cardiotocography alone vs. cardiotocography with ST segment analysis for intrapartum fetal monitoring in women with late-term pregnancy. A randomized controlled trial.

OBJECTIVES: Randomized studies have obtained conflicting results regarding the usefulness of fetal electrocardiographic (ECG) ST-segment analysis, possibly because these studies included non-homogeneous populations. We designed a study to determine whether this monitoring technique is potentially useful for populations at risk for fetal heart rate alterations during labor, i.e. groups of women who share late-term pregnancy as a risk factor. STUDY DESIGN: This randomized clinical trial recruited women whose pregnancy had lasted more than 290 days. The participants were randomly assigned to continuous fetal cardiotocographic monitoring alone (CTG group) or with fetal ECG ST-segment analysis (ECG-F group). In the CTG group fetal heart rate was interpreted according to guidelines from the National Institute of Child Health and Human Development, whereas in the ECG-F group the tracings were interpreted according the original International Federation of Gynecology and Obstetrics (FIGO) guidelines. The primary outcome measure was neonatal outcome, evaluated as arterial blood pH in neonates after abdominal or vaginal operative delivery indicated because of nonreassuring fetal status. RESULTS: A total of 237 women were randomized, of whom 200 were included in the final analysis (100 in each group). The rate of cesarean delivery was the same in both groups (26%), and the rate of operative delivery due to nonreassuring fetal status did not differ significantly (38% in the CTG group vs. 39% in the ECG-F group). Regarding neonatal outcomes, there was no significant difference between groups in neonatal pH (7.27 [7.23-7.29] and 7.25 [7.21-7.27]). CONCLUSIONS: In a population comprising only late-term pregnancies, fetal ECG monitoring had no benefits for the mother or fetus. Additional studies are needed of protocols for using ST waveform analysis in selected population groups.

Risk of recurrence of small-for-gestational-age foetus after first pregnancy.

The aim of this study was to assess the incidence of and to analyse factors related to the recurrence of small-for-gestational-age (SGA) neonates in the second pregnancy. A prospective observational study was conducted at a tertiary university hospital in Granada, Spain. A total of 7896 women who delivered their first and second singleton pregnancies at the hospital from 2003-2013 were included and evaluated all birth weights. Women whose first pregnancy was complicated by a SGA birth had a fivefold increased risk of recurrence (23.6% vs. 5.7%, p < .001). Multivariate analyses revealed that only SGA at first birth retained a statistically significant relationship, revealing that the other variables (maternal age, gestational age, interdelivery interval, maternal pre-pregnancy body mass index, occupation of the mother, smoking, hypertension, and diabetes mellitus) were confounders. Prevention of SGA in subsequent pregnancies by modification of established risk factors could be of limited utility based on the present results, supporting a genetic contribution to SGA recurrence. Impact statement The results support a genetic contribution on recurrence of SGA.

Accuracy of fetal sex determination on ultrasound examination in the first trimester of pregnancy.

PURPOSE: The aim of this study was to evaluate the feasibility and success rate of sex determination on transabdominal sonographic examination at 11-13 weeks' gestation and to identify factors influencing accuracy. METHODS: In this prospective observational evaluation of 672 fetuses between 11 weeks' and 13 weeks + 6 days' gestational age (GA), we determined fetal sex according to the angle of the genital tubercle viewed on the midsagittal plane. We also analyzed maternal, fetal, and operator factors possibly influencing the accuracy of the determination. RESULTS: Fetal sex determination was feasible in 608 of the 672 fetuses (90.5%), and the prediction was correct in 532 of those 608 cases (87.5%). Fetal sex was more accurately predicted as the fetal crown-rump length (CRL), and GA increased and was less accurately predicted as the maternal body mass index increased. A CRL greater than 55.7 mm, a GA more than 12 weeks + 2 days, and a body mass index below 23.8 were identified as the best cutoff values for sex prediction. None of the other analyzed factors influenced the feasibility or accuracy of sex determination. CONCLUSIONS: The sex of a fetus can be accurately determined on sonographic examination in the first trimester of pregnancy; the accuracy of this prediction is influenced by the fetal CRL and GA and by the maternal body mass index. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:272-277, 2016.

Noninvasive fetal RhD status determination in early pregnancy.

INTRODUCTION: The aim of this study was to examine if noninvasive fetal RhD genotyping from maternal blood cell-free fetal DNA performed in the first trimester of pregnancy is accurate enough to propose its routine application to replace usual immunoprophylaxis. MATERIAL AND METHODS: We carried out a prospective study analyzing fetal RhD genotype in 149 nonimmunized RhD-negative women with single pregnancies between 8 and 13 weeks of gestation. Fetal RhD genotype was detected by quantitative PCR targeting exons 5 and 7. The results were compared with postnatal cord blood phenotype, and discrepancy rates were calculated. RESULTS: The concordance of fetal RhD genotypes in maternal plasma and newborn D phenotypes at delivery was 98.2%, including 1 false-positive and 1 false-negative result. The specificity and sensitivity of the assay were 97.5% (95% CI 87.1-99.9) and 98.6% (95% CI 92.7-99.9), respectively, and 6.5% of the results were inconclusive. The application of this test in early pregnancy would avoid unnecessary antenatal prophylaxis in about 27% (40/143) of nonsensitized RhD-negative women. DISCUSSION: Determination of the fetal RhD status from cell-free fetal DNA in maternal plasma in the first trimester of pregnancy is feasible and highly accurate, thus allowing consideration of replacing general routine immunoprophylaxis in the cases of mothers with Rh-negative fetuses.

Risk of episiotomy and perineal lacerations recurring after first delivery.

BACKGROUND: To assess whether the presence of an episiotomy or spontaneous perineal trauma at the first delivery increases the risk of perineal trauma at the following one. METHODS: We studied 2,695 women who gave birth twice at Virgen de las Nieves University Hospital of Granada, Spain. All second deliveries were from 2004 to 2011 and prenatal database records were used to obtain information about the first deliveries. All births, first and second, were single, vaginal, unassisted, and in a cephalic presentation. Two groups were made as follows: Intact perineum (no perineal trauma or first-degree spontaneous tear at the first delivery) and perineal trauma (episiotomy or second-degree or higher spontaneous tear at the first delivery). Both groups were compared according to the degree of perineal trauma at the second delivery. RESULTS: Women included in the perineal trauma group were significantly older and a higher proportion was attended by a midwife with an obstetrician present in the delivery room. No differences were observed according to gestational age, epidural analgesia or fetal birth weight. Adjusting for these possible compounding factors and the year of birth, the risk of undergoing a second-degree or higher spontaneous tear at their next delivery was fivefold (adjusted OR 5.15, 95% CI 3.11-8.54), and the risk of undergoing an episiotomy in the second delivery was threefold (adjusted OR 3.20, 95% CI 2.19-4.69) for the perineal trauma group. CONCLUSION: The risk of undergoing a spontaneous perineal tear or an episiotomy in the second delivery is increased by the practice of episiotomy in the first one.

Perinatal outcomes in preterm growth-restricted twins: effects of gestational age and fetal condition.

OBJECTIVE: To evaluate the perinatal outcome of intrauterine growth-restricted preterm twins and contribution of prematurity to morbidity and mortality. STUDY DESIGN: A case-control study of 211 preterm twins: 108 growth-restricted twins matched with 103 normal growth twins of the same gestational age. Mortality and morbidity rates were compared between groups. RESULT: Fetal and overall perinatal mortality rates of growth-restricted fetuses were higher than normal growth ones. Respiratory distress syndrome incidence was lower and neurologic sequelae incidence higher in growth-restricted twins. No differences were observed between groups with respect to neonatal mortality, low Apgar score, neonatal intensive care unit admission, periventricular hemorrhage, sepsis, jaundice, and hematologic or metabolic disorders. CONCLUSION: Adverse perinatal outcomes of preterm twins complicated with intrauterine growth restriction are represented by a higher antepartum mortality rate, but once born alive, neonatal outcomes seem to be associated only with gestational age at birth, excluding a protective effect on lung maturation and a higher risk of long-term neurologic sequelae.