First-trimester cervical inflammatory milieu and subsequent early preterm birth

The dosing regimen for 17-hydroxyprogesterone caproate was suboptimal: lessons for future pharmacotherapy for pregnant women

BACKGROUND

Makena (17-hydroxyprogesterone caproate) was approved by the United States Food and Drug Administration for the prevention of recurrent spontaneous preterm birth in 2011 under the accelerated approval pathway, but fundamental pharmacokinetic or pharmacodynamic (Phase 1 and Phase 2) studies were not performed. At the time, there were no dose-response or concentration-response data. The therapeutic concentration was not known. The lack of such data brings into question the dosing regimen for 17-hydroxyprogesterone caproate and if it was optimized.

OBJECTIVE

The purpose of this study was to evaluate the dosing regimen for 17-hydroxyprogesterone by analyzing 3 data sets in which the 17-hydroxyprogesterone caproate pharmacology was evaluated, namely the Maternal-Fetal Medicine Omega 3 study, the Obstetric-Fetal Pharmacology Research Units study, and the Obstetrical-Fetal Pharmacology Research Centers study. If an inappropriate dosing regimen could be identified, such information could inform future studies of pharmacotherapy in pregnancy.

STUDY DESIGN

Data from the Omega 3 study were used to determine if plasma concentration was related to spontaneous preterm birth risk and if a threshold concentration could be identified. Data from the Obstetric-Fetal Pharmacology Research Units study were used to determine the half-life of 17-hydroxyprogesterone caproate and to develop a model to simulate drug concentrations with various dosing regimens. Data from the Obstetrical-Fetal Pharmacology Research Centers study were used to determine the relationship between dose and safety outcomes.

RESULTS

Analysis of the Omega 3 data set indicated that the risk for spontaneous preterm birth decreased as the log concentration of 17-hydroxyprogesterone caproate increased (odds ratio, 0.04; 95% confidence interval, 0.00-0.90). A steady state concentration of >9 ng/mL (equivalent to >8 ng/mL at 25-28 weeks) was associated with the lowest risk for spontaneous preterm birth (hazard ratio, 0.52; 95% confidence interval, 0.27-0.98; P=.04); this concentration was not achieved in 25% of subjects who received the 250 mg weekly dose. In the Obstetrical-Fetal Pharmacology Research Units study, the adjusted half-life (median and interquartile range) of 17-hydroxyprogesterone caproate was 14.0 (11.5-17.2) days. Simulations indicated that with the 250 mg weekly dose, >5 weekly injections were required to reach the 9 ng/mL target; however, those with the shortest half-life (corresponding to higher clearance), never reached the targeted 9 ng/mL concentration. In 75% of subjects, a loading dose of 500 mg weekly for 2 weeks followed by 250 mg weekly achieved and maintained the 9 ng/mL concentration within 2 weeks but in those 25% with the shortest half-life, concentrations exceeded the 9 ng/mL target for only 3 weeks. In the Obstetrical-Fetal Pharmacology Research Centers study, all 65 subjects who received a weekly dose of 500 mg exceeded the 9 ng/mL steady state.

CONCLUSION

The dosing regimen for 17-hydroxyprogesterone caproate was inadequate. There is a significant inverse relationship between drug concentration and spontaneous preterm birth. The risk was lowest when the concentration exceeded 9 ng/mL, but 25% of women who received the 250 mg weekly dose never reached or maintained this concentration. The drug's long half-life necessitates a loading dose to achieve therapeutic concentrations rapidly. The omission of basic pharmacologic studies to determine the proper dosing may have compromised the effectiveness of 17-hydroxyprogesterone caproate. Future pharmacotherapy trials in pregnancy must first complete fundamental pharmacology studies.

Elevated midtrimester maternal plasma cytokines and preterm birth in patients with cerclage

BACKGROUND

Cerclage is used for the prevention of spontaneous preterm birth; however, many patients at high risk of spontaneous preterm birth who have a cerclage in place eventually deliver before term. Although inflammation, measured by biomarkers (eg, cytokines), is a known risk factor for preterm delivery, evaluation of inflammation to determine pregnancy outcomes among patients with cerclage is poorly understood.

OBJECTIVE

We sought to examine levels of maternal plasma inflammatory cytokines in the midtrimester among asymptomatic patients with a cervical cerclage (placed for any indication, including history, ultrasound, and examination indications) to evaluate the association between cytokine levels and preterm birth.

STUDY DESIGN

This was a prospective cohort study of singleton, nonanomalous pregnancies who had a cerclage placed at <24 weeks of gestation from 2015 to 2018 at a single tertiary institution. Maternal plasma was collected perioperatively whenever possible. A custom magnetic bead Luminex cytokine assay was used to measure plasma inflammatory cytokine levels from these stored samples. The primary outcome was preterm birth at <37 weeks of gestation. A statistical cut point was calculated for each cytokine level to assess its optimal sensitivity and specificity for spontaneous preterm birth prediction. Patients were classified as having a "high" or "low" result for each cytokine based on this cut point. Receiver operating characteristic curve analysis was performed to estimate sensitivity, specificity, and positive and negative predictive values for spontaneous preterm birth prediction. Cox proportional-hazards regression modeled the association between the number of "high" inflammatory cytokines and gestational age at delivery, adjusting for confounders. Additional analyses were performed on the subgroup of patients with history-indicated cerclage and those with an ultrasound- or examination-indicated cerclage.

RESULTS

A total of 43 patients participated in this study: 20 (46.5%) had spontaneous preterm birth (median, 30.9 weeks of gestation; interquartile range, 28.4-35.0). Plasma samples were collected at a median of 0 (interquartile range, -2 to 17) days concerning cerclage placement and a median of 18 (interquartile range, 13-21) weeks of gestation. Based on the statistical cut point for each cytokine level, 7% of patients had zero, 20.9% had 1, 18.6% had 2, 20.9% had 3, and 32.6% had ≥4 "high" cytokine results. Each additional "high" cytokine level was associated with earlier delivery (hazard ratio, 1.51; 95% confidence interval, 1.25-1.81) even after controlling for ultrasound- or examination-indication for cerclage (hazard ratio, 1.73; 95% confidence interval, 0.95-3.15). The presence of ≥4 "high" cytokine levels was 70% sensitive and 74% specific for predicting spontaneous preterm birth (area under the curve, 0.846; 95% confidence interval, 0.728-0.964; positive predictive value, 70%; negative predictive value, 73.9%).

CONCLUSION

Among patients with a cervical cerclage, elevated midtrimester maternal plasma cytokine profiles were associated with subsequent preterm birth and can estimate the probability of preterm birth. Confirmation and refinement of this noninvasive panel may provide insight into improved selection of individuals who may benefit from cerclage placement and investigation of therapeutic strategies to mitigate midpregnancy inflammation.

Concentration of vaginal and systemic cytokines obtained early in pregnancy and their impact on preterm birth

OBJECTIVE

A number of factors can lead to a maternal pro-inflammatory response resulting in a spontaneous preterm birth. However, it remains unknown if an upregulation in the maternal immune system early in pregnancy leads to an increase in pro-inflammatory cytokines and ultimately preterm birth. Therefore, we hypothesize an increase in vaginal and systemic pro-inflammatory cytokines early pregnancy is associated with an increased risk of preterm birth.

STUDY DESIGN

Patients initiating prenatal care prior to 14 weeks gestation were recruited for eligibility. A vaginal swab and serum sample was obtained at the first prenatal visit and these were then stored at -80 C. Patients were then followed for their gestational age at delivery. Five patients delivering preterm (cases) were matched with ten patients delivering at term (controls) based on age, BMI, smoking status and ethnicity. The serum and vaginal swabs from the cases and controls were then analyzed for the following cytokines using a multiplex cytokine assay: GM-CSF, IL-1b, IL-6, TNFα, and Rantes.

RESULTS

A total of 116 patients were screened for eligibility and 96 of these patients had samples obtained prior to 14 weeks gestation. Of these 96, 5 had a spontaneous preterm birth and these were matched to 10 controls. There was no difference detected in the cytokine concentrations of GM-CSF, IL-1b, IL-6, TNFα, and Rantes in the serum or cervicovaginal fluid between cases and controls.

CONCLUSION

This study demonstrates there is no difference in cytokine concentrations of several pro-inflammatory cytokines in the vagina or in the serum prior to 14 weeks gestation in patients delivering preterm. Therefore, the concentration of the cytokines analyzed in this study from the vagina and serum have little predictive value on the risk of preterm birth. Further research is needed to deepen our understanding of the mechanisms leading to preterm birth.

Timing of Cervico-Vaginal Cytokine Collection during Pregnancy and Preterm Birth: A Comparative Analysis in the PRINCESA Cohort

Preterm birth (PTB), defined as birth before 37 completed weeks of gestation, is a major cause of infant morbidity and mortality. Inflammation is an important component in the physiopathologic pathway leading to PTB but results from cross-sectional studies on associations between inflammation, as measured by cytokines, and PTB are inconsistent. Timing of cytokine measurement during pregnancy varies between studies and may contribute to inconsistent findings. We investigated the effects of timing on associations between 16 cervico-vaginal cytokines (Eotaxin, IL-10, IL-12p40, IL-17, IL-1RA, sIL-2rα, IL-1a, IL-1β, IL-2, IL-6, IP-10, MCP-1, MIP-1α, MIP-1β, TNFα, and VEGF) and PTB among 90 women throughout pregnancy. We used logistic regression to compare associations between concentrations of cervico-vaginal cytokines from periods in pregnancy and PTB. Trimester 1 cytokines had the strongest positive associations with PTB; for example, OR = 1.76 (95% confidence interval: 1.28, 2.42) for IL-6. Second and third trimester associations were weaker but largely positive. IL-1α was the only cytokine with a negative association (trimesters 2, 3 and overall pregnancy). Strong first trimester associations between cytokines and PTB suggest that measuring cytokines early in pregnancy may hold promise for early identification of PTB risk. Variations in cytokine measurement during pregnancy may contribute to inconsistencies among studies.

Identification and evaluation of the microbiome in the female and male reproductive tracts

BACKGROUND

The existence of an extensive microbiome in and on the human body has increasingly dominated the scientific literature during the last decade. A shift from culture-dependent to culture-independent identification of microbes has occurred since the emergence of next-generation sequencing (NGS) techniques, whole genome shotgun and metagenomic sequencing. These sequencing analyses have revealed the presence of a rich diversity of microbes in most exposed surfaces of the human body, such as throughout the reproductive tract. The results of microbiota analyses are influenced by the technical specifications of the applied methods of analyses. Therefore, it is difficult to correctly compare and interpret the results of different studies of the same anatomical niche.

OBJECTIVES AND RATIONALE

The aim of this narrative review is to provide an overview of the currently used techniques and the reported microbiota compositions in the different anatomical parts of the female and male reproductive tracts since the introduction of NGS in 2005. This is crucial to understand and determine the interactions and roles of the different microbes necessary for successful reproduction.

SEARCH METHODS

A search in Embase, Medline Ovid, Web of science, Cochrane and Google scholar was conducted. The search was limited to English language and studies published between January 2005 and April 2018. Included articles needed to be original microbiome research related to the reproductive tracts.

OUTCOMES

The review provides an extensive up-to-date overview of current microbiome research in the field of human reproductive medicine. The possibility of drawing general conclusions is limited due to diversity in the execution of analytical steps in microbiome research, such as local protocols, sampling methods, primers used, sequencing techniques and bioinformatic pipelines, making it difficult to compare and interpret results of the available studies. Although some microbiota are associated with reproductive success and a good pregnancy outcome, it is still unknown whether a causal link exists. More research is needed to further explore the possible clinical implications and therapeutic interventions.

WIDER IMPLICATIONS

For the field of reproductive medicine, determination of what is a favourable reproductive tract microbiome will provide insight into the mechanisms of both unsuccessful and successful human reproduction. To increase pregnancy chances with live birth and to reduce reproduction-related health costs, future research could focus on postponing treatment or conception in case of the presence of unfavourable microbiota and on the development of therapeutic interventions, such as microbial therapeutics and lifestyle adaptations.

Predictive value of cervical cytokine, antimicrobial and microflora levels for pre-term birth in high-risk women

Spontaneous preterm birth (sPTB, delivery <37 weeks gestation), accounts for approximately 10% of births worldwide; the aetiology is multifactorial with intra-amniotic infection being one contributing factor. This study aimed to determine whether asymptomatic women with a history of sPTB or cervical surgery have altered levels of inflammatory/antimicrobial mediators and/or microflora within cervical fluid at 22-24 weeks gestation. External cervical fluid was collected from women with history of previous sPTB and/or cervical surgery at 22-24 weeks gestation (n = 135). Cytokine and antimicrobial peptides were measured on a multiplex platform or by ELISA. qPCR was performed for detection of 7 potentially pathogenic bacterial species. IL-8 and IL-1β levels were lower in women who delivered preterm compared to those who delivered at term (IL-8 P = 0.02; IL-1β P = 0.04). There were no differences in elafin or human beta defensin-1 protein levels between the two groups. Multiple bacterial species were detected in a higher proportion of women who delivered preterm than in those who delivered at term (P = 0.005). Cervical fluid IL-8 and IL-1β and microflora have the potential to be used as biomarkers to predict sPTB in high risk women.

Maternal pro-inflammatory state during pregnancy and newborn leukocyte telomere length: A prospective investigation

INTRODUCTION

Telomere biology plays a fundamental role in maintaining the integrity of the genome and cell, and shortened telomeres have been linked to several age-related diseases. The initial (newborn) telomere length (TL) represents a critically important feature of the telomere biology system. Exposure to a variety of adverse prenatal conditions such as maternal stress, suboptimal diet, obesity, and obstetric complications, is associated with shorter offspring TL at birth and in adult life. Many, if not all, of these exposures are believed to have an inflammatory component. In this context, stress-related immunological processes during pregnancy may constitute a potential additional biological pathway because they can affect telomere length and telomerase activity via transcriptions factors such as cyclic adenosine monophosphate-dependent transcription factor (ATF7) and nuclear factor-kappa B (NF-κB). Thus, in the present study we examined the hypothesis that maternal pro-inflammatory state across pregnancy, operationalized as the balance between tumor necrosis factor (TNF)-α, a major pro-inflammatory cytokine, and interleukin-10 (IL-10), the major anti-inflammatory cytokine, is associated with newborn leukocyte telomere length (LTL) at birth.

METHODS AND MATERIALS

Participants were healthy women (N = 112) recruited in early pregnancy. Concentrations of TNF- α and IL-10 were quantified in early, mid and late pregnancy from maternal blood samples. Telomere length was assessed in newborn blood samples soon after birth.

RESULTS

After adjusting for maternal age, maternal pre-pregnancy BMI, birth weight percentile, and infant sex, a higher mean TNF-α/IL-10 ratio across pregnancy was significantly associated with shorter newborn TL (β = -.205, p = .030). Newborn TL was, on average, 10% shorter in offspring of women in the upper compared to lower quartile of the TNF-α/IL-10 ratio during pregnancy.

DISCUSSION

These findings provide new evidence in humans for a potential "programming" mechanism linking maternal systemic pro-inflammatory processes during pregnancy with the initial (newborn) setting of her offspring's telomere system.

Associations of first trimester co-use of tobacco and Cannabis with prenatal immune response and psychosocial well-being

PURPOSE

This study aims to describe the association of first trimester co-use of tobacco and cannabis with maternal immune response and psychosocial well-being, relative to tobacco use only.

METHODS

A preliminary midpoint analysis included 138 pregnant women with biologically verified tobacco use, 38 of whom (28%) also tested positive for recent cannabis use. Maternal perceived stress (Perceived Stress Scale), depressive symptoms (Edinburgh Postnatal Depression Scale), and serum immune markers (IL-1β, IL-2, IL-6, IL-8, IL-10, TNFα, CRP, MMP8), were collected, although cytokine data were only available for 122 women.

RESULTS

Participant average age was 29.1 years, approximately half had a high school education or less, and half were unemployed. Compared to tobacco only users, co-users were more likely to be non-White, younger and more economically disadvantaged. In the adjusted linear regression models, TNF-α levels were significantly lower among co-users relative to tobacco only users, after adjusting for age, race/ethnicity, body mass index and tobacco use group (tobacco cigarettes, electronic nicotine delivery devices [ENDS] or both). TNF-α was the only immune marker found to be significant in this analysis. Measured stress levels (M = 5.9, SD = 3.3; potential range 0-16) and depression scores (M = 7.8, SD = 5.8; potential range 0-30) were low across all participants and did not differ as a function of co-use.

CONCLUSION

Preliminary results suggest women co-using during the first trimester exhibit decreased pro-inflammatory immune responsivity on one out of eight markers. Further research is needed to determine the impact of this immune modulation on fetal health outcomes and the unique contribution of cannabis.

Obstructive sleep apnea and the risk of preterm delivery

OBJECTIVE

The aim of this study was to evaluate the risk of obstructive sleep apnea (OSA) to preterm delivery (PTD), using the Berlin Questionnaire (BQ).

METHODS

This was a large, prospective cohort study among pregnant Thai women. The BQ was employed for symptom-based OSA screening during the second trimester, and PTD was recorded in 1345 pregnant women. Multivariate models were applied in controlling for potential confounders.

RESULTS

The overall prevalence of the high risk of OSA was 10.1 %, and it was significantly associated with pre-pregnancy body mass index and score on the Perceived Stress Scale. An adjusted odds ratio for PTD in women with a high risk of OSA was 2.00 (95 % confidence intervals (CIs) = 1.20, 3.34). Stratified analyses, after adjusting for confounding factors, indicated that a high risk of OSA was associated with an increased risk of spontaneous preterm delivery (odds ratio (OR) = 2.45, 95 % CI = 1.20, 5.02), but not with preterm premature rupture of membranes (OR = 1.61, 95 % CI = 0.61, 4.26), and medically indicated preterm delivery (OR = 1.83, 95 % CI = 0.72, 4.64).

CONCLUSION

Pregnant women with a high risk of OSA are at an increased risk of having PTD, compared with pregnant women with a low risk of OSA.

Polyunsaturated Fatty Acid (PUFA) Status in Pregnant Women: Associations with Sleep Quality, Inflammation, and Length of Gestation

Mechanistic pathways linking maternal polyunsaturated fatty acid (PUFA) status with gestational length are poorly delineated. This study examined whether inflammation and sleep quality serve as mediators, focusing on the antiinflammatory ω-3 docosahexaenoic acid (DHA; 22:6n3) and proinflammatory ω-6 arachidonic acid (AA; 20:4n6). Pregnant women (n = 135) provided a blood sample and completed the Pittsburgh Sleep Quality Index (PSQI) at 20–27 weeks gestation. Red blood cell (RBC) fatty acid levels were determined by gas chromatography and serum inflammatory markers [interleukin (IL)-6, IL-8, tumor necrosis factor-α, IL-1β, and C-reactive protein] by electrochemiluminescence using high sensitivity kits. Both higher serum IL-8 (95% CI = 0.10,3.84) and poor sleep (95% CI = 0.03,0.28) served as significant mediators linking lower DHA:AA ratios with shorter gestation. Further, a serial mediation model moving from the DHA:AA ratio → sleep → IL-8 → length of gestation was statistically significant (95% CI = 0.02, 0.79). These relationships remained after adjusting for depressive symptoms, age, BMI, income, race, and smoking. No interactions with race were observed in relation to length of gestation as a continuous variable. However, a significant interaction between race and the DHA:AA ratio in predicting preterm birth was observed (p = 0.049); among African Americans only, odds of preterm birth decreased as DHA:AA increased (p = 0.048). These data support a role for both inflammatory pathways and sleep quality in linking less optimal RBC PUFA status with shorter gestation in African American and European American women and suggest that African-Americans have greater risk for preterm birth in the context of a low DHA:AA ratio.

Vaginal Mucosal Homeostatic Response May Determine Pregnancy Outcome in Women With Bacterial Vaginosis: A Pilot Study

Bacterial vaginosis (BV) is considered as a trigger for an inflammatory response that could promote adverse pregnancy outcome (APO). We hypothesized that BV-related inflammation could be counterbalanced by anti-inflammatory and mucosal homeostatic responses that could participate in pregnancy outcomes.A total of 402 vaginal self-samples from pregnant women in their first trimester were screened by Nugent score. In this population, we enrolled 23 pregnant women with BV but without APO, 5 pregnant women with BV and developing APO, 21 pregnant women with intermediate flora, and 28 random control samples from pregnant women without BV or APO.BV without APO in pregnant women was associated with 28-fold interleukin-8, 5-fold interleukin-10, and 40-fold interleukin-22 increases in expression compared to controls. BV associated with APO in pregnant women shared 4-fold increase in tumor necrosis factor, 100-fold decrease in interleukin-10, and no variation in interleukin-22 expressions compared to controls. Next-generation sequencing of vaginal microbiota revealed a shift from obligate anaerobic bacteria dominance in BV without APO pregnant women to Lactobacillus dominance microbiota in BV with APO.Our results show that the anti-inflammatory and mucosal homeostatic responses to BV may determine outcome of pregnancy in the setting of BV possibly through effects on the vaginal microbiota.

Cytokine Patterns in Healthy Adolescent Girls: Heterogeneity Captured by Variable and Person-Centered Statistical Strategies

BACKGROUND

Little is known about variation in individual cytokines/cytokine profiles for a large healthy, pediatric population. When cytokines in a healthy group are not abnormally high as in a disease state, it is challenging to determine appropriate statistical strategies. The aims of the study were (1) to describe variation among cytokine concentrations and profiles in healthy adolescent girls, (2) to illustrate utility of data reduction approaches novel to cytokine research, (variable-centered [principal factor analysis, PFA], person-centered [latent profile analysis, LPA]), and (3) to demonstrate utility of such methods in linking cytokine profiles to health outcomes (e.g., depressive, anxiety symptoms).

METHOD

Serum was analyzed for 13 cytokines representing adaptive and innate immune responses in 262 girls (age = 11, 13, 15, and 17 years).

RESULTS

There was great variation in cytokine concentrations. PFA revealed a four-factor solution explaining 73.13% of the shared variance among 13 cytokines (e.g., factor 1 included interleukin [IL]-4, IL-13, IL-5, interferon gamma; 26.65% of the shared variance). The LPA supported classifying girls into subgroups characterized by "high overall" (7.3% of sample), "high adaptive" (26.7%), "high innate" (21%), or "low overall" (45%) cytokine levels. Factors and profiles were useful in describing individual differences in depressive/anxiety symptoms (e.g., factor 1 positively associated with depressive symptoms but negatively with trait anxiety; increased depressive symptoms or trait anxiety was associated with greater likelihood of being in the "high adaptive" group).

CONCLUSIONS

Healthy girls showed differences in cytokine levels and patterns of variation and important associations with psychological variables. PFA and LPA offer novel approaches useful for examining cytokine panels in healthy populations.

Disturbed sleep and inflammatory cytokines in depressed and nondepressed pregnant women: an exploratory analysis of pregnancy outcomes

OBJECTIVE

Disturbed sleep and depression are potential risk factors for pregnancy complications. Both conditions are known to dysregulate biological pathways responsible for maintaining homeostatic balance and pregnancy health. Depression during pregnancy is associated with poor sleep. Thus, we explored whether disturbed sleep was associated with inflammatory cytokines and risk for adverse pregnancy outcomes, as well as whether depression augmented the sleep-cytokine relationship, thereby additively contributing to risk for adverse outcomes.

METHODS

Interview-assessed sleep and plasma cytokine concentrations were evaluated in a cohort of depressed and nondepressed pregnant women (n = 168) at 20 and 30 weeks' gestation. Outcomes evaluated included preterm birth, birth weight, and peripartum events.

RESULTS

Among depressed women, short sleep duration (<7 hours) was associated with higher interleukin (IL)-8 across time (β = 0.506, p = .001), poor sleep efficiency (<85%) was associated with higher IL-6 (β = 0.205, p = .006), and daytime naps were associated with higher tumor necrosis factor α (β = 0.105, p = .024). Aspects of poor sleep were associated with having a lower weight baby (p values <.053). Among depressed women, interferon-γ increased risk for preterm birth (odds ratio = 1.175, p = .032). Trends for IL-6 and higher birth weight (β = 105.2, p = .085), interferon-γ and lower birth weight (β = -19.92, p < .069), and increased IL-8 and babies weighing less than 4000 grams (odds ratio = 0.72, p < .083) were observed.

CONCLUSIONS

Although speculative, disturbed sleep may disrupt normal immune processes and contribute to adverse pregnancy outcomes. Exploratory analyses indicate that depression modifies these relationships.

Associations between vaginal bacteria and levels of vaginal defensins in pregnant women

OBJECTIVE

We evaluated vaginal defensin concentrations and levels of bacterial vaginosis-associated bacterial species in pregnant women.

STUDY DESIGN

Self-collected vaginal swabs from 2 visits during pregnancy were tested with quantitative polymerase chain reaction for 9 bacterial species. Beta defensins 2-3 and alpha defensins 1-3 were measured by enzyme-linked immunosorbent assay.

RESULTS

Our 126 participants were primarily African American (60%), had a mean gestational age at enrollment of 10 ± 3 weeks and at follow-up visit of 25 ± 6 weeks. At enrollment, the prevalence of bacterial vaginosis was 74% (94/126 women), which decreased to 60% (75/126 specimens) at follow-up visit. At enrollment, beta defensin 3 concentrations were significantly lower in women with bacterial vaginosis (2.64 ± 0.91 vs 3.25 ± 0.99 log(10) pg/mL; P = .003). Higher concentrations of Atopobium vaginae, bacterial vaginosis-associated bacteria1 and 2 were associated with significantly lower concentrations of beta defensin 3 (P < .01).

CONCLUSION

Bacterial vaginosis was associated with lower vaginal concentrations of beta defensin 3, but not beta defensin 2 or alpha defensins 1-3, in pregnant women.

Limited relationship between cervico-vaginal fluid cytokine profiles and cervical shortening in women at high risk of spontaneous preterm birth

Objective

To determine the relationship between high vaginal pro-inflammatory cytokines and cervical shortening in women at high risk of spontaneous preterm labor and to assess the influence of cervical cerclage and vaginal progesterone on this relationship.

Methods

This prospective longitudinal observational study assessed 112 women with at least one previous preterm delivery between 16 and 34 weeks’ gestation. Transvaginal cervical length was measured and cervico-vaginal fluid sampled every two weeks until 28 weeks. If the cervix shortened (<25 mm) before 24 weeks’ gestation, women (cases) were randomly assigned to cerclage or progesterone and sampled weekly. Cytokine concentrations were measured in a subset of cervico-vaginal fluid samples (n = 477 from 78 women) by 11-plex fluid-phase immunoassay.

Results

All 11 inflammatory cytokines investigated were detected in cervico-vaginal fluid from women at high risk of preterm birth, irrespective of later cervical shortening. At less than 24 weeks’ gestation and prior to intervention, women destined to develop a short cervix (n = 36) exhibited higher cervico-vaginal concentrations than controls (n = 42) of granulocyte-macrophage colony-stimulating factor [(GM-CSF) 16.2 fold increase, confidence interval (CI) 1.8–147; p = 0.01] and monocyte chemotactic protein-1 [(MCP-1) 4.8, CI 1.0–23.0; p = 0.05]. Other cytokines were similar between cases and controls. Progesterone treatment did not suppress cytokine concentrations. Interleukin (IL)-6, IL-8, granulocyte colony-stimulating factor (G-CSF), interferon (IFN)-γ and tumour necrosis factor (TNF)-α concentrations were higher following randomization to cerclage versus progesterone (p<0.05). Cerclage, but not progesterone treatment, was followed by a significant increase in cervical length [mean 11.4 mm, CI 5.0–17.7; p<0.001].

Conclusions

Although GM-CSF and MCP-1 cervico-vaginal fluid concentrations were raised, the majority of cervico-vaginal cytokines did not increase in association with cervical shortening. Progesterone treatment showed no significant anti-inflammation action on cytokine concentrations. Cerclage insertion was associated with an increase in the majority of inflammatory markers and cervical length.

Poor sleep quality is associated with preterm birth

STUDY OBJECTIVES

Preterm birth (PTB) is a major public health priority and the most common adverse pregnancy outcome. Several risk factors have been identified, but a gap in the understanding of the underlying etiology of PTB persists. Poor sleep quality is a correlate of adverse health outcomes. Therefore, we evaluated whether sleep quality during pregnancy was a clinically relevant risk factor for PTB.

DESIGN

Observational.

MEASUREMENTS AND RESULTS

Participants included 166 pregnant women (mean age = 28.6 ± 5.5 years). Self-report questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), were administered at 14-16, 24-26, and 30-32 weeks gestation. Logistic regression models were used to evaluate whether sleep quality was associated with preterm delivery. Poor sleep quality was a predictor of preterm birth, with the largest effects in early pregnancy (14-16 weeks) (OR: 1.25 95% CI [1.04-1.50], P = 0.02) and more modest effects in later pregnancy (30-32 weeks) (OR: 1.18 95% CI [0.98-1.42], P = 0.07). With every one-point increase on the PSQI, the odds of preterm birth increase 25% in early pregnancy and 18% in later pregnancy.

CONCLUSIONS

Poor sleep quality, in both early and late pregnancy, is associated with an increased risk of delivering preterm. Currently the specific pathway(s) through which disturbed sleep contributes to PTB are unknown. We suggest that poor sleep may contribute to increased risk for PTB both independently, as well as in conjunction with other established risk factors, such as stress.

Lower genital tract inflammatory milieu and the risk of subsequent preterm birth: an exploratory factor analysis

The inflammatory milieu of the cervix may play a role in preventing intrauterine infection and subsequent preterm birth. The objectives of this study were to use exploratory factor analysis to discover the underlying structure of cytokines in the lower genital tract immunological milieu, and evaluate the association between the cytokine factors and risk of preterm birth. Women (n=613) enrolled in a prospective pregnancy cohort study in Pittsburgh, Pennsylvania had cervical cytokine concentrations assayed at <16 weeks and were followed for data on pregnancy outcomes. Principal factor analysis identified two primary cytokine patterns at <16 weeks gestation: Factor 1 (pro-inflammatory/immunomodulatory factor), which loaded highly on interleukin (IL)-1β, IL-6, IL-8, monocyte chemotactic protein-1, and IL-10, and Factor 2 (anti-inflammatory factor), which loaded heavily on IL-4, IL-10, and IL-13. Women in the highest tertile of anti-inflammatory cytokine factor scores at <16 weeks had an increased risk of spontaneous preterm birth (confounder-adjusted odds ratio [95% confidence interval]: 2.4 [1.1, 5.7]). There was no association between pro-inflammatory cytokine factor scores and preterm birth risk. These data support the hypothesis that increased concentrations of anti-inflammatory cytokines may represent a cervical immune milieu that permits subsequent microbial invasion of the uterus during pregnancy, leading to subsequent spontaneous preterm birth.

Mid-trimester cervical inflammatory milieu and sonographic cervical length

OBJECTIVE

The purpose of this study was to explore the relation between the relative balance of pro- and antiinflammatory cytokines in cervical fluid and mid-trimester cervical length.

STUDY DESIGN

In this prospective longitudinal cohort of women with a previous spontaneous preterm birth, mid-trimester cervical length ultrasound scans and cervical fluid levels were obtained serially. Multiple pro- and antiinflammatory cytokines were selected. We summed the multiples of the median for proinflammatory cytokines to generate the proinflammatory and the antiinflammatory scores. The relation between cervical length and pro-/antiinflammatory ratio was assessed by generalized estimating equations.

RESULTS

The pro-/antiinflammatory ratio had a negative linear association with cervical length (beta = -0.09; P < .001). Sixty percent of visits demonstrated greater concentrations of proinflammatory cytokines relative to antiinflammatory cytokines. This relationship did not change between first and last visits.

CONCLUSION

Among women with a previous preterm birth, shorter mid-trimester cervical length is associated with a more proinflammatory balance of cytokines in the cervical inflammatory milieu.

Metabolomics in premature labor: a novel approach to identify patients at risk for preterm delivery

OBJECTIVE

Biomarkers for preterm labor (PTL) and delivery can be discovered through the analysis of the transcriptome (transcriptomics) and protein composition (proteomics). Characterization of the global changes in low-molecular weight compounds which constitute the 'metabolic network' of cells (metabolome) is now possible by using a 'metabolomics' approach. Metabolomic profiling has special advantages over transcriptomics and proteomics since the metabolic network is downstream from gene expression and protein synthesis, and thus more closely reflects cell activity at a functional level. This study was conducted to determine if metabolomic profiling of the amniotic fluid can identify women with spontaneous PTL at risk for preterm delivery, regardless of the presence or absence of intraamniotic infection/inflammation (IAI).

STUDY DESIGN

Two retrospective cross-sectional studies were conducted, including three groups of pregnant women with spontaneous PTL and intact membranes: (1) PTL who delivered at term; (2) PTL without IAI who delivered preterm; and (3) PTL with IAI who delivered preterm. The first was an exploratory study that included 16, 19, and 20 patients in groups 1, 2, and 3, respectively. The second study included 40, 33, and 40 patients in groups 1, 2, and 3, respectively. Amniotic fluid metabolic profiling was performed by combining chemical separation (with gas and liquid chromatography) and mass spectrometry. Compounds were identified using authentic standards. The data were analyzed using discriminant analysis for the first study and Random Forest for the second.

RESULTS

(1) In the first study, metabolomic profiling of the amniotic fluid was able to identify patients as belonging to the correct clinical group with an overall 96.3% (53/55) accuracy; 15 of 16 patients with PTL who delivered at term were correctly classified; all patients with PTL without IAI who delivered preterm neonates were correctly identified as such (19/19), while 19/20 patients with PTL and IAI were correctly classified. (2) In the second study, metabolomic profiling was able to identify patients as belonging to the correct clinical group with an accuracy of 88.5% (100/113); 39 of 40 patients with PTL who delivered at term were correctly classified; 29 of 33 patients with PTL without IAI who delivered preterm neonates were correctly classified. Among patients with PTL and IAI, 32/40 were correctly classified. The metabolites responsible for the classification of patients in different clinical groups were identified. A preliminary draft of the human amniotic fluid metabolome was generated and found to contain products of the intermediate metabolism of mammalian cells and xenobiotic compounds (e.g. bacterial products and Salicylamide).

CONCLUSION

Among patients with spontaneous PTL with intact membranes, metabolic profiling of the amniotic fluid can be used to assess the risk of preterm delivery in the presence or absence of infection/inflammation.

Pro-inflammatory and anti-inflammatory cytokines in human preterm and term cervical ripening

Cervical ripening is necessary for successful delivery. Since cytokines are believed to be involved in this process, the aim of this study was to investigate possible changes in the mRNA and protein expression of pro-inflammatory cytokines (interleukin (IL)-1alpha, IL-1beta, IL-12, IL-18) and anti-inflammatory cytokines (IL-4, IL-10, IL-13) in the human cervix during pregnancy, term and preterm labor. Cervical biopsies were taken from 59 women: 21 at preterm labor, 24 at term labor, 10 at term not in labor and 4 from non-pregnant women. mRNA was analyzed with real-time RT-PCR and protein expression and/or secretion with immunohistochemistry and ELISA. There was an upregulation of mRNA for IL-10, IL-13, IL-1alpha and IL-1beta in the laboring groups, while mRNA for IL-12 and IL-18 was downregulated. IL-4 mRNA was detected more frequently, while IL-12 mRNA expression was lower, in the preterm labor group than in the term labor group. The protein levels of IL-4 and IL-12 were lower and IL-18 tended to be higher in the labor groups, while IL-10 protein levels were unaffected by labor. IL-4 protein levels were significantly higher in the preterm subgroup with bacterial infection than in the non-infected group. IL-10 had higher expression in squamous epithelium at preterm labor than at term. In conclusion, the major changes in pro-inflammatory and anti-inflammatory cytokine mRNA and protein expression in cervix occur during the labor process irrespective of the length of gestation. Our results indicate that dysregulation of anti-inflammatory cytokines in the human cervix could be involved in the pathogenesis of preterm labor.