O-129 Lactobacillus deplete vaginal microbial composition is associated with chromosomally normal miscarriage and local inflammation

Study question

To investigate the vaginal microbial composition and the local immune response in chromosomally normal and abnormal miscarriages and compare this to uncomplicated pregnancies delivering at term.

Summary answer

We show that euploid miscarriage is associated with a significantly higher prevalence of Lactobacillus spp. deplete vaginal microbial communities compared to aneuploid miscarriage.

What is known already

Emerging evidence supports the role of the vaginal microbiota in adverse pregnancy outcome, but the underlying mechanisms are poorly understood. A dominance of Lactobacillus spp. in pregnancy provides protection against pathogenic bacteria by producing lactic acid and antimicrobial compounds. A depletion in Lactobacillus spp. is often linked to adverse pregnancy outcomes.Current work also implicates the reproductive tract microbiota as a key modulator of local inflammatory and immune pathways. We have previously shown that miscarriage is associated with vaginal dysbiosis but without knowledge of the cytogenetic status of those miscarriages or the local immune profile.

Study design, size, duration

This study was a prospective observational cohort study based at Queen Charlotte’s & Chelsea Hospital, Early Pregnancy Unit, London between March 2014-February 2019. Vaginal swabs were collected from the posterior vaginal fornix of 167 patients.

Participants/materials, setting, methods

We used 16S rRNA gene based metataxonomics to interrogate the vaginal microbiota in a cohort of 167 women, 93 miscarriage patients (54 euploid and 39 aneuploid using molecular cytogenetics) and 74 women who delivered at term and correlate this with the aneuploidy status of the miscarriages. We also measured the concentrations of IL-2, IL-4, IL-6, IL-8, TNF-α, IFN-γ, IL-1β, IL-18 and IL-10 in cervical vaginal fluid using Human Magnetic Luminex Screening Assay (8-plex).

Main results and the role of chance

We show that euploid miscarriage is associated with a significantly higher prevalence of Lactobacillus spp. deplete vaginal microbial communities compared to aneuploid miscarriage (P=0.008). In women having Lactobacillus spp. deplete vaginal microbial communities, euploid miscarriage associates with higher concentrations of pro-inflammatory cytokines IL-1β, IL-8, IL-6 (P<0.001, P=0.01 and P<0.001 respectively) and lower concentrations of anti-inflammatory cytokines IL10 (P<0.001) when compared to viable term pregnancy. We identified Prevotella bivia and Streptococcus as particularly common in euploid miscarriage and as drivers of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α). Co-occurrence network analyses revealed low levels of co-occurrence between Lactobacillus crispatus and other organisms and strong co-occurrence between Streptococcal species. Our data show a combination of both an adverse vaginal microbiota and a cytokine response to it influences early pregnancy outcome. Although this may be a reflection of intrinsic maternal immune response, it appears that the cytokine response is largely driven by the bacterial taxa present in the vagina, which presents an opportunity for specific, directed intervention. The negative co-occurrence between L.crispatus and all other organisms suggests a possible therapeutic role for probiotics containing this organism. The influence of Streptococci also suggests a potential benefit of targeted antibiotics with probiotics for some patients.

Limitations, reasons for caution

There were no longitudinal samples in this cohort and our results are based on the assumption that the vaginal microbial composition is stable throughout the first trimester.Future longitudinal studies with larger sample sizes are needed to corroborate these findings and provide insights to the mechanisms that trigger the inflammatory response.

Wider implications of the findings

These findings support the hypothesis that the vaginal microbiota plays an important aetiological role in euploid miscarriage and may represent a target to modify the risk of pregnancy loss.

Trial registration number

n/a

Natural history of pregnancy-related enhanced myometrial vascularity following miscarriage

OBJECTIVES

Our primary aim was to report the incidence of enhanced myometrial vascularity (EMV) in consecutive women attending our early pregnancy assessment unit, following first-trimester miscarriage. We aimed further to evaluate the clinical presentation and complications associated with expectant and surgical management of EMV in these women.

METHODS

This was a prospective cohort study conducted in a London teaching hospital between June 2015 and June 2018, including consecutive patients with an observation of EMV on transvaginal ultrasonography following first-trimester miscarriage. The diagnosis was made following the subjective identification of EMV using color Doppler ultrasonography and a peak systolic velocity (PSV) ≥ 20 cm/s within the collection of vessels. Women were followed up with repeat scans every 14 days. Management was expectant unless intervention was indicated because of excessive or prolonged bleeding, persistent presence of retained tissue in the endometrial cavity or patient choice. The final clinical outcome was recorded. Time to resolution of EMV was defined as the interval from detection of EMV until resolution.

RESULTS

During the study period, there were 2627 first-trimester fetal losses in the department and, of these, 40 patients were diagnosed with EMV, hence the incidence of EMV following miscarriage was 1.52%. All cases were associated with ultrasound evidence of retained products of conception (RPOC) at presentation (mean dimensions, 22 × 20 × 20 mm). Thirty-one patients opted initially for expectant management, of which 18 had successful resolution without intervention, five were lost to follow-up and eight subsequently had surgical evacuation due to patient choice. No expectantly managed case required emergency intervention. Nine patients chose surgical evacuation as primary treatment. No significant correlation was seen between PSV within the EMV at presentation and blood loss at surgery. Median PSV was 47 (range, 20-148) cm/s. The estimated blood loss in all cases managed surgically ranged from 20-300 mL. Presence of RPOC was confirmed in all specimens that were sent for analysis following surgery. For cases successfully managed expectantly, the mean time to resolution was 48 (range, 21-84) days. In the nine cases managed surgically from the beginning, the mean time to resolution of EMV was 10.6 (range, 3-29) days.

CONCLUSIONS

This study suggests that EMV is an uncommon finding following miscarriage and is associated with the presence of RPOC. Expectant management was a safe option in our cohort, with minimal bleeding, although it was associated with protracted time to resolution. In patients who opted for surgery, the maximum blood loss was 300 mL and no patient required blood transfusion or embolization. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Peripheral bone mineral density and its predictors in healthy school girls from two different socioeconomic groups in Delhi

Peripheral bone density measurements are scarce and the factors, which predict bone mineral density at these sites, especially in children, are not clearly known. In this study, age, height, weight and alkaline phosphatase had a significant association on peripheral bone mineral density in healthy Indian school girls.

INTRODUCTION

Factors that lead to the attainment of peak bone mass at peripheral sites, during period of growth are not clearly known.

METHODS

Six-hundred and sixty-four randomly selected 7- to 17-year-old girls from upper and lower socioeconomic status (USES/LSES) schools were assessed clinically and a recording of their height and weight was undertaken. Serum calcium, phosphorus, total alkaline phosphatase (ALP), 25-hydroxyvitamin D (25-OHD) and parathyroid hormone (PTH) were measured in all of them. Bone mineral density (BMD) was measured at the distal forearm (BMDdf) and calcaneum (BMDca) by peripheral dual energy X-ray absorptiometry (pDXA).

RESULTS

Girls belonging to the USES were significantly taller (149.7 +/- 12.3 cm vs 144.4 +/- 11.9 cm; P < 0.001) and weighed more (44.3 +/- 12.9 kg vs 35.9 +/- 10.0 kg; P < 0.001) than girls from the LSES. USES girls had a significantly higher mean serum calcium (9.3 +/- 0.7 mg/dl vs 9.2 +/- 0.8 mg/dl; P < 0.05) and significantly lower alkaline phosphatase (316 +/- 166 IU/l vs 423 +/- 228 IU/l; P < 0.01) and iPTH (29.9 +/- 18.4 pg/ml vs 45.7 +/- 64.6 pg/ml; P < 0.01). There was no significant difference in mean serum phosphorus and 25-OHD levels between the two groups. USES subjects had higher BMD at both sites than LSES subjects. BMDdf and BMDca increased with age and tended to plateau by 16 years and 12 years of age respectively in both the groups. Age, height and weight explained approximately 50% of the variability, while biochemical parameters explained approximately 30% of variability in BMD at both the sites. The only biochemical parameter which had a significant association with BMD was ALP at the distal forearm.

CONCLUSION

In conclusion, age, nutrition, height and weight are significantly associated with BMD at peripheral sites.

Facilitation of laryngeal mask airway insertion: effects of remifentanil administered before induction with target-controlled propofol infusion

Eighty-six adult day-case patients were recruited into a prospective, randomised study and allocated to one of two groups. Patients received either intravenous remifentanil 0.3 microg.kg(-1) or an equivalent volume of sodium chloride 0.9% followed by induction of anaesthesia with propofol target-controlled infusion until the effect (brain) site calculated concentration was 2 microg.ml(-1). Jaw opening and ease of laryngeal mask insertion were assessed immediately after mask insertion. A higher incidence of failure of induction of anaesthesia was observed in the control group compared with the remifentanil group [15 (35%) vs. 3 (7%); p < 0.01] and addition of remifentanil significantly increased the ease and success of laryngeal mask insertion, with grade 1 (no coughing/gagging) conditions observed in 29 (68%) of the remifentanil group and 21 (49%) of the control group (p < 0.01). The doses of remifentanil and propofol used were not associated with any significant cardiorespiratory instability. In conclusion, when combined with propofol target-controlled infusion, remifentanil 0.3 microg.kg(-1) facilitates laryngeal mask insertion with minimal adverse haemodynamic changes.