The 'onion skin' sign of a low-grade appendiceal mucinous neoplasm: An incidental finding during early pregnancy assessment.

A low-grade appendiceal mucinous neoplasm (LAMN) is a cystic dilatation of the appendix resulting from the accumulation of mucinous secretions caused by a luminal obstruction. Although usually benign, pseudomyxoma peritonei may occur in the event of rupture, and 10% of cases may be secondary to appendiceal cystadenocarcinoma. A LAMN is both more common and more likely to have a malignant association in women, making it an entity with which practitioners of gynaecological ultrasound should be familiar. Although not the primary aim, early pregnancy ultrasound assessments can offer the diagnostic opportunity to identify pelvic pathology. A LAMN can be identified on ultrasonography by visualisation of an adnexal mass separate to the ovary, which due to the layers of secretions has a distinctive appearance previously likened to 'onion-skin' or 'whipped-cream'. Here, we describe an incidental finding of a LAMN during an early pregnancy assessment. Practitioners of early pregnancy ultrasound should be familiar with the characteristic morphology of this rare but important finding.

Using simple clinical and ultrasound variables to develop a model to predict first trimester pregnancy viability.

INTRODUCTION: Early prediction of pregnancies destined to miscarry will allow couples to prepare for this common but often unexpected eventuality, and clinicians to allocate finite resources. We aimed to develop a prediction model combining clinical, demographic, and sonographic data as a clinical tool to aid counselling about first trimester pregnancy outcome. MATERIAL AND METHODS: This is a prospective, observational cohort study conducted at Queen Charlotte's and Chelsea Hospital, UK from March 2014 to May 2019. Women with confirmed intrauterine pregnancies between 5 weeks and their dating scan (11-14 weeks) were recruited. Participants attended serial ultrasound scans in the first trimester and at each visit recorded symptoms of vaginal bleeding, pelvic pain, nausea and vomiting using validated scoring tools. Pregnancies were followed up until the dating scan (11-14 weeks). Univariate and multivariate analyses were performed to predict first trimester viability. A model was developed with multivariable logistic regression, variables limited by feature selection, and bootstrapping with multiple imputation was used for internal validation. RESULTS: 1403 women were recruited and after exclusions, data were available for 1105. 160 women (14.5 %) experienced first trimester miscarriage and 945 women (85.5 %) had viable pregnancies at 11-14 weeks' gestation. The average gestational age at the initial visit (calculated from the menstrual dates) was 7 + 1 weeks (+/-12.2 days). A multivariable logistic regression model was developed to predict first trimester viability and included the variables: mean gestational sac diameter, presence of fetal heart pulsations, difference in gestational age from last menstrual period and from mean sac diameter on ultrasonography, current folic acid usage and maternal age. The model demonstrated good performance (optimism-corrected area under curve (AUC) 0.84, 95 % CI 0.81-0.87; optimism-corrected calibration slope 0.969). CONCLUSION: We have developed and internally validated a model to predict first trimester viability with good accuracy prior to the 11-14 week dating scan, which now needs to be externally validated prior to clinical use.

Safe Service Delivery of a Complex Early Pregnancy Problem: Caesarean Scar Pregnancy.

Caesarean Scar Pregnancy (CSP) is an ectopic pregnancy with implantation into the niche of the uterine scar. We aimed to describe the local management of consecutive cases of CSP to develop a standard operating procedure (SOP). Between December 2019 and June 2022, there were 19,100 maternities. Of these, 23 were CSPs in 19 patients. Median BMI was 29 (range 20.5-52), median number of Caesarean deliveries (CS) was 2 (range 1-4) and 7/23 (30%) were cigarette smokers. At diagnosis, 9/23 were live pregnancies, 3/23 were retained products of conception (RPOC), 9/23 were pregnancies of uncertain viability (PUV), and 2/23 were non-viable. In six, the initial management was expectant, surgical suction evacuation with transrectal ultrasound guidance in 16, and one had a hysterectomy. The median blood loss was 100 mL (range 50-2000 mL). Two patients (9%) required a blood transfusion. Median hospital stay was 1 day (range 0-4). At follow-up after 10 weeks, no patients had an ongoing haematoma, and one had significant RPOC electing hysterectomy. Eight women were known to have 9 subsequent pregnancies (recurrent CSP n = 4, livebirth n = 2, miscarriage n = 2, tubal ectopic n = 1). Outcomes as rated by low blood loss, short hospital stay, and rare need for further intervention were favorable. Factors associated included prompt ultrasonographic diagnosis, availability of transrectal ultrasound guided surgery, and specialist follow-up, which form the basis of the SOP.

Changes in Circulating Kisspeptin Levels During Each Trimester in Women With Antenatal Complications.

CONTEXT: Antenatal complications such as hypertensive disorders of pregnancy (HDP), fetal growth restriction (FGR), gestational diabetes (GDM), and preterm birth (PTB) are associated with placental dysfunction. Kisspeptin has emerged as a putative marker of placental function, but limited data exist describing circulating kisspeptin levels across all 3 trimesters in women with antenatal complications. OBJECTIVE: We aimed to assess whether kisspeptin levels are altered in women with antenatal complications. METHODS: Women with antenatal complications (n = 105) and those with uncomplicated pregnancies (n = 265) underwent serial ultrasound scans and blood sampling at the Early Pregnancy Assessment Unit at Hammersmith Hospital, UK, at least once during each trimester (March 2014 to March 2017). The women with antenatal complications (HDP [n = 32], FGR [n = 17], GDM [n = 35], PTB [n = 11], and multiple complications [n=10]) provided 373 blood samples and the controls provided 930 samples. Differences in circulating kisspeptin levels were assessed. RESULTS: Third-trimester kisspeptin levels were higher than controls in HDP but lower in FGR. The odds of HDP adjusted for gestational age, maternal age, ethnicity, BMI, smoking, and parity were increased by 30% (95% CI, 16%-47%; P < 0.0001), and of FGR were reduced by 28% (95% CI, 4-46%; P = 0.025), for every 1 nmol/L increase in plasma kisspeptin. Multiple of gestation-specific median values of kisspeptin were higher in pregnancies affected by PTB (P = 0.014) and lower in those with GDM (P = 0.020), but not significantly on multivariable analysis. CONCLUSION: We delineate changes in circulating kisspeptin levels at different trimesters and evaluate the potential of kisspeptin as a biomarker for antenatal complications.

Gradient boosted trees with individual explanations: An alternative to logistic regression for viability prediction in the first trimester of pregnancy.

BACKGROUND: Clinical models to predict first trimester viability are traditionally based on multivariable logistic regression (LR) which is not directly interpretable for non-statistical experts like physicians. Furthermore, LR requires complete datasets and pre-established variables specifications. In this study, we leveraged the internal non-linearity, feature selection and missing values handling mechanisms of machine learning algorithms, along with a post-hoc interpretability strategy, as potential advantages over LR for clinical modeling. METHODS: The dataset included 1154 patients with 2377 individual scans and was obtained from a prospective observational cohort study conducted at a hospital in London, UK, from March 2014 to May 2019. The data were split into a training (70%) and a test set (30%). Parsimonious and complete multivariable models were developed from two algorithms to predict first trimester viability at 11-14 weeks gestational age (GA): LR and light gradient boosted machine (LGBM). Missing values were handled by multiple imputation where appropriate. The SHapley Additive exPlanations (SHAP) framework was applied to derive individual explanations of the models. RESULTS: The parsimonious LGBM model had similar discriminative and calibration performance as the parsimonious LR (AUC 0.885 vs 0.860; calibration slope: 1.19 vs 1.18). The complete models did not outperform the parsimonious models. LGBM was robust to the presence of missing values and did not require multiple imputation unlike LR. Decision path plots and feature importance analysis revealed different algorithm behaviors despite similar predictive performance. The main driving variable from the LR model was the pre-specified interaction between fetal heart presence and mean sac diameter. The crown-rump length variable and a proxy variable reflecting the difference in GA between expected and observed GA were the two most important variables of LGBM. Finally, while variable interactions must be specified upfront with LR, several interactions were ranked by the SHAP framework among the most important features learned automatically by the LGBM algorithm. CONCLUSIONS: Gradient boosted algorithms performed similarly to carefully crafted LR models in terms of discrimination and calibration for first trimester viability prediction. By handling multi-collinearity, missing values, feature selection and variable interactions internally, the gradient boosted trees algorithm, combined with SHAP, offers a serious alternative to traditional LR models.

Performance of plasma kisspeptin as a biomarker for miscarriage improves with gestational age during the first trimester.

OBJECTIVE: To compare the performance of kisspeptin and beta human chorionic gonadotropin (ßhCG), both alone and in combination, as biomarkers for miscarriage throughout the first trimester. DESIGN: Prospective, nested case-control study. SETTING: Tertiary Centre, Queen Charlotte Hospital, London, United Kingdom. PATIENT(S): Adult women who had miscarriages (n = 95, 173 samples) and women with healthy pregnancies (n = 265, 557 samples). INTERVENTION(S): The participants underwent serial ultrasound scans and blood sampling for measurement of plasma kisspeptin and ßhCG levels during the first trimester. MAIN OUTCOME MEASURE(S): The ability of plasma kisspeptin and ßhCG levels to distinguish pregnancies complicated by miscarriage from healthy pregnancies unaffected by miscarriage. RESULT(S): Gestation-adjusted levels of circulating kisspeptin and ßhCG were lower in samples from women with miscarriages than in women with healthy pregnancies by 79% and 70%, respectively. The area under the receiver-operating characteristic curve for identifying miscarriage during the first trimester was 0.874 (95% confidence interval [CI] 0.844-0.904) for kisspeptin, 0.859 (95% CI 0.820-0.899) for ßhCG, and 0.916 (95% CI 0.886-0.946) for the sum of the two markers. The performance of kisspeptin in identifying miscarriage improved with increasing length of gestation, whereas that of ßhCG worsened. A decision matrix incorporating kisspeptin, ßhCG, and gestational age had 83% to 87% accuracy for the prediction of miscarriage. CONCLUSION(S): Plasma kisspeptin is a promising biomarker for miscarriage and provides additional value to ßhCG alone, especially during later gestational weeks of the first trimester.