Clinical risk factors for vasculo-placental disorders: results from a prospective case-control study nested in HEMOTHEPP French cohort study.

OBJECTIVE: Determine clinical risk factors for vasculo-placental disorders in singleton pregnancies. DESIGN: Prospective case-control study nested in HEMOTHEPP French cohort. SETTING: Women delivered between June, 2015 and January, 2019 in any maternity ward of Finistère. POPULATION: Cases were women with vasculo-placental disorders (pre-eclampsia, intrauterine growth restriction (IUGR), placental abruption or stillbirth). Controls were women matched for age at delivery and parity. METHODS: Clinical data were collected by obstetricians or midwives during antenatal care visits and delivery, and recorded by trained research assistants. MAIN OUTCOME MEASURES: Occurrence of a vasculo-placental disorder. RESULTS: 505 women with vasculo-placental disorder (299 pre-eclampsia, 253 IUGR, 44 placental abruptions, 11 stillbirths) and 1515 matched controls were selected out of 20,075 participants. In multivariable analysis, four clinical parameters were associated with pre-eclampsia: obesity (Odd ratio (OR) = 3.11, 95%CI 2.11-4.58), French overseas origin (OR = 4.41, 95%CI 1.87-10.42), previous vasculo-placental disorder (OR = 5.14, 95%CI 2.72-9.70), aspirin during pregnancy (OR = 10.10, 95%CI 1.99-51.08). Three clinical parameters were associated with IUGR: auto-immune/inflammatory disorder (OR = 3.75, 95%CI 1.83-7.68), previous vasculo-placental disorder (OR = 3.63, 95%CI 2.06-6.41), smoking during pregnancy (OR = 2.66, 95%CI 1.91- 3.71). A previous venous thromboembolism (VTE) was associated with IUGR in univariable but not in multivariable analysis (OR = 3.72, 95%CI 0.82-17.00, p = 0.09). CONCLUSIONS: Clinical risk factors differ between IUGR and pre-eclampsia, the later, but not the former, being associated with cardiovascular risk factors.

Family history of postpartum hemorrhage is a risk factor for postpartum hemorrhage after vaginal delivery: results from the French prospective multicenter Haemorrhages and Thromboembolic Venous Disease of the Postpartum cohort study.

BACKGROUND: Postpartum hemorrhage is a major component of perinatal morbidity and mortality that affects young women worldwide and is still often unpredictable. Reducing the incidence of postpartum hemorrhage is a major health issue and identifying women at risk for postpartum hemorrhage is a key element in preventing this complication. OBJECTIVE: This study aimed to estimate postpartum hemorrhage prevalence after vaginal delivery and to identify postpartum hemorrhage risk factors. STUDY DESIGN: Unselected pregnant women ≥16 years of age admitted to 1 of 6 maternity wards in Brittany (France) for vaginal birth after 15 weeks of gestation were recruited in this prospective, multicenter cohort study between June 1, 2015, and January 31, 2019. Postpartum hemorrhage was defined as blood loss ≥500 mL in the 24 hours following delivery. Independent risk factors for postpartum hemorrhage were determined using logistic regression. Missing data were imputed using the Multivariate Imputation by Chained Equations method. RESULTS: Among 16,382 included women, the postpartum hemorrhage prevalence was 5.37%. A first-degree family history of postpartum hemorrhage (adjusted odds ratio, 1.63; 95% confidence interval, 1.24-2.14) and a personal transfusion history (adjusted odds ratio, 1.90; 95% confidence interval, 1.23-2.92) were significantly associated with postpartum hemorrhage. The use of oxytocin during labor was also a risk factor for postpartum hemorrhage (adjusted odds ratio, 1.24; 95% confidence interval, 1.06-1.44). Inversely, smoking during pregnancy and intrauterine growth restriction were associated with a reduced risk for postpartum hemorrhage (adjusted odds ratio, 0.76; 95% confidence interval, 0.63-0.91, and 0.34; 95% confidence interval, 0.13-0.87, respectively). CONCLUSION: In addition to classical risk factors, this study identified a family history of postpartum hemorrhage and personal transfusion history as new characteristics associated with postpartum hemorrhage after vaginal delivery. The association of postpartum hemorrhage with a family history of postpartum hemorrhage suggests a hereditary hemorrhagic phenotype and calls for genetic studies. Identifying women at risk for postpartum hemorrhage is a key element of being prepared for this complication.

Development and Validation of a Predictive Tool for Postpartum Hemorrhage after Vaginal Delivery: A Prospective Cohort Study.

Postpartum hemorrhage (PPH) is one of the leading causes of maternal morbidity worldwide. This study aimed to develop and validate a predictive model for PPH after vaginal deliveries, based on routinely available clinical and biological data. The derivation monocentric cohort included pregnant women with vaginal delivery at Brest University Hospital (France) between April 2013 and May 2015. Immediate PPH was defined as a blood loss of ≥500 mL in the first 24 h after delivery and measured with a graduated collector bag. A logistic model, using a combination of multiple imputation and variable selection with bootstrap, was used to construct a predictive model and a score for PPH. An external validation was performed on a prospective cohort of women who delivered between 2015 and 2019 at Brest University Hospital. Among 2742 deliveries, PPH occurred in 141 (5.1%) women. Eight factors were independently associated with PPH: pre-eclampsia (aOR 6.25, 95% CI 2.35−16.65), antepartum bleeding (aOR 2.36, 95% CI 1.43−3.91), multiple pregnancy (aOR 3.24, 95% CI 1.52−6.92), labor duration ≥ 8 h (aOR 1.81, 95% CI 1.20−2.73), macrosomia (aOR 2.33, 95% CI 1.36−4.00), episiotomy (aOR 2.02, 95% CI 1.40−2.93), platelet count < 150 Giga/L (aOR 2.59, 95% CI 1.47−4.55) and aPTT ratio ≥ 1.1 (aOR 2.01, 95% CI 1.25−3.23). The derived predictive score, ranging from 0 to 10 (woman at risk if score ≥ 1), demonstrated a good discriminant power (AUROC 0.69; 95% CI 0.65−0.74) and calibration. The external validation cohort was composed of 3061 vaginal deliveries. The predictive score on this independent cohort showed an acceptable ability to discriminate (AUROC 0.66; 95% CI 0.62−0.70). We derived and validated a robust predictive model identifying women at risk for PPH using in-depth statistical methodology. This score has the potential to improve the care of pregnant women and to take preventive actions on them.