Preterm preeclampsia as an independent risk factor for thromboembolism in a large national cohort

BACKGROUND

Preterm preeclampsia, a product of vascular dysfunction, is associated with prolonged hospital admission and proteinuria, significant risk factors for thromboembolism in pregnancy. The risk of thromboembolism in preterm preeclampsia warrants further investigation.

OBJECTIVE

To determine the relationship between preterm preeclampsia and thromboembolic risk. We hypothesize that preterm preeclampsia is an independent risk factor for thromboembolism in pregnancy.

STUDY DESIGN

This is a retrospective cohort study using the National Inpatient Sample database via Healthcare Cost and Utilization Project-Agency for Healthcare Cost and Utilization Project from 2017-2019. All subjects with an International Classification of Diseases, Tenth Revision code for pregnancy or peripartum encounter were included. Subjects were excluded if the gestational age at delivery was <20 weeks or if they had a history of thromboembolism, inherited thrombophilia, or antiphospholipid syndrome. Patients with preterm (delivered <37 weeks) preeclampsia and term (delivered ≥37 weeks) preeclampsia were compared with those without preeclampsia. The primary outcome was a composite of any thromboembolic event, including pulmonary embolism, deep vein thrombosis, cerebral thrombosis or transient ischemic attack, or other thromboses. The secondary outcomes were rates of each type of thromboembolic event. The groups were compared via variance analysis, chi-square, and logistic regression analyses. The logistic regression included those variables that differed between groups with P<.05.

RESULTS

Of individuals in the database, >2.2 million met the inclusion criteria. A total of 56,446 (2.7%) had preterm preeclampsia, and 86,152 (6.7%) had term preeclampsia. Those with preterm preeclampsia were more likely to be older, identify as non-Hispanic black, have obesity, have chronic hypertension among other chronic diseases, and be in the lowest quartile of income (P<.001). Among patients with preterm preeclampsia, 0.32% experienced thromboembolism, whereas those with term preeclampsia and without preeclampsia experienced thromboembolism at 0.10% and 0.09%, respectively. After controlling for confounders that differed between groups with P<.05, preterm preeclampsia remained independently associated with any thromboembolic event (adjusted odds ratio, 2.21 [95% confidence interval, 1.84-2.65]), and each type of thromboembolism. Term preeclampsia was not associated with an increased risk of thromboembolism (adjusted odds ratio, 1.18 [95% confidence interval, 0.94-1.48]).

CONCLUSION

Preterm preeclampsia is independently associated with an increased risk of thromboembolic events.

Safety of pregnancy after cerebral venous thrombosis: A case-control study

Background and Aims

Since pregnancy is considered one of the major risk factors of cerebral venous thrombosis (CVT), the safety of pregnancy in women of childbearing age and a previous history of CVT, is concerning in terms of prevention, family planning, and management. This study aims to estimate the prevalence of pregnancies among women of childbearing age with previous CVT, evaluate the pregnancy-associated risk of CVT recurrence, and explore the maternal and fetal outcomes among CVT women in comparison with pregnant women without a history of CVT.

Methods

A retrospective, case-control study was conducted at the Obstetrics Departments of King Fahad Medical City Hospital, Saudi Arabia. It included all women with a history of CVT diagnosed in the last 5 years (cases), as well as CVT history-free pregnant women (control). The prevalence of pregnancy after CVT was estimated and the prepartum and postpartum parameters of the two groups were compared.

Results

Fifty women with CVT and 100 controls were included. Among the 50 CVT cases, 28 (56.0%) have been pregnant. The incidence of pre-eclampsia was significantly more frequent in CVT women (7.1% vs. 0.0%, p = 0.047); however, only one case of deep vein thrombosis (3.6%) was reported in CVT patients versus none in controls (p = 0.219). CVT women delivered at a lower gestational age (mean [SD] = 36.9 [3.5] weeks) compared with controls (38.3 [1.4] weeks) (p = 0.006). No significant differences in other pregnancy or delivery outcomes were observed between the two groups.

Conclusion

More than half of women of childbearing age with a history of CVT opt for pregnancy after the CVT episode, with no major additional risk for pre or postpartum complications.

Trimester-specific reference intervals and profile of coagulation parameters for Chinese pregnant women with diverse demographics and obstetric history: a cross-sectional study

BACKGROUND

Owing to the changes in childbirth policy in China, this work aimed to update the trimester-specific reference intervals (RIs) for Chinese pregnant women with diverse demographics and obstetric history. This study also investigated how advanced maternal age (AMA) (> 35 years old), gravity, and parity influence gestational coagulation parameters.

METHODS

In this prospective cross-sectional study, five coagulation parameters were measured using assays provided by Roche diagnostics on Cobas t 711: prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fib), and D-dimer, and the trimester-specific 2.5th -97.5th and 95th (D-dimer only) percentiles RIs were established accordingly. Linear regressions were undertaken to analyze the association with demographic characteristics and obstetric history for each parameter.

RESULTS

893 eligible pregnant women in different trimesters and at AMA/non-AMA and 275 non-pregnant healthy women were enrolled. For the first, second, and third trimester, respectively, RIs were as follows: APTT (s): 24.8-35.7, 24.6-34.1, and 23.5-34.7; TT (s): 14.4-17.3, 14.1-16.7, and 14.2-17.5; PT (s): 8.30-10.20, 8.00-9.77, and 7.92-9.57; PT-INR: 0.86-1.06, 0.83-1.02, and 0.82-0.98; Fib (g/L): 2.76-4.97, 3.14-5.31, and 3.44-5.93; D-dimer (µg/ml): 0-0.969, 0-2.14, and 0-3.28. No statistically significant differences were observed in TT, D-dimer, and APTT between the AMA and non-AMA women, while PT and PT-INR were shorter and Fib was higher in the AMA group. The association of gravidity and parity with each coagulation parameter is statistically significant (p < 0.05). PT and PT-INR were shortened and D-dimer decreased as gravidity increased. Longer PT and PT-INR, shorter APPT, higher D-Dimer, and lower Fib were associated with increasing parity.

CONCLUSIONS

This work updated the gestational coagulation profiles of Chinese pregnant women and established trimester-specific RIs accordingly. Establishing specific RIs based on AMA, parity, and gravidity might not be necessary.

Optimal Endometrial Preparation Protocols for Frozen-thawed Embryo Transfer Cycles by Maternal Age

This retrospective cohort study aimed to explore the optimal endometrial preparation protocols among different maternal age groups. A total of 16,867 frozen-thawed embryo transfer (FET) cycles were categorized into three groups based on endometrial preparation protocols: Natural cycle (NC n = 3893), artificial cycles (AC, n = 11456) and AC with GnRH-a pretreatment (AC+GnRH-a, n = 1518). To account for repeat cycles, a generalized estimating equation (GEE) method was applied to examine the associations between cycle regimens and pregnancy outcomes. Subgroup analyses were conducted to evaluate the best preparation methods for different maternal age groups. Primary outcomes were live birth and early miscarriage rates. After completing GEE, in overall population, the live birth rate [(NC as reference; AC: adjusted odds ratio (aOR) = 0.837, 95% confidential interval (CI) 0.771-0.908; AC+GnRHa: aOR = 0.906, 95%CI 0.795-1.031)] in NC was significantly higher than that in AC, while comparable that in AC+GnRH-a. The early miscarriage rate (AC: aOR = 1.420, 95%CI 1.225-1.646; AC+GnRHa: aOR = 1.545, 95%CI 1.236-1.931) was significantly lower in NC compared to either AC group. Subgroup analysis showed that in younger women, the incidences of live birth (AC: aOR = 0.900, 95%CI 0.804-1.007; AC+GnRHa: aOR = 1.091, 95%CI 0.904-1.317) were equivalent between groups, with a slightly higher in AC+GnRH-a. Early miscarriage rate (AC: aOR = 1.462, 95%CI 1.165-1.835; AC+GnRHa: aOR = 1.137, 95%CI 0.948-1886) was only significantly lower in NC compared to that in AC. In older women, the live birth rate (AC: aOR = 0.815, 95%CI 0.722-0.920; AC+GnRHa: aOR = 0.759, 95%CI 0.627-0.919) was significantly higher, and early miscarriage rate (AC: aOR = 1.353, 95%CI 1.118-1.638; AC+GnRHa: aOR = 1.704, 95%CI 1.273-2.280) was significantly lower in NC compared to either AC group. Our study demonstrated that NC is associated with lower early miscarriage late in overall IVF population. There is a mild favor of AC+GnRH-a in younger women, while the priority of NC is remarkable in older women. Maternal age should be a considerable factor when determining endometrial preparation method for FET.

Complications of Cesarean Birth: Clinical Recommendations for Prevention and Management

The increase in severe maternal morbidity and mortality in the United States correlates with a significant rise in U.S. cesarean birth rates from 5.5% in 1970 to a rate of 31.9% of all births in 2018, far beyond the World Health Organization goal of 10% to 15%. Three key contributors to maternal morbidity and mortality related to cesarean birth include complications of hemorrhage, surgical site infection, and venous thromboembolism. All women should be screened for risk factors associated with these major complications during the antepartum, intrapartum, and postpartum period to assure the availability of immediate resources based on the assessment. Implementing evidence-based maternity care safety bundles, toolkits, and protocols to manage these complications can reduce adverse outcomes.

Acute phase treatment of VTE: Anticoagulation, including non-vitamin K antagonist oral anticoagulants

The acute phase of venous thromboembolism (VTE) treatment focuses on the prompt and safe initiation of full-dose anticoagulation to decrease morbidity and mortality. Immediate management consists of resuscitation, supportive care, and thrombolysis for patients with haemodynamically significant pulmonary embolism (PE) or limb-threatening deep-vein thrombosis (DVT). Patients with contraindications to anticoagulants are considered for vena cava filters. Disposition for the acute treatment of VTE is then considered based on published risk scores and the patient's social status, as the first seven days carries the highest risk for VTE recurrence, extension and bleeding due to anticoagulation. Next, a review of: immediate and long-term bleeding risk, comorbidities (i. e. active cancer, renal failure, obesity, thrombophilia), medications, patient preference, VTE location and potential for pregnancy should be undertaken. This will help determine the most suitable anticoagulant for immediate treatment. The non-vitamin K antagonist oral anticoagulants (NOACs), including the factor Xa inhibitors apixaban, edoxaban and rivaroxaban as well as the direct-thrombin inhibitor dabigatran, are increasing the convenience of and options available for VTE treatment. Current options for immediate treatment include low-molecular-weight heparin (LMWH), unfractionated heparin (UFH), fondaparinux, apixaban, or rivaroxaban. LMWH or UFH may be continued as monotherapy or transitioned to treatment with a VKA, dabigatran or edoxaban. This review describes the upfront treatment of VTE and the evolving role of NOACs in the contemporary management of VTE.