Pregnancy-associated mortality due to cardiovascular disease: Impact of hypertensive disorders of pregnancy

Ischemic Placental Disease: Epidemiology and Impact on Maternal and Offspring Health Along the Life Course

Ischemic placental disease (IPD) is a constellation of obstetrical complications that include preeclampsia, placental abruption, and fetal growth restriction and affects 12% to 15% of pregnancies. The unifying pathophysiological mechanism that precedes all 3 complications is uteroplacental ischemia as a consequence of inadequate (or failure of) physiological transformation of the maternal uterine spiral arteries, endothelial cell dysfunction, and increased oxidative stress. This review summarizes the IPD literature, focusing on the epidemiology and risk factors, the effects of IPD on short and long-term maternal complications, and the association of IPD with perinatal, childhood, and long-term complications in offspring.

Hospitalization for cardiovascular disease in the year after delivery of twin pregnancies

BACKGROUND AND AIMS

Increased cardiovascular demand in twin pregnancies, even those without hypertensive disease of pregnancy (HDP), may pose a greater risk for cardiovascular complications compared with singletons. In this study, the risk of cardiovascular disease (CVD)-related hospitalizations and mortality within the year following delivery in relation to HDP was compared between twin and singleton pregnancies.

METHODS

Using the Nationwide Readmissions Database of US hospitals from 2010 to 2020, the rates of CVD readmission in four exposure groups (twin deliveries with and without HDP and singleton deliveries with and without HDP) were estimated. Cox proportional hazard regression models were used to determine associations with singletons without HDP as the reference.

RESULTS

Of 36 million delivery hospitalizations, the rates of CVD readmission in twin and singleton pregnancies were 1105.4 and 734.1 per 100 000 delivery admissions, respectively. Compared with singletons without HDP, the adjusted hazard ratio (HR) of CVD readmission was highest for twins with HDP [HR 8.21, 95% confidence interval (CI) 7.48-9.01], followed by singletons with HDP (HR 5.89, 95% CI 5.70-6.08) and then twins without HDP (HR 1.95, 95% CI 1.75, 2.17).

CONCLUSIONS

Compared with singletons without HDP, twin pregnancies, even in the absence of HDP, are associated with increased risks for CVD complications in the first year post-partum. These findings highlight the increased strain twin pregnancies place on the maternal cardiovascular system. These findings advocate the need for appropriate pre-conception counselling for those with cardiovascular risk factors undergoing infertility treatment, which increase the risks of multi-foetal gestation, and increased post-partum surveillance in twin pregnancies.

Intact NOX2 in T Cells Mediates Pregnancy-Induced Renal Damage in Dahl SS Rats

BACKGROUND

Hypertensive disorders of pregnancy are associated with increased risk for cardiovascular disease, renal disease, and mortality. While the exact mechanisms remain unclear, T cells and reactive oxygen species have been implicated in its pathogenesis. We utilized Dahl salt-sensitive (SS), SSCD247-/- (Dahl SS CD247 knockout rat; lacking T cells), and SSp67phox-/- (Dahl SS p67phox [NOX2 (NADPH [nitcotinamide adenine dinucleotide phosphate] oxidase 2)] knockout rat; lacking NOX2) rats to investigate these mechanisms in primigravida and multigravida states.

METHODS

We assessed blood pressure and renal damage phenotypes in SS, SSCD247-/-, and SSp67phox-/- rats during primigravida and multigravida states. To investigate the contribution of NOX2 in T cells, we performed adoptive transfers of splenocytes or cluster of differentiation (CD)4+ T cells from either SS or SSp67phox-/- donors into SSCD247-/- recipients to determine pregnancy-specific alterations in phenotype.

RESULTS

Multigravida SS rats developed significant pregnancy-induced renal damage and renal functional impairment associated with elevated maternal mortality rates, whereas deletion of T cells or NOX2 garnered protection. During primigravida states, this attenuation in renal damage was observed, with the greatest protection in the SSp67phox-/- rat. To demonstrate that NOX2 in T cells contributes to adverse pregnancy phenotypes, adoptive transfer of SS splenocytes into SSCD247-/- rats resulted in significant pregnancy-induced renal damage, whereas transfer of SSp67phox-/- splenocytes garnered protection. Specifically, the transfer of SS CD4+ T cells resulted in pregnancy-induced proteinuria and increases in uterine artery resistance index, an effect not seen with the transfer of SSp67phox-/- CD4+ T cells.

CONCLUSIONS

T cells and NOX2-derived reactive oxygen species, thus, contribute to end-organ damage in both primigravida and multigravida pregnancies in the SS rat leading to increases in maternal mortality.