Effect of Placenta Previa on Preeclampsia

Abstract

BackgroundThe correlation between gestational hypertension-preeclampsia (GH-PE) and placenta previa (PP) is controversial. Specifically, it is unknown whether placenta previa has any effect on the various types of preeclampsia (PE), and the role PP with concurrent placenta accreta (PA) play in the occurrence of GH-PE are not well understood.ObjectiveThe aim of this study was to identify the effects of PP on GH, mild and severe preeclampsia (MPE and SPE), and early- and late-onset preeclampsia (EPE and LPE). Another aim of the study was to determine if concurrent PA impacts the relationship between PP and GH-PE.MethodsA retrospective single-center study of 1,058 patients having singleton pregnancies with PP was performed, and 2,116 pregnant women were randomly included as controls. These cases were collected from a tertiary hospital and met the inclusion criteria for the study. Clinical information, including PP and the gestational age at the onset of GH-PE were collected. Binary and multiple logistic regression analyses were conducted after the confounding variables were controlled to assess the effects of PP on different types of GH-PE.ResultsThere were 155 patients with GH-PE in the two groups. The incidences of GH-PE in the PP group and the control group were 2.5% (26/1058) and 6.1% (129/2116), respectively (P = 0.000). Binary and multiple regression analyses were conducted after controlling for confounding variables. Compared to the control group, in the PP group, the risk of GH-PE was reduced significantly by 78% (AOR: 0.216; 95% CI: 0.135–0.345); the risks of GH and PE were reduced by 55% (AOR: 0.451; 95% CI: 0.233–0.873) and 86% (AOR: 0.141; 95% CI: 0.073–0.271), respectively; the risks of MPE and SPE were reduced by 73% (AOR: 0.269; 95% CI: 0.087–0828) and 88% (AOR: 0.123; 95% CI: 0.055–0.279), respectively; and the risks of EPE and LPE were reduced by 95% (AOR: 0.047; 95% CI: 0.012–0.190) and 67% (AOR: 0.330; 95% CI: 0.153–0.715), respectively. The incidence of concurrent PA in women with PP was 5.86%; PP with PA did not significantly further reduce the incidence of GH-PE compared with PP without PA (1.64% vs. 2.51%, P>0.05). Binary logistic regression analyses were conducted after controlling for confounding variables, compared with the non-PP + GH-PE group, and the AOR of FGR in the non-PP + non-GH-PE group was 0.206 (0.124–0.342). Compared with the PP + GH-PE group, the AOR of FGR in the PP + non-GH-PE group was 0.430 (0.123–1.500).ConclusionPP is not only associated with a significant reduction in the incidence of GH-PE, but also is associated with a reduction in incidence of various types of PE. Concurrent PA and PP do not show association with a reduction in incidence of GH-PE.

Adverse Pregnancy Outcomes of Patients with History of First-Trimester Recurrent Spontaneous Abortion

“…But the relationship between gestational hypertension and placenta previa remains controversial. A meta-analysis by Ying et al [ 22 ] revealed that patients with gestational hypertension have a reduced risk of placenta previa. In this study, no significant difference of placenta previa occurrence was observed between the two groups.…”

Assessment of Fetal Myocardial Performance Index in Women with Placenta Previa

“…The supply of blood and oxygen is greater when the placenta is implanted in the lower uterine segment rather than in the upper segment. Thus, hypoxemia can be improved and vascular remodeling can occur more easily [ 34 , 35 ]. Complete placenta previa often occurs with concurrent placenta accrete, and trophoblasts implant more deeply [ 36 , 37 ], which can contribute to more blood flow to the intervillous space.…”

The association between placenta previa and the risk of preeclampsia: a meta-analysis

“…Evidences show that in pregnant women with placenta previa, women with pre-eclampsia had no higher incidence of fetal growth restriction than women without pre-eclampsia. These findings may be due to increased placenta blood supply in pregnant women with placenta previa (22).…”

“…Three studies were case-control (8,17,18), five studies were cohort (13,(19)(20)(21)(22), and one study was cross-sectional (23). The total sample size in the present meta-analysis was 752,243 participants.…”