Recurrent Placenta-mediated Complications Research Articles

Low-Molecular-Weight Heparin and Recurrent Placenta-Mediated Pregnancy Complications: A Meta-analysis of Individual Patient Data From Randomised Controlled Trials

Placenta-mediated pregnancy complications include pre-eclampsia, birth of a small-for-gestational-age neonate, placental abruption, or late pregnancy loss and lead to maternal and fetal or neonatal morbidity and mortality. These complications have a high risk of recurring in subsequent pregnancies, and effective preventive measures are lacking. Findings from some randomized controlled trials suggest that low-molecular-weight heparin (LMWH) can be used to prevent recurrent placentamediated pregnancy complications, but these findings have not been universal. An individual patient data meta-analysis was done to evaluate the efficacy of LMWH to prevent recurrent placentamediated complications in subsequent pregnancies. The primary outcome was a composite of 4 pregnancy complications: early-onset or severe preeclampsia, birth of a small-for-gestational-age neonate (birth weight less than the fifth percentile), placental abruption, and late pregnancy loss. The data set included a total of 963 eligiblewomen from 8 randomized published trials. The primary outcome analysis showed that LMWH did not significantly reduce the risk of recurrent placenta-mediated pregnancy complications (LMWH 62/444 [14%] vs no LMWH 95/443 [22%]; absolute difference, 8% [95% confidence interval, 17.3-1.4; P = 0.09]; relative risk, 0.64 [95% confidence interval, 0.36-1.11; P = 0.11]). Significant heterogeneity was noted between single-center and multicenter trials for the primary composite outcomes and also in the subgroup analyses. Low-molecular-weight heparin was found to be beneficial in women with previous placental abruption in both single-center and multicenter trials but not in any other subgroups of previous complications. No serious adverse reaction to LMWHwas observed. Inclusion of individual patient data set enabled a robust exploration of clinical, methodological, and statistical heterogeneity. In conclusion, this individual patient data meta-analysis showed that LMWH did not significantly reduce the risk of recurrent placenta-mediated pregnancy complications in women with previous complications

Recurrent Placenta-Mediated Complications in Women With Three Consecutive Deliveries.

To estimate the risk of placenta-mediated complications in women in their third delivery according to their obstetric history in the first and second deliveries. A retrospective cohort study of all women with singleton pregnancies who delivered their first three consecutive deliveries in a single medical center over a 20-year period (1994-2013). The risk of placenta-mediated complications in the third delivery, that is, hypertensive disorders such as preeclampsia or gestational hypertension, placental abruption, and small for gestational age (SGA less than the 10th percentile), was assessed according to the presence or absence of complications in previous deliveries. Pregnancies complicated by multiple gestations or fetal anomalies were excluded. Of the 121,728 deliveries during the study period, 4,472 women (13,416 deliveries [11.0%]) met inclusion criteria. The rate of placenta-mediated complications in the third delivery was 5.9% (n=264). The most prevalent placenta-mediated complication was SGA. The risk of each placenta-mediated complication was greater the higher the incidence of placenta-mediated complications in prior pregnancies. In multivariate analysis, that risk was significantly associated with the number and order of complications in previous deliveries in a dose-dependent pattern: with no complications in either their first or second deliveries as a reference (n=3,650), the adjusted odds ratio (and 95% confidence intervals) was 4.35 (3.03-6.24) for complications in the first delivery but not the second delivery (n=532); 6.41 (3.95-10.38) for complications in the second delivery but not the first delivery (n=179); and 8.28 (4.72-14.58) for complications in both first and second deliveries (n=111), (P<.001). The number and order of previous placenta-mediated complications in the first two deliveries are major risk factors for recurrence in the third delivery. Previous SGA was the strongest risk factor for recurrence of SGA and other placenta-mediated complications.