Figure 8. Effects of placental sFlt1 knockdown with or without endometrial VEGF overexpression. (A-L) Placental sFlt1 knockdown. Upon placentaspecific sFLT1 shRNA expression, widespread hemorrhaging in the fetus (B) and at the placental-decidual junction (D) was observed on GD18 compared with controls (A and C). Histological examination of sFLT1 shRNA-expressing placentas revealed extraordinary dilation of some maternal blood sinuses (arrowheads) in the labyrinth (E and F) and fibrin deposition (arrow) in these spaces (G and H). (I and J) MSB staining revealed extravasated fibrin (arrow) in adjacent areas. Placental sFlt1 knockdown did not affect implantation rate (K), whereas the fetal resorption rate significantly increased (L). (M-V) Placental sFlt1 knockdown enhanced the deleterious effects in Endo-VEGF animals. Pregnancies surviving to GD16 exhibited (M) excessive vaginal bleeding and (N-P) termination of pregnancy or resorption (arrows denote resorption sites) as well as (Q) widespread and extensive hemorrhaging in fetuses and placentas (arrowheads) and in deciduas at the maternal-fetal junction (asterisk). Histological examination (R-T) revealed widespread dilation and congestion of maternal blood sinuses (arrowheads) in the labyrinth, venous sinuses, and veins at maternal-fetal junctions, and MSB staining (U and V) demonstrated extensive fibrin extravasation (arrows) in the labyrinth and at the maternal-fetal junction. Results are mean ± SD. *P < 0.05 (n = 15). Scale bars: 2 mm (A-D); 500 μm (E, F, and R); 50 μm (G-J); 100 μm (S-V).

No abstract

Identification of maternal environmental factors influencing preterm birth risks is important to understand the reasons for the increase in prematurity since 1990. Here, we utilized a health survey, the US National Health and Nutrition Examination Survey (NHANES) to search for personal environmental factors associated with preterm birth. 201 urine and blood markers of environmental factors, such as allergens, pollutants, and nutrients were assayed in mothers (range of N: 49 to 724) who answered questions about any children born preterm (delivery <37 weeks). We screened each of the 201 factors for association with any child born preterm adjusting by age, race/ethnicity, education, and household income. We attempted to verify the top finding, urinary bisphenol A, in an independent study of pregnant women attending Lucile Packard Children’s Hospital. We conclude that the association between maternal urinary levels of bisphenol A and preterm birth should be evaluated in a larger epidemiological investigation.

Our data suggest, for the first time, an interaction between VEGF and Tie2 in uterine endothelial cells and a potential mechanism for the decrease in circulating sTie2 levels in preeclampsia, likely through inhibition of VEGF signaling. Further studies on VEGF-Tie2 interactions during pregnancy should provide new insights into the mechanisms underlying the failure of vascular remodeling in preeclampsia and other pregnancy complications.

Stercoral perforation of the colon is rare in pregnancy. Prompt surgical treatment is necessary. Surgical exploration may be warranted in the pregnant patient with unexplained abdominal pain.