Long interpregnancy interval and mode of delivery.

PURPOSE: WHO sets 24 months as the ideal minimum interpregnancy interval (IPI) to minimize maternal and perinatal adverse outcomes. Some studies suggest that an interval longer than 59 months may affect these outcomes, but little is known about its influence on labor. The primary objective of this study was to compare the cesarean delivery rate between primiparous women with a long IPI and, on the one hand, primiparous women with an ideal minimum IPI of 18-24 months and, on the other hand, with nulliparous women. METHODS: This retrospective cohort study of 17 years included nulliparas and primiparas who gave birth to live singleton fetuses in cephalic presentation after 22 weeks of gestation. Women with an IPI < 18 months or from 24 to 59 months were excluded, as were women with planned cesarean. We analyzed three groups: primiparous women with a long IPI defined as > 59 months, primiparous women with an ideal minimum IPI (18-24 months), and nulliparous women. RESULTS: The study included 18,503 women: 1342 women in the "long IPI" group, 1388 in the "ideal minimum IPI" group, and 15,773 in the nulliparous women group. The cesarean delivery rate was significantly higher in the long compared to the ideal minimum IPI group [12.2% vs. 6.3%, respectively; aOR = 2.2 (95% CI 1.6-3.1)], but both groups had similar durations of labor, regardless of mode of delivery. Women in the long IPI group had significantly lower cesarean rates than nulliparous women [12.2% and 14.3%, respectively; aOR = 0.5 (95% CI 0.4-0.7)], and the nulliparous women had a significantly longer mean duration of labor. CONCLUSIONS: Primiparas with a long IPI, compared with ideal minimal IPI have a higher risk of cesarean delivery during labor. Compared with nulliparous women, primiparous women with a long IPI had a lower cesarean rate.

Investigation of oxidative stress enzymes and histological alterations in tilapia exposed to chlorpyrifos.

Chlorpyrifos (ChF) is an organophosphate pesticide that is widely used in agricultural fields and indoor for controlling pests. Aquatic ecosystems are the recipients of various pesticide residues due to leaching spray drift and agricultural runoff and pose toxicity for aquatic organisms. Therefore, the current study was designed to investigate the oxidative stress enzymes and histological alterations in the vital organs of tilapia due to ChF exposure. LC50 (24 h) was calculated as 52.78 µg/l by exposing tilapia with different acute concentrations of ChF. For assessment of sub-lethal toxicity of ChF, the fish were divided into four groups (ChF1, ChF2, ChF3, and control group). ChF1 group was treated with 1/15th of LC50, whereas ChF2 and ChF3 groups were treated with 1/10th and 1/5th of LC50, respectively for 14 days. After that, ChF induced changes in oxidative stress enzymes and histological alterations were evaluated. It was found that the level of glutathione S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) increased significantly in the liver of ChF-treated tilapia. Histological study of liver tissues showed an increased number of Kupffer cells, hydropic degeneration, necrosis, and hemorrhage. In the spleen of treated fish, increased melanomacrophage centers, necrosis, and congestion were detected. Disorganized muscle fibers, cardiac muscle fiber degeneration, and coagulative necrosis were observed in the heart of ChF-treated fish. It is concluded that sub-lethal concentrations of ChF can induce oxidative stress and histological alterations in the tissues of tilapia.