Interpregnancy intervals and adverse birth outcomes in high-income countries: an international cohort study

Published: July 19, 2021Background: Most evidence for interpregnancy interval (IPI) and adverse birth outcomes come from studies that are prone to incomplete control for confounders that vary between women. Comparing pregnancies to the same women can address this issue.Methods: We conducted an international longitudinal cohort study of 5,521,211 births to 3,849,193 women from Australia (1980–2016), Finland (1987–2017), Norway (1980–2016) and the United States (California) (1991–2012). IPI was calculated based on the time difference between two dates—the date of birth of the first pregnancy and the date of conception of the next (index) pregnancy. We estimated associations between IPI and preterm birth (PTB), spontaneous PTB, and small-for-gestational age births (SGA) using logistic regression (between-women analyses). We also used conditional logistic regression comparing IPIs and birth outcomes in the same women (within-women analyses). Random effects meta-analysis was used to calculate pooled adjusted odds ratios (aOR). Results: Compared to an IPI of 18–23 months, there was insufficient evidence for an association between IPI 24 month IPIs. Conclusions: We found consistently elevated odds of adverse birth outcomes following long IPIs. IPI shorter than 6 months were associated with elevated risk of spontaneous PTB, but there was insufficient evidence for increased risk of other adverse birth outcomes. Current recommendations of waiting at least 24 months to conceive after a previous pregnancy, may be unnecessarily long in high-income countries.Gizachew A. Tessema, M. Luke Marinovich, Siri E. Håberg, Mika Gissler, Jonathan A. Mayo, Natasha Nassar ... et al

Experimental acrylonitrile butadiene styrene and polyamide evisceration implant: a rabbit clinical and histopathology study

ABSTRACT The purpose of this study was to evaluate acrylonitrile butadiene styrene (ABS) and polyamide implants in rabbits submitted to evisceration at the macroscopic and microstructure level and to assess clinical response and histopathological changes as well. For the experimental study implants of 12mm diameter were prepared by rapid prototyping, weighed and the outer and inner surfaces evaluated macroscopically and by electron microscopy. In addition, a compression test was performed and ultrastructural damage was then determined. After evisceration of the left eyeball, nine New Zealand rabbits received ABS implants and nine others received polyamide implants. The animals were assessed daily for 15 days after surgery and every seven days until the end of the study (90 days). Histopathological evaluation was performed at 15, 45 and 90 days after surgery. The ABS implants weighed approximately 0.44g, while the polyamide ones weighed 0.61g. Scanning electron microscopy demonstrated that the ABS implants had regular-sized, equidistant micropores, while the polyamide ones showed micropores of various sizes. The force required to fracture the ABS implant was 14.39 ±0.60 Mpa, while for the polyamide one, it was 16.80 ±1.05 Mpa. Fifteen days after surgery, we observed centripetal tissue infiltration and scarce inflammatory infiltrate. Implants may be used in the filling of anophthalmic cavities, because they are inert, biocompatible and allow tissue integration

MTDH Expression in Invasive Micropapillary Carcinoma of the Breast

OBJECTIVE To clarify the expression of MTDH in invasive micropapillary carcinoma of the breast (IMPC) and analyze the relationship between MTDH expression and clinicalpathologic parameters of the IMPC patietns.METHODS The expression of MTDH protein was analyzed using immunohistochemical staining in 86 cases with IMPC and another 86 cases with invasive ductal carcinoma not otherwise specified (IDC-NOS). The association between MTDH expression and clinicalpathologic parameters of the IMPC patients was analyzed.RESULTS Immunohistochemical analysis revealed the high expression of MTDH in 64 of the 86 (64/86, 74.4%) IMPC patients and in 45 of the 86 (45/86, 52.3%) IDC-NOS patients. Statistical analysis showed a statistically significant difference in MTDH expression between IMPC and IDC-NOS (P<0.05). In IMPC, the expression of MTDH was correlated with lymph nodes metastasis (P<0.05). The expression of MTDH was negative in normal breast tissue of IMPC and IDC-NOS patients.CONCLUSION High expression of MTDH is one of the molecular mechanisms, which facilitates lymph node metastasis of IMPC, therefore, the expression level of IMPC plays an important role in lymph node metastasis of IMPC