Journal: PLOS Medicine
Article Title: Risk of placenta previa in assisted reproductive technology: A Nordic population study with sibling analyses
doi: 10.1371/journal.pmed.1004536
Figure Lengend Snippet: Fresh-CT, fresh cleavage stage embryo transfer; NC, natural conception; fresh-BT, fresh blastocyst transfer; frozen-CT, frozen cleavage stage embryo transfer; frozen-BT, frozen blastocyst transfer. Adjusted for year of delivery (categorical: 1988–1996, 1997–2001, 2002–2006, 2007–2011, 2012–2015), maternal age (categorical: 20–24, 25–29, 30–34, 35–39, 40–45), parity (categorical: 0, 1, 2, 3), and country (only included in analyses at the population level because it is constant within mothers). Analyses in “Smoking” are additionally adjusted for smoking status in the subpopulation where this information was available. In “C-section” the outcome of placenta previa is restricted to pregnancies delivered by cesarean section, whereas “Full siblings,” “First two,” “<3 years,” “SET,” “IVF,” and “Singletons” refer to restriction of analyses to full siblings (i.e., same mother and father), each mothers’ first 2 consecutive deliveries, only consecutive deliveries less than 3 years apart, single embryo transfer (using all deliveries after NC as reference), in vitro fertilization (using all deliveries after NC as reference), and singleton pregnancies, respectively.
Article Snippet: We estimated adjusted odds ratios (aORs) for placenta previa at the population level and within mothers using multilevel logistic regression with deliveries nested within mothers (using the “xtlogit” command in Stata with maternal identity codes specified as clusters).
Techniques: In Vitro