266. Demographic characteristics and angiogenic profile in relation to fetal sex

Introduction Fetal sex has been shown to alter maternal milieu, with patients carrying a male fetus having an altered inflammatory response in pregnancy. Angiogenic biomarkers sFlt1 and PlGF are associated with preeclampsia, however the difference in angiogenic profile with respect to the fetal sex is not previously analyzed. Methods In this retrospective cohort analysis, women with preeclampsia and normal pregnancy were enrolled upon admission to labor and delivery. Blood samples were collected and were assessed for angiogenic factors using an automated platform. Clinical and demographic information was abstracted from medical records and presented as median (interquartile range) or n (%). Results A total of 299 normotensive and 130 women with preeclampsia were enrolled. Equal number of patients had male fetuses among preeclampsia and normotensive parturients (55.9% and 50.2% respectively). Among both normotensive and women with preeclampsia, no difference was observed in demographic characteristics between male and female fetuses, including age (normotensive), body mass index, smoking or racial status, blood pressure, gestation age at delivery or birthweight (all p u003e 0.10). Normotensive mothers carrying a male fetus had significantly high sFlt1 (3168 [IQR: 2160–4945] vs 2678 [IQR: 1752–4271]; p = 0.01), lower PlGF (175 [IQR: 97–367] vs 215 [IQR: 124–426]; p = 0.09), and higher sFlt/PlGF ratios (18 [IQR: 7–44] vs 12 [IQR: 5–30]; p = 0.01). This difference between fetal sexes was not observed in the angiogenic profile of patients with preeclampsia; however, we did observe a higher maternal age (27 vs 24 years, p = 0.03) and rates of cesarean section, among patients with male fetuses in this cohort (54.7%vs 37.3%; p = 0.04). Conclusion Our study demonstrates that normotensive women carrying a male fetus have significantly worse angiogenic profile as compared to those carrying a female fetus. No such relationship exists for preeclamptic pregnancies. Further studies are needed to elucidate this mechanism.