BACKGROUND Inositol is an essential nutrient for cell growth, survival and embryonic development. Myo-inositol is the predominant form in natural. To investigate the correlation between inositol metabolism and embryonic development, we assessed the metabolic characteristics of myo-inositol, phosphatidylinositol 4,5-bisphosphate (PI(4,5)P₂) and phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P₃) of pregnant women in the North China (Yangquan and Weihai) and South China (Nanchang and Haikou) China. MATERIAL AND METHODS All data were collected by face-to-face interview during pregnant women health visits using a questionnaire. Plasma levels of myo-inositol, PI(4,5)P₂ and PI(3,4,5)P₃ from 89 randomly collected pregnant women were detected by gas chromatography-mass spectrometry and enzyme linked immunosorbent assay. RESULTS A total of 400 pregnant women were included in this survey. The plasma levels of myo-inositol and PI(4,5)P₂ in the North China group of pregnant women were significantly higher than that in the South China group (P<0.01). The birth weight of fetuses in the North China group was heavier than that in the South China group (P<0.01). The birth length of fetuses in Yangquan was the longest among the 4 cities (P<0.01). The incidence rate of birth defects was 3.05% in the North China group, and 0.0% in the South China group. In bivariate linear correlation analysis, the body weight correlated with myo-inositol (r=0.5044, P<0.0001), PI(4,5)P₂ (r=0.5950, P<0.0001) and PI(3,4,5)P₃ (r=0.4710, P<0.0001), the body length was correlated with PI(4,5)P₂ (r=0.3114, P=0.0035) and PI(3,4,5)P₃ (r=0.2638, P<0.0130). CONCLUSIONS The plasma levels of myo-inositol and PI(4,5)P₂ in pregnant women had significant difference between the North and the South of China, which might be correlated with fetal development and birth defects.