[Variation of prevalence of macrosomia and cesarean section and its influencing factors].

To investigate the varaiation of the incidence of macrosomia and its influencing factors.A population-based study of 25 944 pregnant women, who delivered in Peking University First Hospital in term birth, with singleton, between Jan. 1, 2006 and Dec. 31, 2013 and accepted the gestational diabetes mellitus (GDM) screening and diagnosis, was performed. The women are grouped according to the different clinical interventions at different period. Women delivered between Jan.1, 2006 and Dec. 31, 2006 was defined as Group 2006, and they were diagnosed with glucose metabolism disorder [gestational impaired glucose tolerance (GIGT) and GDM] and intervened only when meeting National diabetes data group (NDDG) criteria. Women delivered between Jan. 1, 2007 and Apr. 30, 2011 were defined as Group post 2007, and NDDG criteria was also applied in this period. Women delivered between May. 1, 2011 and Dec. 31, 2013 were defined as Group post 2011, and Ministry of Health (MOH) of China was used for GDM diagnosis in this group. All pregnant women in Group post 2007 accepted the preliminary pregnancy nutrition advice and weight management. All participants met MOH criteria were diagnosed as glucose metabolism disorder in this study, in which women diagnosed and intervened in pregnancy were defined as Group diagnosis and those not being identified during pregnancy were defined as Group missed diagnosis. It was analyzed retrospectively for the incidence of macrosomia and the influencing factor.(1) The prevalence of macrosomia and cesarean section was decreased every year from Jan. 2006 to Dec. 2013. The incidence of macrosomia was 9.14% in 2006, reduced to 8.02% in 2007-2011 and 6.79% in 2011-2013. The incidence of cesarean section was 55.22%, reduced to 51.04% in 2007-2011 and 44.15% in 2011-2013. However, there was not remarkable change in the prevalence of small for gestational age (P > 0.05). (2) Compared with Group 2006, the incidence of cesarean section was lower in Group post 2007 [51.04% (6 504/12 744) vs 55.22% (1 371/2 483)], and the difference is significantly (P < 0.05). Meanwhile, the incidence of cesarean section (44.15%, 4 732/10 717) and macrosomia (6.79%,728/10 717) in Group post 2011 was lower significantly than Group 2006 and Group post 2007 (P < 0.05). (3) The incidence of macrosomia was 7.41% (1 129/15 227) and 6.61% (1 006/15 227) respectively in Group diagnosis and Group missed diagnosis before May 2011, combined 14.02% (2 135/15 227) in total. It was increased significantly in the incidence of GDM 21.41% (2 294/10 717) after May 2011 compared with that before (P < 0.05). The incidence of macrosomia was decreased significantly using MOH criteria in GDM women since 2011. It was the downtrend in the incidence of macrosomia since 2007 in non GDM women. However, there was no difference in SGA in different period. (4) In glucose metabolism disorder women, compared with Group 2006 and Group post 2007, the incidence of macrosomia and cesarean section was lower in Group post 2011, and the difference is significantly (P < 0.05). However, there was no significant difference in the incidence of macrosomia and cesarean section between Group 2006 and Group post 2007, and there was no difference in SGA in the 3 groups ( P > 0.05). In non GDM women, the incidence of macrosomia and cesarean section was lower in Group post 2011 than Group 2006 (P < 0.05); meanwhile, it was the downtrend in the incidence of macrosomia in Group post 2007 compared to Group 2006, and the difference of the incidence of cesarean section was significant (P < 0.05).The prevalence of macrosomia and cesarean section might be reduced by application of suitable criteria for diagnosis of GDM and education on nutrition during pregnancy.