Table 2 PTBs rate from 2005 to 2011 in Shenzhen
Items | Births | Proportion (%) | PTBs | Occurrence (%) |
|---|---|---|---|---|
All | 1,040,638 | 100 | 58,411 | 5.61 |
Year of births | ||||
 2005 | 94,335 | 9.07 | 5281 | 5.60 |
 2006 | 115,428 | 11.09 | 6379 | 5.53 |
 2007 | 146,934 | 14.12 | 7856 | 5.35 |
 2008 | 163,138 | 15.68 | 8995 | 5.51 |
 2009 | 158,953 | 15.27 | 8732 | 5.49 |
 2010 | 174,515 | 16.77 | 10,071 | 5.77 |
 2011 | 187,335 | 18.00 | 11,097 | 5.92 |
Maternal age | ||||
 Maternal age 15 ~ 19 group | 28,491 | 2.74 | 2135 | 7.49 |
 Maternal age 20 ~ 34 group | 913,845 | 87.82 | 48,409 | 5.30 |
 Maternal age 35 ~ 49 group | 80,976 | 7.78 | 6326 | 7.81 |
 Other (including missing or implausible) | 17,326 | 1.66 | 1541 | 8.89 |
Sex of fetus | ||||
 Male | 564,967 | 54.29 | 33,358 | 5.90 |
 Female | 475,535 | 45.70 | 25,038 | 5.27 |
 Uncertain | 136 | 0.01 | 15 | 11.03 |
Delivery mode | ||||
 Vaginal delivery | 643,955 | 61.88 | 33,105 | 5.14 |
 Cesarean section | 396,683 | 38.12 | 25,306 | 6.38 |