Research Article

Twin Pregnancy in Brazil: A Profile Analysis Exploring Population Information from the National Birth E-Registry on Live Births

Table 4

Perinatal outcomes from twin pregnancies according to the presentation of the first twin, Brazil, SINASC 2011-2014.

Perinatal outcomesCephalic n (%)Non-cephalic n (%)Cramer V

Gestational age at birth 0.0384
 < 28 weeks2 662 (3.27)995 (4.07)
 28-31 weeks5 204 (6.39)1 947 (7.97)
 32-36 weeks35 383 (43.47)10 864 (44.48)
 ≥ 37 weeks38 141 (46.86)10 616 (43.47)
Onset of labor 0.0874
 Spontaneous24 470 (39.27)9 088 (45.21)
 Induced7 816 (12.54)1 310 (6.52)
 No labor30 021 (48.18)9 704 (48.27)
Type of birth 0.1233
 Elective cesarean26 359 (43.20)8 475 (47.47)
 Intrapartum cesarean21 265 (34.85)7 488 (41.94)
 Vaginal 1st/cesarean 2nd981 (1.61)226 (1.27)
 Vaginal 1st/vaginal 2nd12 413 (20.34)1 663 (9.32)
5 min Apgar 1st twin 0.0000
 < 72 282 (2.78)896 (3.64)
 ≥ 779 726 (97.22)23 714 (96.36)
5 min Apgar 2nd twin 0.0000
 < 71 454 (2.44)771 (3.35)
 ≥ 758 081 (97.56)22 268 (96.65)
5 min Apgar 3rd twin 0.0480
 < 737 (4.99)12 (2.96)
 ≥ 7704 (95.01)393 (97.04)
5 min Apgar 4th twin 0.1016
 < 73 (13.04)1 (6.67)
 ≥ 720 (86.96)14 (93.33)

Missing data: (a) 24 189. (b) 47 592. (c) 51 131. (d) 23 383. (e) 18 907. (f) 399. (g) 13.