Skip to main content
. Author manuscript; available in PMC: 2018 Jul 1.
Published in final edited form as: Am J Obstet Gynecol. 2017 Mar 9;217(1):80.e1–80.e8. doi: 10.1016/j.ajog.2017.03.002

Table 2.

Pregnancy, neonatal, and infant outcomes among twins by maternal age group

Maternal age range, years 15–17 18–24 25–29 30–34 35–39 ≥40
Preterm birth, % (n)
 <34 weeks 32.7 (3,208) 24.6 (45,432) 20.5 (48,896) 18.7 (51,515) 18.4 (29,989) 20.5 (11,271)
 <37 weeks 67.7 (6,641) 61.6 (113,942) 58.9 (143,456) 56.6 (156,027) 56.1 (91,565) 58.1 (31,968)
Fetal deaths, rate (n)* 39.9 (408) 24.2 (4,597) 17.8 (4,406) 16.4 (4,591) 17.2 (2,859) 15.8 (885)
Neonatal death <28 days, rate (n)# 10.0 (98) 7.3 (1,352) 5.5 (1,342) 4.3 (1,195) 4.6 (751) 4.3 (237)
*

Fetal death rate calculated per 1,000 births (live births and fetal deaths).

#

Neonatal death rate <28 days calculated per 1,000 live births. All outcomes in this table were calculated using a full population of US natality data (2003 revised and unrevised birth certificate).