. Author manuscript; available in PMC: 2017 Oct 3.

Published in final edited form as: J Matern Fetal Neonatal Med. 2015 Dec 7;29(15):2414–2422. doi: 10.3109/14767058.2015.1094049

Table 1.

Clinical characteristics and pregnancy outcome of the study population

Characteristics	Spontaneous early preterm delivery < 30 weeks (n=64)	Term delivery (n=128)	P-value
Mean maternal age, years (±SD)	34.9 ± 4.5	35.0 ± 4.0	NS
Nulliparity	15 (23.4%)	30 (23.4%)	NS
Previous spontaneous preterm delivery	6 (9.4%)	5 (3.9%)	NS
Median gestational age at amniocentesis, weeks (range)	17.7 (15.6–22.3)	17.6 (15.4–23.0)	NS
Median gestational age at delivery, weeks (range)	23.0 (16.6–29.7)	39.0 (37.0–41.4)	<0.001
Positive MMP-8 rapid kit result	42.2% (27/64)	0.0% (0/128)	<0.001

SD = Standard deviation; NS = Not significant; MMP = Matrix metalloproteinase

Data are presented as median (range) or n (%).