Success rate in preterm uterine contraction inhibition with tocolytic agents in a tertiary care center

Figures & data

Table 1 Baseline characteristics of pregnant women

Characteristics	Mean ± SD or N (%)
Age, years	28.4±7.0
Prepregnancy BMI, kg/m^2	21.0±3.5
<18.5 (underweight)	23 (22.3)
≥30 (obesity)	4 (3.9)
Primiparity	66 (64.1)
Gestational age on admission, weeks	30.8±2.4
Number of antenatal care visit	7.0±2.7
History of pregnancy complications	80 (77.7)
Uterine contraction and cervical condition
Threatened preterm labor	80 (77.7)
Preterm labor	23 (22.3)

Abbreviations: BMI, body mass index; SD, standard deviation.

Table 2 Success rate of preterm uterine contraction inhibition

Group of studied women	Success rate (95% CI)
All uterine contraction inhibition	86.4 (78.3, 92.3)
Threatened preterm labor (n=80)	93.8 (88.3, 99.1)
Preterm labor (n=23)	60.9 (39.3, 82.4)
High risk of preterm delivery (n=80)	85.0 (77.0, 93.0)
Cervical dilatation, cm
1 (n=8)	75.0 (36.3, 100)
2–3 (n=11)	54.5 (36.3, 100)
≥4 (n=4)	50.0 (0, 100)
Type of tocolytics
CCB (n=28)	96.4 (89.1, 100)
Betamimetics (n=45)	86.7 (76.3, 96.9)
Combine CCB + betamimetics (n=30)	76.7 (60.6, 92.7)
Completed course of corticosteroids	85.4 (77.1, 91.6)
Delivery after 34 weeks gestational age	55.3 (45.6, 65.1)
Delivery after 37 weeks gestational age	38.8 (29.3, 48.4)

Abbreviations: CCB, calcium channel blocker; CI, confidence interval.

Table 3 Neonatal outcomes

Neonatal outcomes	N (%)
Birth weight <2,500 g	51 (49.5)
Route of delivery
Spontaneous vaginal delivery	39 (37.9)
Cesarean section	60 (58.3)
Vacuum and extraction	2 (1.9)
Breech assisting	2 (1.9)
APGAR score
At the 5th minute <6	9 (8.7)
At the 5th minute <4	4 (3.9)

Abbreviation: APGAR, appearance, pulse, grimace, activity, respiration.

Table 4 Risk factors of inhibition failure

Risk factors	Inhibition failure (N=14)	Inhibition success (N=89)	Univariate P-value	Adjusted OR (95% CI)
Preterm labor*	9	14	<0.001	7.22 (1.99, 26.20)
Intolerable side effects	4	9	0.065	2.43 (0.52, 11.33)
PPROM	5	13	0.063	1.99 (0.48, 8.33)
Maternal BMI <18.5 kg/m^2	6	17	0.056	2.63 (0.69, 10.09)

Note:

* Regular uterine contractions accompanied by a change in cervical dilatation, effacement, or both.

Abbreviations: BMI, body mass index; CI, confidence interval; OR, odds ratio; PPROM, preterm pre-labor rupture membranes.