| Objective With the development of assisted reproductive technology, the proportion of pregnant women with twin pregnancy has increased. Twin pregnancy is a high-risk pregnancy, and preterm labour is the most common complication of twin pregnancy, which is also the main cause of neonatal morbidity and mortality. The incidence of preterm labour in twin pregnancy is almost 50%. Currently, the application of tocolytic agents is the primary method for preventing preterm labour; it provides ample time for transportation and the opportunity to apply corticosteroids to pregnant women Currently, the Royal College of Obstetrics and Gynaecology(RCOG) recommends atosiban as the primary drug for anti-preterm labour. During the treatment of preterm labour, tocolytic agents and other miscarriage prevention drugs showed a high risk for pregnant women with twin pregnancy, which may cause pulmonary edema and heart failure.In this study, we treated the late abortion and preterm labour of twin pregnancy with atosiban to investigate the treatment efficacy and safety of atosiban in the late abortion and preterm labour of twin pregnancy.Materials and Methods 1 Study population Hospitalized pregnant women with twin pregnancy in 24-33 weeks of gestation who showed signs of late abortion and preterm labour from June 2011 to June 2015 were selected as the research subjects in this study. The inclusion criteria were as follows:(1) cases in which women experienced regular contractions with durations ≥30 s and frequencies ≥4 times/30 min and(2) cases in which women showed cervical canal regression ≥50%. The exclusion criteria were as follows: premature rupture of membranes, cervix ≥3 cm, vaginal bleeding, preeclampsia, gestational hypertension, severe maternal disease, foetal growth restriction, foetus with chromosomal disorders, insufficient amount of amniotic fluid, and chorioamnionitis. A total of 60 cases were randomly divided into two groups: the first group contained 30 cases of a short course of treatment(18 hours), and the second group contained 30 cases of a long course of treatment(45 hours). All groups included pregnant women who showed no contraindication for a continuous pregnancy and the application of a tocolytic agent. This study was approved by the ethics committee of the Third Affiliated Hospital of Zhengzhou University, and all patients provided informed consent for participation. 2 Transvaginal ultrasound measurement of cervical length(1)Transvaginal ultrasound was performed after emptying the bladder.(2) The probe was placed in the interior fornix of the vagina, and excessive force was avoided.(3) At the standard sagittal plane, the image was enlarged to a minimum of 75% of the full screen, and the straight distance from the inner cervix to the outer cervix was measured to obtain the shortest value of three successive measurements. 3 Atosiban regimen Atosiban is the product of Ferring(Sweden) Pharmaceuticals Ltd. The 19 hour-program(short course of treatment) was as follows: first, a dose of 6.75 mg was intravenously injected with a speed greater than 1 min; second, an atosiban injection of 20 ml(specification of 7.5 mg/ml) in 180 ml of 0.9% sodium chloride injection or 5% glucose injection was administered by intravenous infusion at the speed of 300 μg/ml for 3 h; and, last, the same injection was administered at the speed of 100 μg/min until the desired effect of inhibiting uterine contractions was achieved. The total time was approximately 19 h. The 44-hour program(long course of treatment) was as follows: first, a dose of 6.75 mg was intravenously injected with a speed greater than 1 min; second, an atosiban injection of 40 ml in 360 ml of 0.9% sodium chloride injection or 5% glucose injection was administered by intravenous infusion at a speed of 300 μg/ml for 3 h; and, last, the same injection was administered by 100 μg/min until the desired effect of inhibiting uterine contractions was achieved. The total time was approximately 44 h. Repeated treatment can be provided to pregnant women with recurrent symptoms of preterm labour after a successful inhibition of contractions. All pregnant women admitted to the hospital underwent a course of corticosteroid therapy. 4 Outcome measures(1) The treatment efficacy and safety of the extended gestational age for 48 h and 7 d between the short course of treatment group and the long course of treatment group were compared.(2) The efficacies in contraction suppression between the group with CL ≥20 mm and the group with CL <20 mm for either the long course of treatment program or the short course of treatment program were compared.(3) The condition during the delivery, the postnatal situation, and the neonatal morbidity and mortality were observed and analysed. 5 Criteria of efficacy and safety Effective tocolysis: after the treatment, contractions and cervical dilation gradually ceased with continuous pregnancy of more than 48 h. Ineffective tocolysis: after the treatment, contractions were not weakened and delivery occurred within 48 h. Safety: any possible adverse events were included, such as nausea, vomiting, tremors, tachycardia, hypotension, headache, pulmonary edema, haemorrhage, and deep venous thrombosis. 6 Statistical analysis The data were analysed using SPSS 17.0 software. The counting data were represented as percentages. The χ2 test or the Fisher’s exact test was performed. The measurement data were represented as x±s, and the comparison between the groups was performed using the t test. Difference with P<0.05 were considered to be statistically significant.Results 1 Efficacy of the drug treatment Among the 60 cases of pregnant women with twin pregnancy who received the atosiban treatment, 85.0%(51/60) of the women did not deliver within 48 hours and 63.3%(38/60) of the women did not deliver within 7 days. The gestation was prolonged for a minimum of 15 hours and a maximum of 74 days. The comparison of the efficacy for the short course of treatment and the long course of treatment is shown in Table 2. The results of the χ2 test suggested that the rates of the 48 h and 7 d effective contraction suppression in the long course of treatment group were significantly superior to the same rates in the short course of treatment group, and the differences were statistically significant(P<0.05). 2 Safety of the treatment in the short and long course of the treatment groups In the long course of treatment group, one case of headache and nausea was reported and one case of palpitation and chest tightness was reported, which did not affect the treatment. In the short course of treatment group, one case of nausea was reported and one case of pruritus was reported, which did not affect the treatment. The incidence of adverse events for the two groups showed no statistically significant differences(6.7% vs. 6.7%, P>0.05).In the 30 cases of pregnant women who received the long treatment, 16 cases showed CL ≥20 mm and 14 cases showed CL <20 mm. The results of the comparison in the efficacy of atosiban treatment between the two cases are listed in Table 3. The rates of the 48 h and 7 d effective tocolysis with two different cervical lengths showed no statistically significant differences. In the 30 cases of pregnant women who received the short course of treatment, 17 cases showed CL ≥20 mm and 13 cases showed CL <20 mm. The results of the comparison of the efficacy of the atosiban treatment between the two types of CL are listed in Table 4. The rates of the 48 h and 7 d effective tocolysis with CL ≥20 mm were significantly superior to the same rates with CL <20 mm, and the differences were statistically significant. 4 Pregnancy outcome The morbidity rates for the 101 survived neonates are listed in. 3 Efficacy of the treatment in the pregnant women with different cervical lengthsConclusions 1.Atosiban can effectively extend the pregnancy time for twin pregnancy with late abortion and preterm labour. 2.The long course of the treatment program was more effective and performed better for the cases in which CL <20 mm. 3.The long course of treatment did not increase the adverse events for the mothers and infants. |
