Evidence-based labour ward guidelines for the diagnosis, management and treatment of spontaneous preterm labour

The effectiveness of nifedipine/indomethacin combination therapy and nifedipine monotherapy for postponing preterm birth (25-34 weeks of gestation) in Sudanese women: a randomized clinical trial study protocol

BACKGROUND

Preterm birth is the most common cause of neonatal morbidity and mortality. Tocolytics are considered a standard treatment for women with threatened preterm delivery to allow time for maternal steroid administration and transfer to referral centers with neonatal intensive care units. However, there is controversy about the best tocolytic therapy to be considered as the first choice. The aim of this study is to compare the tocolytic effectiveness and tolerability of combination therapy with nifedipine and indomethacin versus nifedipine monotherapy among Sudanese women with preterm labor (PTL) as well as to compare the possible neonatal outcomes associated with each drug.

METHODS/DESIGN

This is a randomized controlled clinical trial to be conducted in the Medani Maternity Hospital, Sudan. Women aged 18-40 years that are diagnosed with preterm labor and have a gestational age between 25 and 34 weeks will be eligible to participate in this trial. The diagnosis of threatened PTL is defined as persistent uterine contractions "(four contractions every 20 min or eight contractions every 60 min)" with cervical changes "(cervical effacement ≤80% or cervical dilatation >two cm)". Patients will be eligible regardless of the presentation of the fetus. It will be randomly decided whether participants receive nifedipine/indomethacin combination therapy or nifedipine monotherapy. The primary outcome is the number of women who do not deliver and do not need alternative tocolytic drug (terbutaline). The secondary outcome is an estimated association with neonatal morbidity and mortality. The sample size will be 117 subjects in each arm of the study, according to a type I error of 0.05 and a study power of 80%.

DISCUSSION

We expect higher effectiveness of the combination indomethacin/nifedipine tocolytic therapy compared with nifedipine monotherapy. We plan to suggest this combination therapy as the best option for postponing PTL.

TRIAL REGISTRATION

Clinical trial registration: PACTR202004681537890 , date of registration: March 8, 2020.

Maternal and fetal parameters in pregnant woman undergoing tocolysis with nifedipine

Abstract Objectives: to evaluate the effects of nifedipine with tocolysis under maternal and fetal parameters. Methods: a cohort study with 40 pregnant women admitted at a high-risk pregnancy ward to inhibit premature labor between September/2010 to May/2012. Nifedipine was used as a 20mg sublingual attack dose and maintained 20mg every six and eight hours orally. The variables of the analysis were fetal heart rate (FHR), maternal heart rate (MHR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), and amniotic fluid index (AFI). All the variables were evaluated prior to administrating nifedipine and approximately after 6 hours and every 24 hours, until hospital discharge. Results: there were no modification of the FHR (p=0.48) and the SBP (p=0.29). The MHR increased after 24 hours, but with no statistical difference (p=0.08), returning to similar levels as at admission within 48 hours. The DBP decreased at 6 (p=0.04) to 72 hours, being stable afterwards. The AFI decreased significantly at 24, 48 and 72 hours. Conclusions: the use of high doses of nifedipine with tocolysis causes a decrease of the maternal’s diastolic blood pressure and consequently decreases the amniotic fluid index, but probably without any clinical repercussions.

Effectiveness of an oral versus sublingual loading dose of nifedipine for tocolysis

OBJECTIVE

To determine the effectiveness of an oral versus sublingual loading dose of nifedipine for tocolysis.

METHODS

An open, randomized clinical trial conducted between March 1, 2013, and April 31, 2014. Participants were pregnant women with a diagnosis of premature labor, single live fetus, topical pregnancy, gestational age 24-36 weeks, normal fetal vitality, cervical dilatation less than or equal to 4 cm, cervical effacement less than or equal to 80%, and intact amniotic membranes. They were randomized into two groups, oral and sublingual nifedipine, 20 mg loading dose, repeated every 30 minutes (maximum dose of 60 mg). The primary endpoint was the time until tocolysis and the secondary endpoints were the effectiveness of tocolysis within 90 minutes, 12 hours, and 48 hours; premature delivery within 48 hours; and maternal hemodynamic parameters and side effects.

RESULTS

There were 80 patients randomized to oral (n=40) and sublingual (n=40) nifedipine. The time required for tocolysis was significantly less with sublingual nifedipine (160 minutes vs 340 minutes; P=0.0003). Sublingual nifedipine was also more successful than oral nifedipine at inhibiting premature labor within 90 minutes (n=8 [20.0%] vs n=1 [2.5%], P=0.014). There was no statistically significant difference between the groups for the other secondary endpoints.

CONCLUSION

Compared with oral administration, a sublingual loading dose of nifedipine resulted in faster tocolysis in patients with premature labor. Brazilian Clinical Trials Registry (ReBEC): U1111-11566186.

Differences between evidence-based recommendations and actual clinical practice regarding tocolysis: a prospective multicenter registry study

BACKGROUND

International guidelines recommend that tocolytic therapy be restricted to a single 48-h application. However, multiple cycles of tocolytic therapy and maintenance therapy that exceeds 48 h appear to play a role in daily clinical practice. We aimed to evaluate current trends in clinical practice with respect to treatment with tocolytic agents and to identify differences between evidence-based recommendations and daily clinical practice in Austria.

METHODS

A prospective multicenter registry study was conducted from October 2013 through April 2015 in ten obstetrical departments in Austria. Women ≥18 years of age who received tocolytic therapy following a diagnosis of threatened preterm birth were included, and details were obtained regarding clinical characteristics, tocolytic therapy, and pregnancy outcome.

RESULTS

A total of 309 women were included. We observed a median of 2 cycles of tocolytic therapy per patient (IQR 1-3) with a median duration of 2 days per cycle (IQR 2-5). Repeat tocolysis was administered in 41.7% of women, resulting in up to six tocolysis cycles; moreover, 40.8% of the first tocolysis cycles were maintenance tocolysis (i.e., longer than 48 h). Only 25.6% of women received one single 48-h tocolysis cycle in which they received antenatal corticosteroids for fetal lung maturation in accordance evidence-based recommendations.

CONCLUSIONS

Here, we report a clear disparity between evidence-based recommendations and daily practice with respect to tocolysis. We believe that the general practice of prescribing tocolytic therapy must be revisited. Furthermore, our findings highlight the need for contemporary studies designed to investigate the effectiveness of performing maintenance and/or repetitive tocolysis treatment.

Características maternas em gestações com risco de prematuridade tardia

OBJETIVOS: avaliar as características maternas na prematuridade tardia. MÉTODOS: foi realizado um estudo do tipo corte transversal, com análise secundária das gestantes incluídas em um ensaio clínico randomizado realizado no Nordeste do Brasil, no período de 2008 a 2010, entre 34 e 36 semanas. Analisadas as variáveis maternas: idade, paridade, idade gestacional, antecedentes de prematuridade e condições clínicas associadas. A análise estatística foi realizada no programa Epi-Info 3.5.3. Foram construídas tabelas de distribuição de frequência para as variáveis categóricas e calculadas medidas de tendência central e de dispersão para as numéricas. Para determinação da associação entre a frequência das morbidades por estratos de idade gestacional, utilizou-se o teste qui-quadrado de associação. Considerou-se o nível de significância de 5%. RESULTADOS: foram analisadas 273 mulheres no IMIP com risco iminente de prematuridade tardia. A idade média foi 23,1 anos, 28,6% eram adolescentes e 53,8% primíparas. A idade gestacional média foi 35 semanas. Cerca de 12% tinham antecedentes de prematuridade. As condições associadas à prematuridade tardia foram: trabalho de parto prematuro (67%), ruptura prematura das membranas (39,6%), síndromes hipertensivas (25,3%), sem haver diferença da frequência por subgrupos de idade gestacional. CONCLUSÕES: trabalho de parto prematuro espontâneo, ruptura prematura das membranas e síndromes hipertensivas foram as condições clínicas mais frequentemente associadas com prematuridade tardia.

Safety concerns for the use of calcium channel blockers in pregnancy for the treatment of spontaneous preterm labour and hypertension: a systematic review and meta-regression analysis

BACKGROUND

Calcium channel blockers (CCBs) are not licensed for use in pregnancy but are used without robust surveillance to treat hypertension in pregnancy and preterm labour. The objective of this study was to evaluate the fetomaternal safety of CCB in pregnancy by a quantitative systematic review.

METHODS

Medline (1996-2005), EMBASE (1996-2003), BIOSIS (1993-2003), Current contents (1995-2003), DERWENT DRUGFILE (1983-2003) and Cochrane Library (2005: issue 3). The number of women reporting an adverse event was used to compute a percentage of the total number of women in whom the occurrence of that event or confirmation of its absence was reported. Meta-regression with generalised estimation equations modelling explored reasons for heterogeneity, seeking factors that increased the rates of the most commonly reported adverse events.

FINDINGS

Of 269 relevant reports, including 5607 women, adverse fetomaternal events varied according to the total dose of nifedipine and study design. Adverse events were highest amongst women given more than 60 mg total dose of nifedipine [odds ratio (OR) 3.78, 95% confidence interval (CI) 1.27-11.2, p = 0.017] and in reports from case series compared to controlled studies (OR 2.45, 95% CI 1.17-5.15, p = 0.018).

INTERPRETATION

Adverse event rates generated from this study provide an evidence base for clinical guidelines and informed patient consent for CCB use in pregnancy.

Atosiban vs ritodrine used prophylactically with cerclage in ICSI pregnancies to prevent pre-term birth in women identified as being at high risk on the basis of transvaginal ultrasound scan

Our objective was to compare the effectiveness and safety of atosiban and ritodrine, in pregnancies obtained by intracytoplasmic sperm injection (ICSI) undergoing cervical cerclage. Data from a prospective study were compared with those from a retrospective study. Sixteen ICSI pregnant women, 20-24 weeks' gestation and maternal age >18 years, received atosiban (bolus dose 6.75 mg i.v., followed by 300 microg/min i.v. for 3 h and 100 microg/min i.v. for 45 h). Cervical cerclage was performed 3 h after starting atosiban. The control group (group B) of 16 ICSI pregnant women were matched and received ritodrine hydrochloride (100-350 microg/min) for 48 h. Cervical cerclage was performed after 24 h. Pre-term rupture of membranes occurred within 48 h of cervical cerclage in one woman receiving atosiban and in four women receiving ritodrine. There was no significant difference in terms of pregnancies not delivered at 48 h (short-term tocolysis) and at 7 days (long-term tocolysis). However, there was a significantly higher incidence of maternal tachycardia with ritodrine compared with atosiban (p < 0.001). The mean gestational age at delivery was significantly higher for atosiban compared with ritodrine (36 vs 33 weeks; p < 0.001). The neonatal outcome was poorer for ritodrine than atosiban, as there were very low birth weight infants (p = 0.008), resulting in lower Apgar scores (p = 0.005) and there were more neonates requiring a long stay in the neonatal intensive care unit (p = 0.005). We conclude that atosiban is associated with a significantly lower incidence of maternal tachycardia and improved neonatal outcome compared with ritodrine.

Is long-term tocolysis effective for threatened premature labour?

There is some controversy regarding the optimum duration of tocolysis. This retrospective multicentre study was performed to evaluate whether long-term (> 2 days) tocolysis is effective in treating threatened premature labour. A total of 1147 eligible patients were grouped according to whether or not tocolytics were given, and according to route of administration and whether or not ritodrine (the standard tocolytic regimen in Japan) or other tocolytic was given. They were then further stratified into three subgroups, using the Baumgarten and Gruber tocolysis index (TI), to assess the efficacy of tocolysis treatment according to the risk of premature labour. Prolongation of gestation was significantly longer in patients treated with tocolytics for > 2 days compared with the unmedicated, bed-rest group. In women receiving tocolysis, the mean duration of prolonged gestation was 2.2 times longer in the intermediate-risk TI group and 3.1 times longer in the high-risk TI group compared with the unmedicated group. In the patients who received tocolysis, IV ritodrine was used in 86% of cases and was considered safe and effective for prolonging gestation in cases of threatened premature labour.

HCG--A new kid on the block in prematurity prevention

Human chorionic gonadotropin (HCG) is a molecule with multiple endocrine, paracrine, and immunoregulatory actions. Its importance for the enhancement of fertility, successful implantation, and survival of the conceptus in early gestation is recognized. However, studies conducted worldwide in recent years indicate that HCG may also play a significant role in maintaining pregnancy well after the first trimester. Emerging evidence suggests that different biomolecular and physiologic effects of HCG are concordantly directed toward inhibition of myometrial contractility to maintain pregnancy. These studies have prompted preliminary animal and human testing of HCG for the prevention of preterm birth. This article reviews the current knowledge as well as the future perspectives on HCG as a useful new tool in prematurity prevention.

Breast carcinoma during pregnancy

BACKGROUND

Breast carcinoma during pregnancy (BCP) is a difficult clinical situation, as it appears to put the health of the mother in conflict with that of the fetus.

METHODS

An international expert meeting was conducted to form guidelines on how to diagnose and treat women with BCP.

RESULTS

The goal for treatment of the pregnant woman with breast carcinoma is the same as that of the nonpregnant breast carcinoma patient: local control of disease and prevention of systemic metastases. However, certain treatment modalities need to be modified because of the potential for adverse effects on the fetus. There is evidence to support the safety of anthracycline-based chemotherapy during the second and third trimesters of pregnancy (Oxford Level of Evidence [LOE] 2b). Because of the lack of evidence, the expert opinion was not to recommend the routine use of newer cytotoxic drugs like the taxanes during pregnancy (LOE 5).

CONCLUSION

The recommendations provided should help to reach informed decision making by the patient. The ongoing prospective collection of data on BCP, such as that at the University of Texas M.D. Anderson Cancer Center (UTMDACC) and that of the German Breast Group/Breast International Group (GBG/BIG), is necessary to further our knowledge regarding the treatment of this unique group of breast carcinoma patients.