Magnesium Sulfate Versus Nifedipine for the Acute Tocolysis of Preterm Labor: A Prospective, Randomized Trial

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.

ClinicalTrials.gov Identifier: NCT00185900

Recruitment Status : Completed

First Posted : September 16, 2005

Results First Posted : October 2, 2018

Last Update Posted : November 19, 2018

View this study on Beta.ClinicalTrials.gov

Sponsor:

Information provided by (Responsible Party):

Yasser Yehia El-Sayed, Stanford University

Study Type	Interventional
Study Design	Allocation: Randomized; Intervention Model: Parallel Assignment; Masking: None (Open Label); Primary Purpose: Treatment
Condition	Obstetric Labor, Premature
Interventions	Drug: Magnesium Sulfate Drug: Nifedipine
Enrollment	192

Participant Flow

Recruitment Details
Pre-assignment Details


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Period Title: Overall Study
Started	92	100
Completed	92	100
Not Completed	0	0

Baseline Characteristics

Arm/Group Title		Magnesium Sulfate	Nifedipine	Total
Arm/Group Description		Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...	Total of all reporting groups
Arm/Group Description		Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.	Total of all reporting groups
Overall Number of Baseline Participants		92	100	192
Baseline Analysis Population Description		[Not Specified]
Baseline Analysis Population Description		[Not Specified]
Age, Continuous Mean (Standard Deviation) Unit of measure: Years
	Number Analyzed	92 participants	100 participants	192 participants
		26.6 (6.8)	26.3 (6.3)	26.5 (6.6)
Sex: Female, Male Measure Type: Count of Participants Unit of measure: Participants
	Number Analyzed	92 participants	100 participants	192 participants
	Female	92 100.0%	100 100.0%	192 100.0%
	Male	0 0.0%	0 0.0%	0 0.0%
Region of Enrollment Measure Type: Number Unit of measure: Participants
United States	Number Analyzed	92 participants	100 participants	192 participants
United States		92	100	192

Outcome Measures

1.Primary Outcome


Title	Number of Participants With Prevention of Preterm Delivery for 48 Hours With Attainment of Uterine Quiescence
Description	Uterine quiescence defined by 12 hours of six or fewer contractions pe...
Description	Uterine quiescence defined by 12 hours of six or fewer contractions per hour and no further cervical change within 48 hours of tocolytic initiation.
Time Frame	48 hours after administration of study medication.

Outcome Measure Data

Analysis Population Description

[Not Specified]


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	92	100
Measure Type: Count of Participants Unit of Measure: Participants
	80 87.0%	72 72.0%

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Magnesium Sulfate, Nifedipine
	Comments	[Not Specified]
	Type of Statistical Test	Superiority
	Comments	[Not Specified]

Statistical Test of Hypothesis	P-Value	0.01
	Comments	[Not Specified]
	Method	Chi-squared
	Comments	[Not Specified]

2.Secondary Outcome


Title	Time to Uterine Quiescence
Description	Uterine quiescence was defined by 12 hours of six of fewer contraction...
Description	Uterine quiescence was defined by 12 hours of six of fewer contractions per hour and no further cervical change.
Time Frame	Until delivery, up to 42 weeks of gestation

Outcome Measure Data

Analysis Population Description

[Not Specified]


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	92	100
Mean (Standard Deviation) Unit of Measure: hours
	8.4 (6.5)	6.1 (6.3)

3.Secondary Outcome


Title	Gestational Age at Delivery
Description	Presented as weeks
Description	Presented as weeks
Time Frame	Until delivery, up to 42 weeks of gestation

Outcome Measure Data

Analysis Population Description

[Not Specified]


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	92	100
Mean (Standard Deviation) Unit of Measure: weeks
	35.8 (3.4)	36.0 (3.1)

4.Secondary Outcome


Title	Neonatal Birth Weight
Description	Presented as grams
Description	Presented as grams
Time Frame	Until delivery, up to 42 weeks of gestation

Outcome Measure Data

Analysis Population Description

Data included twins, so the group totals are greater than seen in the Overall Number of Participants Analyzed


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	106	110
Mean (Standard Deviation) Unit of Measure: grams
	2550 (802)	2650 (698)

5.Secondary Outcome


Title	Serious Maternal Adverse Effect
Description	A composite of any of the following: chest pain, pulmonary edema, shor...
Description	A composite of any of the following: chest pain, pulmonary edema, shortness of breath or hypotension.
Time Frame	From study enrollment until discharge from delivery hospital, up to 30 days after delivery.

Outcome Measure Data

Analysis Population Description

[Not Specified]


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	92	100
Measure Type: Count of Participants Unit of Measure: Participants
	20 21.7%	10 10.0%

6.Secondary Outcome


Title	Composite Neonatal Morbidity
Description	Defined as any of the following: respiratory distress syndrome, intrav...
Description	Defined as any of the following: respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, sepsis or fetal/neonatal death.
Time Frame	From delivery until discharge from the hospital, up to 30 days of age

Outcome Measure Data

Analysis Population Description

Data included twins, so the group totals are greater than seen in the Overall Number of Participants Analyzed.


Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description:	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description:	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
Overall Number of Participants Analyzed	106	110
Measure Type: Count of Participants Unit of Measure: Participants
	27 25.5%	22 20.0%

Adverse Events

Time Frame	From study enrollment until discharge from the delivery hospital, up to 30 days after delivery.
Adverse Event Reporting Description	Adverse events were assessed by patient interview from a list of adverse effects and chart review.

Arm/Group Title	Magnesium Sulfate	Nifedipine
Arm/Group Description	Preterm labor treatment with Magnes...	Preterm labor treatment with Nifedi...
Arm/Group Description	Preterm labor treatment with Magnesium Sulfate. Magnesium Sulfate: Preterm labor treatment with Magnesium Sulfate 4 gram bolus followed by 2 gm per hour infusion. 2 Gm bolus as needed and/or rate increase up to 4gm per hour were allowed at the discretion of the treating physician.	Preterm labor treatment with Nifedipine. Nifedipine: Preterm labor treatment with Nifedipine 10 mg. sublingually every 20 minutes for three doses, followed by 20 mg. orally every 4 or 6 hours.
All-Cause Mortality
	Magnesium Sulfate	Nifedipine
	Affected / at Risk (%)	Affected / at Risk (%)
Total	0/92 (0.00%)	0/100 (0.00%)
Serious Adverse Events Serious Adverse Events
	Magnesium Sulfate	Nifedipine
	Affected / at Risk (%)	Affected / at Risk (%)
Total	25/92 (27.17%)	12/100 (12.00%)
Cardiac disorders
Chest pain ^†	7/92 (7.61%)	4/100 (4.00%)
Respiratory, thoracic and mediastinal disorders
Shortness of breath ^†	13/92 (14.13%)	5/100 (5.00%)
Pulmonary edema ^†	3/92 (3.26%)	0/100 (0.00%)
Vascular disorders
Hypotension ^†	2/92 (2.17%)	3/100 (3.00%)
† Indicates events were collected by systematic assessment
Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events	0%
	Magnesium Sulfate	Nifedipine
	Affected / at Risk (%)	Affected / at Risk (%)
Total	29/92 (31.52%)	22/100 (22.00%)
Cardiac disorders
Palpitations ^†	1/92 (1.09%)	0/100 (0.00%)
Eye disorders
Blurry Vision ^†	12/92 (13.04%)	0/100 (0.00%)
Double vision ^†	3/92 (3.26%)	0/100 (0.00%)
Gastrointestinal disorders
Nausea ^†	29/92 (31.52%)	6/100 (6.00%)
Vomiting ^†	24/92 (26.09%)	5/100 (5.00%)
Heartburn ^†	6/92 (6.52%)	6/100 (6.00%)
Nervous system disorders
Lethargy ^†	27/92 (29.35%)	3/100 (3.00%)
Dizziness ^†	16/92 (17.39%)	3/100 (3.00%)
Headache ^†	11/92 (11.96%)	22/100 (22.00%)
Skin and subcutaneous tissue disorders
Flushing ^†	20/92 (21.74%)	1/100 (1.00%)
† Indicates events were collected by systematic assessment

Limitations and Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

Results Point of Contact

Layout table for Results Point of Contact information

Name/Title:	Dr. Anna Girsen
Organization:	Stanford University
Phone:	(650) 725-5720
EMail:	agirsen@stanford.edu

Publications of Results:

Lyell DJ, Pullen K, Campbell L, Ching S, Druzin ML, Chitkara U, Burrs D, Caughey AB, El-Sayed YY. Magnesium sulfate compared with nifedipine for acute tocolysis of preterm labor: a randomized controlled trial. Obstet Gynecol. 2007 Jul;110(1):61-7. doi: 10.1097/01.AOG.0000269048.06634.35.

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Wilson A, Hodgetts-Morton VA, Marson EJ, Markland AD, Larkai E, Papadopoulou A, Coomarasamy A, Tobias A, Chou D, Oladapo OT, Price MJ, Morris K, Gallos ID. Tocolytics for delaying preterm birth: a network meta-analysis (0924). Cochrane Database Syst Rev. 2022 Aug 10;8(8):CD014978. doi: 10.1002/14651858.CD014978.pub2.

Layout table for additonal information

Responsible Party:	Yasser Yehia El-Sayed, Stanford University
ClinicalTrials.gov Identifier:	NCT00185900
Other Study ID Numbers:	76145
First Submitted:	September 12, 2005
First Posted:	September 16, 2005
Results First Submitted:	February 13, 2018
Results First Posted:	October 2, 2018
Last Update Posted:	November 19, 2018

To Top