Medical Policy

This document addresses testing for suspected rupture of membranes (ROM) with test kits, such as the AmniSure^® ROM test, which detects placental alpha-1 microglobulin (PAMG-1), a protein marker of amniotic fluid in vaginal secretions; the ROM Plus^® Fetal Membrane Rupture test, which tests both placental protein 12 (PP12) and alpha-fetoprotein (AFP); and the Actim^® PROM test, which tests for insulin-like growth factor binding protein 1 (IGFBP-1).

Not Medically Necessary:

Evaluation of cervicovaginal fluid for specific amniotic fluid protein(s), (for example, placental alpha microglobulin-1 [PAMG-1], placental protein 12 [PP12], alpha-fetoprotein), is considered not medically necessary for all indications, including detection of preterm rupture of membranes.

Placental alpha-1 microglobulin (PAMG-1) has been investigated as a marker for the detection of premature rupture of membranes (PROM). PAMG-1 can also be found in high levels in amniotic fluid and low levels in cervicovaginal discharge when fetal membranes are intact. The AmniSure ROM (Rupture of Membranes) test (AmniSure^® International, LLC, Cambridge, MA) is a rapid, non-instrumented, qualitative immunochromatographic test for in-vitro detection of amniotic fluid in the vaginal secretions of pregnant women. On February 3, 2004 the AmniSure one-step Fetal Membranes Rupture (ROM) test obtained clearance from the U.S. Food and Drug Administration (FDA). This initial clearance was for the in vitro detection of amniotic fluid in vaginal secretions of pregnant women:

AmniSure detects PAMG-1 protein marker of the amniotic fluid in vaginal secretions. The test is for use by health care professionals to aid in the detection of rupture of membranes (ROM) in pregnant women at > 34 weeks gestation when patients report signs, symptoms or complaints suggestive of ROM (FDA, 2004).

The clinical performance of AmniSure was determined by one study involving two sites in which individuals between 34-41 weeks of gestation, without active vaginal bleeding from any source and placenta previa, were evaluated by clinical assessment control and the AmniSure device. The clinical assessment control was considered positive if two out of three tests (nitrazine, ferning, and pooling) were positive. Statistical analysis was available on 159 women with the positive and negative agreements between AmniSure and the control as follows:

Positive agreement = 97.2% (69/71), 95% confidence interval [CI] = (90.2%, 99.7%);
Negative agreement = 97.6% (81/83), 95% CI = (91.6%, 99.7%).

The AmniSure Fetal Membranes Rupture Test was found to be similar to the predicate device in intended use (that is, detection of rupture of membranes in pregnant women). According to the original FDA clearance:

The devices differ in technological characteristics; however, the methodology of the AmniSure device is well-established and raises no concerns with safety or effectiveness. Furthermore, the AmniSure device was found to be in greater than 97% agreement with the standard clinical procedures used to detect rupture of membranes. Therefore, a substantial equivalence determination was granted for the AmniSure Fetal Membranes Rupture Test.

On January 9, 2009, the FDA-cleared indication for use was modified to remove the specification that the device is for use in women at greater than 34 weeks gestation. The updated FDA labeling is as follows:

The Amnisure ROM (rupture of fetal membrane) Test is a rapid, non-instrumented, qualitative immunochromatographic test for the in vitro detection of amniotic fluid in vaginal secretions of pregnant women. Amnisure detects PAMG-1 protein marker of the amniotic fluid in vaginal secretions. The test is for use by health care professionals to aid in the detection of ROM when patients report signs, symptoms or complaints suggestive of ROM (FDA, 2009).

The evidence basis for this change in FDA labeling was provided as follows:

1. The expected values were determined in literature studies and from research performed by the sponsor;
2. Concentration of PAMG-1 in cervical and vaginal secretions of pregnant women without complications was measured and ranged from 0.05 to 0.22 ng/mL;
3. PAMG-1 concentrations in the amniotic fluid fall into 2,000-25,000 ng/mL range.

Pooled data from the 3 studies for less than 34 weeks gestational age showed:
98% agreement with current methods among positive results (95% confidence intervals 91.6% to 99.9%) and 96% agreement with current methods among negative results (95% confidence intervals 86.3 to 98.9).

Pooled data from 3 studies for greater than or equal to 34 weeks showed:
99% agreement with current methods among both positive and negative results (95% confidence intervals of 96.76 to 99.84% and 95.42 to 99.95% for positive and negative results, respectively) (FDA, 2009).

To date, the available published studies that have evaluated the safety and effectiveness of PAMG-1 testing to detect PROM have been limited. In 2005, Cousins conducted a comparative study (n=203) of AmniSure versus standard diagnostic methods for detection of ROM in women suspected of PROM. The AmniSure test was found to have a sensitivity of 98.9%, specificity of 100%, and negative predictive value (NPV) of 99.1% in diagnosing ROM. Test performance was assessed by comparing AmniSure results to clinical history, nitrazine and fern results, presence of pooling, ultrasound evidence of oligohydramnios, and findings from repeated examinations (Cousins, 2005).

A retrospective cohort study examined the frequency and clinical significance of a positive AmniSure test in subjects with preterm labor and intact membranes by sterile speculum examination. A total of 90 subjects with preterm labor and intact membranes underwent AmniSure testing prior to amniocentesis;  64 subjects also underwent fetal fibronectin (fFN) testing. Amniotic fluid (AF) was cultured for aerobic and anaerobic bacteria and genital mycoplasmas and assayed for matrix metalloproteinase-8. AmniSure positive results occurred in 19% of study subjects (17/90). Subjects with a positive AmniSure test had significantly higher rates of adverse pregnancy and neonatal outcomes (for example, impending preterm delivery, intra-amniotic infection/inflammation, and neonatal morbidity) than those with a negative AmniSure test. A positive test was associated with significantly increased risk of intra-amniotic infection and/or inflammation, delivery within 7, 14, or 28 days and spontaneous preterm birth (at less than 35 weeks), among subjects with a negative fFN test. The authors concluded that a positive AmniSure test in subjects with preterm labor and intact membranes is a risk factor for adverse pregnancy outcome, particularly in those with a negative fFN test. However, it was noted that a positive AmniSure test in subjects without symptoms or signs of ROM should not be taken as an indicator that membranes have ruptured (Lee, 2012). Additional cohort, uncontrolled, comparative, and observational studies have demonstrated the accuracy of AmniSure ROM testing, however, no studies have shown how use of this test will impact clinical outcomes, as compared to conventional methods of PROM detection, and further research is needed (Abdelazim, 2012; Birkenmaier, 2012; Lee, 2007; Tagore, 2010).

On November 23, 2011 another ROM test, the ROM Plus^® Fetal Membrane Rupture Test (Clinical Innovations, LLC, Murray, UT) obtained clearance from the FDA through the 510(k) approval process, as substantially equivalent to the predicate device, the AmniSure ROM test. The approved indications for use are as follows:

As a rapid, qualitative imnmunochromatographic test for the in-vitro detection of amniotic fluid in vaginal secretions of' pregnant women with signs and symptoms of ROM. The test detects AFP (alpha-fetoprotein) and PPI12 (placental protein 12 or insulin growth factor binding protein) from amniotic fluid in vaginal secretions. The test is for prescription use by health care professionals to aid in the detection of rupture of membranes (ROM) in pregnant women in conjunction with other signs and symptoms (FDA, 2011).

Notably, the package insert contains the following warning as a special FDA condition for use: “The test may report positive results in patients with intact membranes and, therefore, decisions to induce labor should not be based solely on the ROM Plus test results” (FDA, 2011).

In 2007, another rapid in vitro test, the Actim^® PROM test (Alere^™ Inc., Waltham, MA) obtained 510(k) clearance from the FDA as substantially equivalent to the AmniSure ROM test. The FDA approved indications are as follows:

The Actim PROM test is a visually interpreted, qualitative immunochromatographic rapid test for the detection of amniotic fluid in cervicovaginal secretions during pregnancy. The Actim PROM test detects IGFBP-1, which is a major protein in amniotic fluid and a marker of the presence of amniotic fluid in a cervicovaginal sample. The test is intended for professional use to help diagnose the rupture of fetal membranes (ROM) in pregnant women at >34 weeks gestation when patients report signs, symptoms or complaints suggestive of ROM or if such signs are otherwise observed (FDA, 2007).

On January 9, 2014, the Actim PROM test obtained an updated 510(k) clearance from the FDA for indications to include use of the device in pregnant women > 29 weeks gestational age and to allow use of the device with vaginal swabs collected without use of a speculum, in addition to the current sample type swabs collected with the use of a speculum. No changes to the test itself had been made by the manufacturer (FDA, 2014).

On April 11, 2018, the FDA cleared the PartoSure^™ test (Qiagen, Inc., Germantown, MD), subject to post-approval study results. The PartoSure is another test kit approved for the detection of PAMG-1 in cervicovaginal secretions. The test is indicated:

As an aid to rapidly assess the risk of spontaneous preterm delivery in ≤ 7 days from the time of cervicovaginal sample collection in pregnant women with signs and symptoms of early preterm labor, intact amniotic membranes and minimal cervical dilatation (< 3 cm), sampled between 24 weeks, 0 days and 34 weeks, 6 days gestation in women with a singleton gestation (FDA, 2018).

The FDA labeling for the PartoSure test kit includes test limitations including, but not limited to:

• The PartoSure result should not be interpreted as absolute evidence for the presence or absence of a process that will result in delivery ≤ 7 days from specimen collection.
• The PartoSure test result should always be used in conjunction with information available from the clinical evaluation of the patient and other diagnostic procedures, such as cervical examination, assessment of uterine activity, and evaluation of other risk factors.
• Results should be interpreted with caution when a specimen is obtained from a patient with unconfirmed gestational age.
• PartoSure test results are qualitative and not quantitative. No quantitative interpretation should be made based on the strength of the test or control lines.
• This test should only be used in patients with signs and symptoms of preterm labor.
• At this time, information is insufficient to rule out interference by cervical digital examination; therefore, specimens should be collected prior to digital examinations (FDA, 2018).

The American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin No. 217 entitled, Prelabor Rupture of Membranes was updated in 2020 with no change in position as follows:

Several commercially available tests for amniotic proteins are currently on the market, with reported high sensitivity for PROM. However, false-positive test result rates of 19–30% have been reported in patients with clinically intact membranes and symptoms of labor. These tests are appealing in light of the requirements of regulatory bodies related to Clinical Laboratory Improvement Amendments of 1988 quality standards on the point-of-care methods of clinical assessment such as Nitrazine and fern testing. The studies evaluating these protein tests are problematic because most of them use conventional clinical assessment (pooling, ferning, pH) as controls or gold standards for the diagnosis of rupture of membranes, calling into question their utility in equivocal cases. Additionally, the U.S. Food and Drug Administration released a letter to health care providers in response to adverse events related to their use, including 13 fetal deaths and multiple reports of health complications in pregnant women. The U.S. Food and Drug Administration letter reminded health care providers that these tests should not be used without other clinical assessments because of concerns about “misuse, overreliance, and inaccurate interpretation of lab test results from rupture of membranes tests used to detect rupture of membranes in pregnant women. These can lead to serious adverse events, including fetal death, infection, and other health complications in pregnant women.” At most these test kits should be considered selectively relative to standard methods of diagnosis (ACOG, 2020).

The Royal College of Obstetricians and Gynecologists (RCOG), Scientific Advisory Committee Guideline on Preterm Prelabor Rupture of Membranes concurs with ACOG that:

The diagnosis of PROM is based primarily on the patient's history and physical examination. Patients often report a sudden gush of fluid or continued leakage of fluid. Sterile speculum examination provides a visual inspection of fluid and an opportunity to inspect for cervicitis and umbilical cord or fetal prolapse, cervical dilation and effacement, and to obtain cultures as appropriate… In unusual cases in which the diagnosis remains unclear after physical examination, ultrasonography may be helpful. Management of ROM hinges on knowledge of gestational age and evaluation of the relative risks of preterm birth versus intrauterine infection, abruptio placentae, and cord accident that could occur with expectant management (RCOG, 2006).

The available evidence regarding the use of rapid immunoassay test kit devices to detect PROM is weak. The use of this type of testing has not been widely accepted for detection of premature rupture of membranes and has not been demonstrated to have significant positive impact on clinical outcomes for pregnant individuals and neonates in comparison to the established methods of PROM detection.

PROM complicates approximately 8% of pregnancies and is generally followed by the prompt onset of spontaneous labor and delivery. Risk factors for PROM include previous preterm birth (especially if the cause was PROM), short cervical length (less than 25 mm) during the second trimester, and preterm labor (PTL) or symptomatic contractions in the current pregnancy. PROM can also occur without any identifiable risk factor. The most significant maternal risk of term PROM is intra-uterine infection, a risk that increases with the duration of membrane rupture. Fetal risks associated with term PROM include umbilical cord compression and ascending infection. Membrane rupture that occurs before 37 weeks of gestation is referred to as preterm PROM (PPROM). PPROM complicates only 2% of pregnancies but is associated with 40% of preterm deliveries and can result in significant neonatal morbidity and mortality. The three causes of neonatal death associated with PPROM are prematurity, sepsis and pulmonary hypoplasia. In the absence of clinical history or confirmatory physical exam, PROM can be definitively diagnosed with ultrasonographically-guided transabdominal instillation of indigo carmine dye, followed by observation for passage of blue fluid from the vagina (ACOG, 2007; RCOG, 2006).

Fern test: This term refers to microscopic crystallization of amniotic fluid on drying which is used as one measure of the presence of PROM.

Indigo carmine test: This test involves amniocentesis and instillation of dye into the amniotic cavity. Leakage of blue-stained fluid into the vagina within 20 to 30 minutes, as evidenced by staining of a tampon, is regarded as a definitive diagnosis of PROM or PPROM. This invasive test is currently considered the “Gold Standard” diagnostic for detection of PROM.

Nitrazine test: This test is designed only to confirm an alkaline pH in the cervicovaginal secretions (the pH of the vaginal secretions is generally 4.5–6.0, whereas amniotic fluid usually has a pH of 7.1–7.3), and is the most common test used to diagnose PROM.

Pooling test: This test involves direct visualization of clear fluid in the posterior fornix of the vagina or leakage of fluid from the cervical os which is considered a diagnostic option for detection of PROM.

Premature rupture of membranes (PROM): Rupture of membranes that occurs before the onset of labor.

Preterm premature rupture of membranes (PPROM): Rupture of membranes that occurs before 37 weeks of gestation.

The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services are Not Medically Necessary:

Peer Reviewed Publications:

1. Abdelazim IA1, Abdelrazak KM, Al-Kadi M, Yehia AH, et al. Fetal fibronectin (Quick Check fFN test) versus placental alpha microglobulin-1 (AmniSure test) for detection of premature rupture of fetal membranes. Arch Gynecol Obstet. 2014; 290(3):457-464.
2. Abdelazim IA, Makhlouf HH. Placental alpha microglobulin-1 (AmniSure^(®) test) for detection of premature rupture of fetal membranes. Arch Gynecol Obstet. 2012; 285(4):985-989.
3. Birkenmaier A, Ries JJ, Kuhle J, et al. Placental α-microglobulin-1 to detect uncertain rupture of membranes in a European cohort of pregnancies. Arch Gynecol Obstet. 2012; 285(1):21-25.
4. Bolotskikh V, Borisova V. Combined value of placental alpha microglobulin-1 detection and cervical length via transvaginal ultrasound in the diagnosis of preterm labor in symptomatic patients. J Obstet Gynecol Res. 2017; 43(8):1263-1269.
5. Caramore T, Dresang LT. What is the best way to diagnose rupture of membranes? Evid Based Pract. 2011; 14(6):5.
6. Caughey AB, Robinson JN, Norwitz ER. Contemporary diagnosis and management of preterm premature rupture of membranes. Rev Obstet Gynecol. 2008; 1(1):11-22.
7. Chen FC, Dudenhausen JW. Comparison of two rapid strip tests based on IGFBP-1 and PAMG-1 for the detection of amniotic fluid. Am J Perinatol. 2008; 25(4):243-246.
8. Conde-Agudelo A, Romero R. Cervical phosphorylated insulin-like growth factor binding protein-1 test for the prediction of preterm birth: a systematic review and meta-analysis. Am J Obstet Gynecol. 2016; 214(1):57-73.
9. Ehsanipoor RM, Swank ML, Jwa SC, et al. Placental α-Microglobulin-1 in vaginal secretions of women with evidence of preterm labor. Am J Perinatol. 2016; 33(2):208-213.
10. Eleje GU, Ezugwu EC, Eke AC, et al. Diagnostic performance of placental alpha-microglobulin-1 test in women with prolonged pre-labor rupture of membranes. J Matern Fetal Neonatal Med. 2016; 29(8):1291-1296.
11. Eleje GU, Ezugwu EC, Eke AC, et al. Accuracy and response time of dual biomarker model of insulin-like growth factor binding protein-1/ alpha fetoprotein (Amnioquick duo+) in comparison to placental alpha-microglobulin-1 test in diagnosis of premature rupture of membranes. J Obstet Gynaecol Res. 2017; 43(5):825-833.
12. Fichera A, Prefumo F, Zanardini C, et al. Rapid cervical phIGFBP-1 test in asymptomatic twin pregnancies: Role in mid-pregnancy prediction of spontaneous preterm delivery. Prenat Diagn. 2014; 34(5):450-459.
13. Lee SM, Lee J, Seong HS, et al. The clinical significance of a positive Amnisure test in women with term labor with intact membranes. J Matern Fetal Neonatal Med. 2009; 22(4):305-310.
14. Lee SE, Park JS, Norwitz ER, et al. Measurement of placental alpha-microglobulin-1 in cervicovaginal discharge to diagnose rupture of membranes. Obstet Gynecol. 2007; 109(3):634-640.
15. Lee SM, Romero R, Park JW, et al. The clinical significance of a positive Amnisure test in women with preterm labor and intact membranes. J Matern Fetal Neonatal Med. 2012; 25(9):1690-1698.
16. Marcellin L, Anselem O, Guibourdenche J, et al. Comparison of two bedside tests performed on cervicovaginal fluid to diagnose premature rupture of membranes. J Gynecol Obstet Biol Reprod (Paris). 2011; 40(7):651-656.
17. Mariona FG, Roura LC. The role of placental alpha microglobulin-1 amnisure in determining the status of the fetal membranes; its association with preterm birth. J Matern Fetal Neonatal Med. 2016; 29(6):1016-1020.
18. Melchor JC, Khalil A, Wing D, et al. Prediction of preterm delivery in symptomatic women using PAMG-1, fetal fibronectin and phIGFBP-1 tests: systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2018; 52(4):442-451.
19. Melchor JC, Navas H, Marcos M, et al. Predictive performance of PAMG-1 vs fFN test for risk of spontaneous preterm birth in symptomatic women attending an emergency obstetric unit: retrospective cohort study. Ultrasound Obstet Gynecol. 2018; 51(5):644-649.
20. Ng BK, Lim PS, Shafiee MN, et al. Comparison between AmniSure placental alpha microglobulin-1 rapid immunoassay and standard diagnostic methods for detection of rupture of membranes. Biomed Res Int. 2013; 587438.
21. Nikolova T, Uotila J, Nikolova N, et al. Prediction of spontaneous preterm delivery in women presenting with premature labor: a comparison of placenta alpha microglobulin-1, phosphorylated insulin-like growth factor binding protein-1, and cervical length. Am J Obstet Gynecol. 2018; 219(6):610.e1-610.e9.
22. Palacio M, Kühnert M, Berger R, et al. Meta-analysis of studies on biochemical marker tests for the diagnosis of premature rupture of membranes: comparison of performance indexes. BMC Pregnancy Childbirth. 2014; 14:183.
23. Ramsauer B, Vidaeff AC, Hösli I, et al. The diagnosis of rupture of fetal membranes (ROM): a meta-analysis. J Perinat Med. 2012; 41(3)233-240.
24. Ravi M, Beljorie M, El Masry K. Evaluation of the quantitative fetal fibronectin test and PAMG-1 test for the prediction of spontaneous preterm birth in patients with signs and symptoms suggestive of preterm labor. J Matern Fetal Neonatal Med. 2018; 28:1-6.
25. Rogers LC, Scott L, Block JE. Accurate point-of-care detection of ruptured fetal membranes: Improved diagnostic performance characteristics with a monoclonal/polyclonal immunoassay. Clin Med Insights Reprod Health. 2016; 10:15-18.
26. Santipap M, Phupong V. Combination of three-dimensional ultrasound measurement of fetal adrenal gland enlargement and placental alpha microglobulin-1 for the prediction of the timing of delivery within seven days in women with threatened preterm labor and preterm labor. J Obstet Gynaecol. 2018; 38(8):1054-1059.
27. Sayres W, American Academy of Family Practitioners (AAFP). Preterm labor. Am Fam Physician. 2010; 81(4):477-484.
28. Tagore S, Kwek K. Comparative analysis of insulin-like growth factor binding protein-1 (IGFBP-1), placental alpha-microglobulin-1 (PAMG-1) and nitrazine test to diagnose premature rupture of membranes in pregnancy. J Perinat Med. 2010; 38(6):609-612.
29. Thomasino T, Levi C, Draper M, Neubert AG. Diagnosing rupture of membranes using combination monoclonal/polyclonal immunologic protein detection. J Reproduc Med. 2013; 58(5-6):187-194.
30. Tripathi R, Tyagi S, Mala YM, Singh N, et al. Comparison of rapid bedside tests for phosphorylated insulin-like growth factor-binding protein 1 and fetal fibronectin to predict preterm birth. Int J Gynaecol Obstet. 2016; 135(1):47-50.
31. van der Ham DP, van Teeffelen AS, Mol BW. Prelabor rupture of membranes: overview of diagnostic methods. Curr Opin Obstet Gynecol. 2012; 24(6):408-412.
32. Wing DA, Haeri S, Silber AC, et al. Placental alpha microglobulin-1 compared with fetal fibronectin to predict preterm delivery in symptomatic women. Obstet Gynecol. 2017; 130(6):1183-1191.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Congress of Obstetricians and Gynecologists (ACOG) Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 217: Prelabor Rupture of Membranes. Clinical Management Guidelines for Obstetrician-Gynecologists. Updated 2020. Obstet Gynecol. 2020;135(3):e80-e97. For additional information visit the web site at: http://www.acog.org/. Accessed on June 25, 2024.
2. Cousins LM, Smok DP, Lovett SM, Poeltler DM. AmniSure placental alpha microglobulin-1 rapid immunoassay versus standard diagnostic methods for detection of rupture of membranes. Am J Perinatol. 2005; 22(6):317-320.
3. Di Renzo GC, Roura LC, Facchinetti F, et al.; European Association of Perinatal Medicine-Study Group on “Preterm Birth." Guidelines for the management of spontaneous preterm labor: identification of spontaneous preterm labor, diagnosis of preterm premature rupture of membranes, and preventive tools for preterm birth. J Matern Fetal Neonatal Med. 2011; 24(5):659-667.
4. Royal College of Obstetricians and Gynecologists (RCOG), Scientific Advisory Committee. Preterm prelabor rupture of membranes. Clinical Green Top Guidelines No. 44. London, UK: RCOG. November 2006.
5. U.S. Food and Drug Administration 510(k) Premarket Notification Database. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPMN/pmn.cfm. Accessed on June 25, 2024.
   • Actim PROM and Actim PROM Controls. 510k No. K061886. January 9, 2014.
   • AmniSure™ ROM (Rupture of Fetal Membranes) Test. 510k No. K081767. January 19, 2008.
   • ROM Plus Fetal Membranes Rupture Rest; Rom Plus Quality Control Kit. 510k No. K110605. November 23, 2011.
6. United States Food and Drug Administration (FDA). Center for Devices and Radiological Health (CDRH): PartoSure^™ Placental Alpha Microglobulin-1 Immunoassay (Qiagen Inc., Germantown, MD). Summary of Safety and Effectiveness. No. P160052. Rockville, MD: FDA. April 11, 2018. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpma/pma.cfm?id=P160052. Accessed on June 25, 2024.

Actim PROM
AmniSure ROM
PartoSure Test
Premature Rupture of Membranes
PROM
ROM
ROM Plus, Fetal Membranes Rupture Test
Rupture of Membranes, Premature

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.