Premature rupture of membranes (PROM), is defined as rupture of membranes (breakage of the amniotic sac), commonly called breaking of the mother’s waters, more than 1 hour before the onset of labour. The sac (consisting of 2 membranes, the chorion and amnion) contains amniotic fluid, which surrounds and protects the fetus in the uterus (womb). After rupture, the amniotic fluid leaks out of the uterus, through the vagina. The foetal membranes serve as a barrier to ascending infection. Once the membranes rupture, both the mother and fetus are at risk of infection and of other complications.
Women with PROM usually experience a painless gush of fluid leaking out from the vagina, but sometimes a slow steady leakage occurs instead.
Premature rupture of membranes (PROM) refers to a patient who is beyond 37 weeks’ gestation and has presented with rupture of membranes (ROM) prior to the onset of labour. Preterm premature rupture of membranes (PPROM) is ROM prior to 37 weeks’ gestation. Prolonged ROM is any ROM that persists for more than 24 hours prior to the onset of labour.
Eighty-five percent of neonatal morbidity and mortality is a result of prematurity. PPROM is associated with 30-40% of preterm deliveries and is the leading identifiable cause of preterm delivery. PPROM complicates 3% of all pregnancies and occurs in approximately 150,000 pregnancies yearly in the United States
Despite the common TV image of ROM occurring in every pregnancy, PROM occurs in approximately 10% of pregnancies. Patients with PROM present with leakage of fluid, vaginal discharge, vaginal bleeding, and pelvic pressure, but they are not having contractions. Most patients (90%) enter spontaneous labour within 24 hours when they experience ROM at term. The major question regarding management of these patients is whether to allow them to enter labour spontaneously or to induce labour. The management of these patients depends on a number of factors including patient’s wishes, however, the major maternal risk at this stage is intrauterine infection. The risk of intrauterine infection increases with the duration of ROM. Evidence supports the idea that induction of labour, as opposed to expectant management, decreases the risks.
Premature preterm rupture of membranes (PPROM) occurring from 24-37 weeks’ gestation is far more difficult to manage than premature rupture of membranes (PROM) at term. Prematurity is the principal risk to the fetus, while infection morbidity and its complications are the primary maternal risks. The initial evaluation of premature preterm rupture of membranes (PPROM) should include a sterile speculum examination to document ROM. Cervical cultures including Chlamydia trachomatis and Neisseria gonorrhoeae should be obtained. ROM diagnosis needs to be confirmed. Digital vaginal examinations should be avoided. Ultrasonography should be performed to confirm gestational age,
Maternal vital signs should be documented as well as continuous foetal monitoring initially to establish foetal status. Once the decision to manage a patient expectantly has been made, the institution of broad-spectrum antibiotics should be considered. Multiple trials have examined the advantages and disadvantages of using antibiotics and the choice of antibiotics. In most studies, use of antibiotics has been associated with prolongation of pregnancy and reduction in infant and maternal morbidity. However, a few studies have reported increased neonatal morbidity.
The RCOG recommends –
Antenatal prophylactic antibiotics for women with PPROM
• Offer women with PPROM oral erythromycin 250 mg 4 times a day for a maximum of 10 days or until the woman is in established labour (whichever is sooner).
• For women with PPROM who cannot tolerate erythromycin or in whom erythromycin is contraindicated, consider oral penicillin for a maximum of 10 days or until the woman is in established labour (whichever is sooner).
• Do not offer women with PPROM co amoxiclav as prophylaxis for intrauterine infection.
The use of corticosteroids to accelerate lung maturity should be considered in all patients with PPROM with a risk of infant prematurity from 24-34 weeks’ gestation. A single course of corticosteroids is recommended for pregnant women 24-34 weeks’ gestation who are at risk of preterm delivery within 7 days.
Several techniques have been developed in an attempt to artificially reseal the foetal membranes and prevent leakage of amniotic fluid including, among others, intra-amniotic injection of platelets and cryoprecipitate (amnio-patch), sealing the cervical canal, and laser coagulation. However, there is as yet no effective and safe technique to achieve this goal.
References
1. Mercer BM, Arheart KL. Antimicrobial therapy in expectant management of preterm premature rupture of the membranes. Lancet. 1995;346:1271–9.
2. Hannah ME, Ohlsson A, Farine D, Hewson SA, Hodnett ED, Myhr TL, et al. Induction of labor compared with expectant management for prelabor rupture of the membranes at term. N Engl J Med. 1996;334:1005–10.
3. Schucker JL, Mercer BM. Midtrimester premature rupture of the membranes. Semin Perinatol. 1996;20:389–400.
4. American College of Obstetricians and Gynecologists. Premature rupture of membranes. Clinical management guidelines for obstetrician-gynecologists. ACOG practice bulletin no. 1. Int J Gynaecol Obstet. 1998;63:75–84.
5. Mercer BM. Preterm premature rupture of the membranes. Obstet Gynecol. 2003;101:178–93.
6. Smith CV, Greenspoon J, Phelan JP, Platt LD. Clinical utility of the nonstress test in the conservative management of women with preterm spontaneous premature rupture of the membranes. J Reprod Med. 1987;32:1–4.
7. Cox SM, Leveno KJ. Intentional delivery versus expectant management with preterm ruptured membranes at 30–34 weeks’ gestation. Obstet Gynecol. 1995;86:875–9.
8. ACOG Committee on Practice Bulletins-Obstetrics, authors. Clinical management guidelines for obstetrician-gynecologists. (ACOG Practice Bulletin No. 80: premature rupture of membranes).Obstet Gynecol. 2007;109:1007–1019.
9. Spinillo A, Montanari L, Sanpaolo P, et al. Fetal growth and infant neuro-developmental outcome after preterm premature rupture of membranes. Obstet Gynecol. 2004;103:1286–1293
10. Healy AJ, Veille JC, Sciscione A, et al. The timing of elective delivery in preterm premature rupture of the membranes: a survey of members of the Society of Maternal-Fetal Medicine. Am J Obstet Gynecol. 2004;190:1479–1481.
11. 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;109:634–640
12. Mercer BM. Preterm premature rupture of the membranes: current approaches to evaluation and management. Obstet Gynecol Clin North Am. 2005;32:411–428.
13. Gold RB, Goyert GL, Schwartz DB, et al. Conservative management of second-trimester postamniocentesis fluid leakage. Obstet Gynecol. 1989;74:745–747.
14. Lewi L, Van Schoubroeck D, Van Ranst M, et al. Successful patching of iatrogenic rupture of the fetal membranes. Placenta. 2004;25:352–356.
15. Bonanno C, Fuchs K, Wapner RJ. Single versus repeat courses of antenatal steroids to improve neonatal outcomes: risks and benefits. Obstet Gynecol Surv. 2007;62:261–271.
16. Kenyon S, Boulvain M, Neilson J. Antibiotics for preterm rupture of the membranes: a systematic review. Obstet Gynecol. 2004;104:1051–1057.