Understanding Arom And Prom: Rupture Of Membranes Explained

During pregnancy, the amniotic sac, a fluid-filled sac that surrounds and protects the foetus, sometimes breaks prematurely, a condition known as premature rupture of membranes (PROM). PROM refers to the rupture of the amniotic sac before the onset of labour, while preterm premature rupture of membranes (PPROM) occurs when the sac breaks before 37 weeks of gestation. PROM and PPROM can have different causes, and they carry risks such as infection, prematurity, and other complications. The appropriate management of PROM and PPROM depends on the gestational age, with delivery typically recommended after 37 weeks and expectant management or bed rest considered for earlier ruptures.

PROM vs PPROM: PROM is a rupture of the amnion at full term before labour, while PPROM occurs before 37 weeks of gestation

PROM, or premature rupture of membranes, refers to the rupture of the amniotic sac before the onset of labour in women who are beyond 37 weeks' gestation. This is colloquially known as "breaking one's water" or "water breaking". PROM occurs in approximately 8% of pregnancies at term and 1% of deliveries overall, and it is two times more common in African Americans.

PPROM, or preterm premature rupture of membranes, refers to the rupture of the amniotic sac before 37 weeks' gestation. PPROM occurs in approximately 3% of all pregnancies and is the leading identifiable cause of preterm delivery, accounting for 30-40% of preterm deliveries. It is associated with a prenatal morbidity and mortality rate exceeding 20%.

The rupture of membranes can result from a variety of factors, including physiologic weakening of the membranes, intramniotic infection, uterine contractions, uterine overdistension, nutritional deficiencies, connective tissue disorders, and more. The risk factors for PPROM include a history of PPROM, short cervical length, vaginal bleeding during pregnancy, low body mass index, low socioeconomic status, tobacco smoking, illicit drug use, and more.

The diagnosis of PROM and PPROM is made through a combination of clinical history, physical examination, and laboratory tests. The management of PROM and PPROM depends on the gestational age and the presence of any complications. Expectant management and induction of labour are considered, with the goal of preventing infections and ensuring the best possible outcome for both mother and fetus.

Causes: PPROM is often due to medical conditions or pregnancy complications, while PROM is usually caused by the pressure of contractions

Premature rupture of membranes (PROM) is the rupture of the amniotic sac before the onset of labour. When this occurs before 37 weeks of gestation, it is referred to as preterm premature rupture of membranes (PPROM).

PPROM is often caused by medical conditions or pregnancy complications, such as infections of the uterus, cervix, or vagina, and too much stretching of the amniotic sac. Other factors that may be linked to PPROM include low socioeconomic status, a history of sexually transmitted diseases, uterine distension, and tobacco smoking.

On the other hand, PROM is usually caused by the pressure of contractions or a natural weakening of the membranes near the end of pregnancy.

In both cases of PROM and PPROM, the biggest sign to watch for is fluid leaking from the vagina. This may leak slowly or gush out. If you think your membranes have ruptured, contact your healthcare provider right away.

Diagnosis: A speculum exam can be used to collect a fluid sample for testing, and an ultrasound can check the foetus's position

A speculum exam is a standard part of the diagnosis process for a suspected rupture of membranes. During the speculum exam, the patient is inspected for any signs of cervicitis, umbilical cord prolapse, vaginal bleeding, or fetal prolapse. The cervix is also examined to assess cervical dilatation and effacement.

The speculum exam is a sterile procedure, and cultures may be obtained during the exam. Visualization of amniotic fluid passing from the cervical canal and pooling in the vagina typically confirms a diagnosis of membrane rupture. The pooling test is one of the main methods of detecting a rupture of membranes.

A speculum can also be used to collect a sample of vaginal fluid for testing. This fluid is then tested to determine if amniotic fluid is present. The pH of the fluid is tested, as amniotic fluid has a higher pH than normal vaginal secretions. An arborization test can also be performed on the fluid, which looks for a fern-like pattern caused by salt crystallization in the amniotic fluid.

An ultrasound can be used to check the foetus's position and evaluate its health. Ultrasounds are a routine part of prenatal care and can be performed transabdominally or transvaginally. The foetus's heart, head, and spine are evaluated, along with other body parts. Ultrasounds can also determine the gestational age of the baby and whether the foetus is growing properly.

Treatment: Treatment depends on the gestational age and foetus health. For PROM after 37 weeks, labour is usually induced, while PPROM may be treated with bed rest, medication and monitoring

Treatment for PROM and PPROM depends on the gestational age and foetal health. If a pregnant woman's waters break without the onset of contractions (PROM) at 37 weeks of pregnancy or more, there are two options: inducing labour so that the baby is born as soon as possible, or waiting for labour to start naturally. Inducing labour is usually the preferred option, as it may reduce the risk of maternal infection without increasing the risk of a caesarean section.

In the case of PPROM, which occurs when the water breaks before the onset of labour and before 37 weeks of gestation, treatment options include bed rest, medication, and monitoring. The standard of care is inpatient management with antibiotics and monitoring. Bed rest is defined as no more than 1-2 hours per day out of bed, with permitted activities including bathroom use, bathing, and brief ambulation inside the home or hospital. While it has not been shown to be beneficial in the setting of PPROM and has adverse maternal effects, most maternal-fetal medicine specialists recommend it.

Risks: PROM and PPROM increase the risk of premature birth and infection

PROM and PPROM increase the risk of premature birth and infection.

PROM refers to the rupture of the amniotic sac before the onset of labour in patients beyond 37 weeks' gestation. PPROM refers to the same phenomenon but in patients under 37 weeks' gestation.

PPROM is responsible for 30-40% of preterm births and impacts 150,000 women in the US every year. PROM occurs in about 8-10% of all pregnancies.

Infection is a major risk of PROM and PPROM. The risk of intrauterine infection increases with the duration of ruptured membranes. Chorioamnionitis is a serious infection of the placental tissues that can be very dangerous for both mother and baby. It is caused by bacteria ascending from the ruptured amniotic sac and can present in a matter of hours. Chorioamnionitis is very difficult to diagnose, and typically, two or more of the following symptoms are sought: maternal fever, maternal tachycardia, fetal tachycardia, foul-smelling amniotic fluid or vaginal discharge, uterine tenderness, and maternal leukocytosis.

Other complications that may occur with PROM and PPROM include placental abruption, compression of the umbilical cord, and postpartum infection.

Infection risk is also present in the fetus. The amniotic sac holds the baby in the uterus, protecting it from damage and helping to regulate its temperature. The sac also provides a barrier from contaminants, pathogens, and microorganisms that could ascend and cause intra-amniotic infection. Amniotic fluid has bacteriostatic properties that help prevent ascending infection of the intra-amniotic environment.

The risk of premature birth is also increased by PROM and PPROM. The majority of PPROM babies are born prematurely. In the US, PROM complicates about 8% of pregnancies, and PPROM complicates about 1% of deliveries overall.

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