Other things to keep in mind that may present similarly to premature rupture of membranes are the following:

- Urinary incontinence: leakage of small amounts of urine is common in the last part of pregnancy

- Normal vaginal secretions of pregnancy

- Increased sweat or moisture around the perineum

- Increased cervical discharge: this can happen when there is a genital tract infection

- Semen

- Douching

- Vesicovaginal fistula: an abnormal connection between the bladder and the vagina

- Loss of the mucus plug

Premature rupture of membranes (PROM), or pre-labor rupture of membranes, is a condition that can occur in pregnancy. It is defined as rupture of membranes (breakage of the amniotic sac), commonly called breaking of the mother's water(s), more than 1 hour before the onset of labor. 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.

Women with PROM usually experience a painless gush of fluid leaking out from the vagina, but sometimes a slow steady leakage occurs instead.

When premature rupture of membranes occurs at or after 37 weeks completed gestational age (full-term or term), there is minimal risk to the fetus and labor typically starts soon after.

If rupture occurs before 37 weeks, it is called preterm premature rupture of membranes (PPROM), and the fetus and mother are at greater risk for complications. PPROM causes one-third of all preterm births, and babies born preterm (before 37 weeks) can suffer from the complications of prematurity, including death.

Premature rupture of the membranes provides a path for bacteria to enter the womb and puts both the mother and fetus at risk for life-threatening infection. Low levels of fluid around the fetus also increase the risk of umbilical cord compression and can interfere with lung and body formation in early pregnancy.

Women who suspect they might have experienced premature rupture of membranes should be evaluated promptly in the hospital to determine whether a rupture of membranes has indeed occurred, and to be treated appropriately to avoid infection and other complications.

Women with placenta previa often present with painless, bright red vaginal bleeding. This commonly occurs around 32 weeks of gestation, but can be as early as late mid-trimester. 51.6% of women with placenta previa have antepartum haemorrhage. This bleeding often starts mildly and may increase as the area of placental separation increases. Previa should be suspected if there is bleeding after 24 weeks of gestation. Bleeding after delivery occurs in about 22% of those affected.

Women may also present as a case of failure of engagement of fetal head.

Postmaturity symptoms vary. The most common are dry skin, overgrown nails, creases on the baby's palms and soles of their feet, minimal fat, abundant hair on their head, and either a brown, green, or yellow discoloration of their skin. Doctors diagnose post-mature birth based on the baby's physical appearance and the length of the mother's pregnancy. However, some postmature babies may show no or few signs of postmaturity.

Hyperemesis gravidarum is the presence of severe and persistent vomiting, causing dehydration and weight loss. It is more severe than the more common morning sickness and is estimated to affect 0.5–2.0% of pregnant women.

Placenta praevia is when the placenta attaches inside the uterus but near or over the cervical opening. Symptoms include vaginal bleeding in the second half of pregnancy. The bleeding is bright red and tends not to be associated with pain. Complications may include placenta accreta, dangerously low blood pressure, or bleeding after delivery. Complications for the baby may include fetal growth restriction.

Risk factors include pregnancy at an older age and smoking as well as prior cesarean section, labor induction, or termination of pregnancy. Diagnosis is by ultrasound. It is classified as a complication of pregnancy.

For those who are less than 36 weeks pregnant with only a small amount of bleeding recommendations may include bed rest and avoiding sexual intercourse. For those after 36 weeks of pregnancy or with a significant amount of bleeding, cesarean section is generally recommended. In those less than 36 weeks pregnant, corticosteroids may be given to speed development of the babies lungs. Cases that occur in early pregnancy may resolve on their own.

It affects approximately 0.5% of pregnancies. After four cesarean section it, however, effects 10% of pregnancies. Rates of disease have increased over the late 20th century and early 21st century. The condition was first described in 1685 by Paul Portal.

Postterm pregnancy is the condition of a baby that has not yet been born after 42 weeks of gestation, two weeks beyond the normal 40. Post-mature births can carry risks for both the mother and the infant, including fetal malnutrition. After the 42nd week of gestation, the placenta, which supplies the baby with nutrients and oxygen from the mother, starts aging and will eventually fail. If the fetus passes its fecal matter, which is not typical until after birth, and breathes it in, it could become sick with meconium aspiration syndrome. Postterm pregnancy may be a reason to induce labor.

Gestational diabetes is when a woman without diabetes develops high blood sugar levels during pregnancy.

In ICD-10, early pregnancy bleeding (code O20.9) refers to obstetrical hemorrhage before 20 completed weeks of gestational age.

First trimester bleeding, is obstetrical hemorrhage in the first trimester (0 weeks-12 weeks of gestational age). First trimester bleeding is a common occurrence and estimated to occur in approximately 25% of all (clinically recognized) pregnancies.

Differential diagnosis of first trimester bleeding is as follows, with the mnemonic AGE IS Low (during first trimester):

- Abortion (spontaneous), also referred to as miscarriage. One study came to the result that the risk of miscarriage during the course of the pregnancy with just spotting during the first trimester was 9%, and with light bleeding 12%, compared to 12% in pregnancies without any first trimester bleeding. However, heavy first trimester bleeding was estimated to have a miscarriage risk of 24%.

- Gestational trophoblastic neoplasia

- Ectopic pregnancy, which implies a pregnancy outside the uterus, commonly in the fallopian tube, which may lead to bleeding internally that could be fatal if untreated. In cases where there is heavy bleeding and an obstetric ultrasonography assists in diagnosing a pregnancy of unknown location (no visible intrauterine pregnancy), it has been estimated that approximately 6% have an underlying ectopic pregnancy.

- Implantation bleeding

- Chorionic hematoma

- Spotting

- Lower GU tract causes

- Vaginal bleed

- Cervical bleed

Other causes of early pregnancy bleeding may include:

- Postcoital bleeding, which is vaginal bleeding after sexual intercourse that can be normal with pregnancy

- Iatrogenic causes, or bleeding due to medical treatment or intervention, such as sex steroids, anticoagulants, or intrauterine contraceptive devices

- Infection

Obstetrical bleeding also known as obstetrical hemorrhage and maternal hemorrhage, refers to heavy bleeding during pregnancy, labor, or the postpartum period. Bleeding may be vaginal or less commonly but more dangerously, internal, into the abdominal cavity. Typically bleeding is related to the pregnancy itself, but some forms of bleeding are caused by other events.

The most frequent cause of maternal mortality worldwide is severe hemorrhage with 8.7 million cases occurring in 2015 and 83,000 of those events resulting in maternal death. Between 2003 and 2009, hemorrhage accounted for 27.1% of all maternal deaths globally

Symptoms of a rupture may be initially quite subtle. An old cesarean scar may undergo dehiscence; but with further labor the woman may experience abdominal pain and vaginal bleeding, though these signs are difficult to distinguish from normal labor. Often a deterioration of the fetal heart rate is a leading sign, but the cardinal sign of uterine rupture is loss of fetal station on manual vaginal exam. Intra-abdominal bleeding can lead to hypovolemic shock and death. Although the associated maternal mortality is now less than one percent, the fetal mortality rate is between two and six percent when rupture occurs in the hospital.

In pregnancy uterine rupture may cause a viable abdominal pregnancy. This is what accounts for most abdominal pregnancy births.

- Abdominal pain and tenderness. The pain may not be severe; it may occur suddenly at the peak of a contraction. The woman may describe a feeling that something "gave way" or "ripped."

- Chest pain, pain between the scapulae, or pain on inspiration—Pain occurs because of the irritation of blood below the woman's diaphragm

- Hypovolemic shock caused by haemorrhage— Falling blood pressure, tachycardia, tachypnea, pallor, cool and clammy skin, and anxiety. The fall in blood pressure is often a late sign of haemorrhage

- Signs associated with fetal oxygenation, such as late deceleration, reduced variability, tachycardia, and bradycardia

- Absent fetal heart sounds with a large disruption of the placenta; absent fetal heart activity by ultrasound examination

- Cessation of uterine contractions

- Palpation of the fetus outside the uterus (usually occurs only with a large, complete rupture). The fetus is likely to be dead at this point.

- Signs of an abdominal pregnancy

- Post-term pregnancy

Generally it is preferable to describe specific signs in lieu of declaring "fetal distress" that include:

- Decreased movement felt by the mother

- Meconium in the amniotic fluid ("meconium stained fluid")

- Non-reassuring patterns seen on cardiotocography:

- increased or decreased fetal heart rate (tachycardia and bradycardia), especially during and after a contraction

- decreased variability in the fetal heart rate

- late decelerations

- Biochemical signs, assessed by collecting a small sample of baby's blood from a scalp prick through the open cervix in labor

- fetal metabolic acidosis

- elevated fetal blood lactate levels (from fetal scalp blood testing) indicating the baby has a lactic acidosis

Some of these signs are more reliable predictors of fetal compromise than others. For example, cardiotocography can give high false positive rates, even when interpreted by highly experienced medical personnel. Metabolic acidosis is a more reliable predictor, but is not always available.

In medicine (obstetrics), the term fetal distress refers to the presence of signs in a pregnant woman—before or during childbirth—that suggest that the fetus may not be well. Because of its lack of precision, the term is eschewed in modern American obstetrics.

Antepartum bleeding, also known as antepartum haemorrhage or prepartum hemorrhage, is genital bleeding during pregnancy from the 28th week (sometimes defined as from the 20th week) gestational age to term.

It can be associated with reduced fetal birth weight.

In regard to treatment, it should be considered a medical emergency (regardless of whether there is pain) and medical attention should be sought immediately, as if it is left untreated it can lead to death of the mother and/or fetus.

Locked twins is a rare complication of multiple pregnancy where two fetuses become interlocked during presentation before birth. It occurs in roughly 1 in 1,000 twin deliveries and 1 in 90,000 deliveries overall. Most often, locked twins are delivered via Caesarean section, given that the condition has been diagnosed early enough. The fetal mortality rate is high for the twin that presents first, with over 50% being stillborn.

Preterm birth causes a range of problems.

The main categories of causes of preterm birth are preterm labor induction and spontaneous preterm labor. Signs and symptoms of preterm labor include four or more uterine contractions in one hour. In contrast to false labour, true labor is accompanied by cervical dilatation and effacement. Also, vaginal bleeding in the third trimester, heavy pressure in the pelvis, or abdominal or back pain could be indicators that a preterm birth is about to occur. A watery discharge from the vagina may indicate premature rupture of the membranes that surround the baby. While the rupture of the membranes may not be followed by labor, usually delivery is indicated as infection (chorioamnionitis) is a serious threat to both fetus and mother. In some cases, the cervix dilates prematurely without pain or perceived contractions, so that the mother may not have warning signs until very late in the birthing process.

A review into using uterine monitoring at home to detect contractions and possible preterm births in women at higher risk of having a preterm baby found that it did not reduce the number of preterm births. The research included in the review was poor quality but it showed that home monitoring may increase the number of unplanned antenatal visits and may reduce the number of babies admitted to special care when compared with women receiving normal antenatal care.

Obstructed labour, also known as labour dystocia, is when, even though the uterus is contracting normally, the baby does not exit the pelvis during childbirth due to being physically blocked. Complications for the baby include not getting enough oxygen which may result in death. It increases the risk of the mother getting an infection, having uterine rupture, or having post-partum bleeding. Long term complications for the mother include obstetrical fistula. Obstructed labour is said to result in prolonged labour, when the active phase of labour is longer than twelve hours.

The main causes of obstructed labour include: a large or abnormally positioned baby, a small pelvis, and problems with the birth canal. Abnormal positioning includes shoulder dystocia where the anterior shoulder does not pass easily below the pubic bone. Risk factors for a small pelvis include malnutrition and a lack of exposure to sunlight causing vitamin D deficiency. It is also more common in adolescence as the pelvis may not have finished growing. Problems with the birth canal include a narrow vagina and perineum which may be due to female genital mutilation or tumors. A partograph is often used to track labour progression and diagnose problems. This combined with physical examination may identify obstructed labour.

The treatment of obstructed labour may require cesarean section or vacuum extraction with possible surgical opening of the symphysis pubis. Other measures include: keeping the women hydrated and antibiotics if the membranes have been ruptured for more than 18 hours. In Africa and Asia obstructed labor affects between two and five percent of deliveries. In 2015 about 6.5 million cases of obstructed labour or uterine rupture occurred. This resulted in 23,000 maternal deaths down from 29,000 deaths in 1990 (about 8% of all deaths related to pregnancy). It is also one of the leading causes of stillbirth. Most deaths due to this condition occur in the developing world.

Preterm infants usually show physical signs of prematurity in reverse proportion to the gestational age. As a result, they are at risk for numerous medical problems affecting different organ systems.

- Neurological problems include apnea of prematurity, hypoxic-ischemic encephalopathy (HIE), retinopathy of prematurity (ROP), developmental disability, transient hyperammonemia of the newborn, cerebral palsy and intraventricular hemorrhage, the latter affecting 25 percent of babies born preterm, usually before 32 weeks of pregnancy. Mild brain bleeds usually leave no or few lasting complications, but severe bleeds often result in brain damage or even death. Neurodevelopmental problems have been linked to lack of maternal thyroid hormones, at a time when their own thyroid is unable to meet postnatal needs.

- Cardiovascular complications may arise from the failure of the ductus arteriosus to close after birth: patent ductus arteriosus (PDA).

- Respiratory problems are common, specifically the respiratory distress syndrome (RDS or IRDS) (previously called hyaline membrane disease). Another problem can be chronic lung disease (previously called bronchopulmonary dysplasia or BPD).

- Gastrointestinal and metabolic issues can arise from neonatal hypoglycemia, feeding difficulties, rickets of prematurity, hypocalcemia, inguinal hernia, and necrotizing enterocolitis (NEC).

- Hematologic complications include anemia of prematurity, thrombocytopenia, and hyperbilirubinemia (jaundice) that can lead to kernicterus.

- Infection, including sepsis, pneumonia, and urinary tract infection

A study of 241 children born between 22 and 25 weeks who were currently of school age found that 46 percent had severe or moderate disabilities such as cerebral palsy, vision or hearing loss and learning problems. 34 percent were mildly disabled and 20 percent had no disabilities, while 12 percent had disabling cerebral palsy.

Vasa praevia, also spelled vasa previa, is a condition in which babies' blood vessels cross or run near the internal opening of the uterus. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.

Risk factors include in vitro fertilization.

Vasa praevia occurs in about 0.6 per 1000 pregnancies. The term "vasa previa" is derived from the Latin; "vasa" means vessels and "previa" comes from "pre" meaning "before" and "via" meaning "way". In other words, vessels lie before the baby in the birth canal and in the way.

The main causes of obstructed labour include: a large or abnormally positioned baby, a small pelvis, and problems with the birth canal. Abnormal positioning includes shoulder dystocia where the anterior shoulder does not pass easily below the pubic bone. Risk factors for a small pelvis include malnutrition and a lack of exposure to sunlight causing vitamin D deficiency. while problems with the birth canal include a narrow vagina and perineum which may be due to female genital mutilation or tumors.

Uterine rupture is a serious event during childbirth by which the integrity of the myometrial wall is breached. In an incomplete rupture the peritoneum is still intact. With a complete rupture the contents of the uterus may spill into the peritoneal cavity or the broad ligament. A uterine rupture is a life-threatening event for mother and baby.

A uterine rupture typically occurs during active labor, but may also develop during late pregnancy.

Uterine dehiscence is a similar condition, but involves fewer layers, less bleeding, and less risk.

There are two types of locked twins: breech/vertex and vertex/vertex. In breech/vertex presentations, which are much more common, the first twin is in the breech position, presenting feet-first, and the second is in the cephalic (vertex) position, presenting in the normal head-first manner. In these cases, the chin of the first twin locks behind the chin of the second twin while in the uterus or birth canal, preventing vaginal delivery. In vertex/vertex presentations, where both twins are positioned for head-first delivery, the two heads become locked at the pelvic brim, preventing either fetus from passing through the pelvic inlet in a vaginal delivery.

Contributing factors to the interlocking of twins include uterine hypertonicity, small fetal size, and reduced levels of amniotic fluid following rupture of the membranes. It is more likely to occur in women with large pelvises, young primigravidae (young women in their first pregnancy), and pregnancies with monoamniotic twins.

Placenta accreta occurs when all or part of the placenta attaches abnormally to the myometrium (the muscular layer of the uterine wall). Three grades of abnormal placental attachment are defined according to the depth of attachment and invasion into the muscular layers of the uterus:

- Accreta – chorionic villi attach to the myometrium, rather than being restricted within the decidua basalis.

- Increta – chorionic villi invade into the myometrium.

- Percreta – chorionic villi invade through the perimetrium (uterine serosa).

Because of abnormal attachment to the myometrium, placenta accreta is associated with an increased risk of heavy bleeding at the time of attempted vaginal delivery. The need for transfusion of blood products is frequent, and hysterectomy is sometimes required to control life-threatening hemorrhage.

Bloody show is the passage of a small amount of blood or blood-tinged mucus through the vagina near the end of pregnancy. It can occur just before labor or in early labor as the cervix changes shape, freeing mucus and blood that occupied the cervical glands or cervical os. Bloody show is a relatively common feature of pregnancy, and it does not signify increased risk to the mother or baby . A larger amount of bleeding, however, may signify a more dangerous, abnormal complication of pregnancy, such as placental abruption or placenta previa. Large amounts of bleeding during or after childbirth itself may come from uterine atony or laceration of the cervix, vagina, or perineum.

Three common signs of the onset of labor are:

1. A bloody show

2. Rupture of membranes ("Water breaking")

3. Onset of tightenings or contractions

However, these may occur at any time and in any order. Some women neither experience a bloody show nor have their "water break" until well into advanced labor. Therefore, neither bloody show nor rupture of membranes are required to establish labor.

Vasa previa is seen more commonly with velamentous insertion of the umbilical cord, accessory placental lobes (succenturiate or bilobate placenta), multiple gestation, IVF pregnancy. In IVF pregnancies incidences as high as one in 300 have been reported. The reasons for this association are not clear, but disturbed orientation of the blastocyst at implantation, vanishing embryos and the increased frequency of placental morphological variations in in vitro fertilisation pregnancies have all been postulated.