The following signs and symptoms confirms the occurrence of preterm labor:

• Spotting or early bleeding due to the early effacement of the cervix.
• Progressive and frequent uterine contractions. usually 5 or more contractions per hour.
• Low back pain secondary to the impinging head of the baby in the birth canal.
• Fluid leak or gush primarily due to the premature rupture of membranes.
• Bloody mucous discharge suggests that the cervix is starting to open.

• Pain

  Pregnant moms, especially those who are pregnant with multiples, will feel aches and pains all the time. In cases of preterm labor, the symptoms may be so mild at first that they are brushed off as common pregnancy pains. [babymed.com]

  Hypertension and epigastric pain could not be controlled after the operation. [ncbi.nlm.nih.gov]

  Lower backache If you’re nearing the home stretch of your pregnancy, back pain may be all too familiar. [monbaby.com]

  You need to see a health care provider right away if you have: Spotting and cramps in your abdomen Contractions with lower back pain or pressure in your groin or thighs Fluid that leaks from your vagina in a trickle or a gush Bright red bleeding from [medlineplus.gov]

• Cerebral Palsy

  Premature labor can increase risk of intraventricular hemorrhage in neonates; intraventricular hemorrhage may result in neurodevelopmental disability (eg, cerebral palsy ). [merckmanuals.com]

  Magnesium Sulfate: A drug that may help prevent cerebral palsy when it is given to women in preterm labor who may deliver before 32 weeks of pregnancy. [m.acog.org]

• Inflammation

  KEYWORDS: Genital sampling; Histological chorioamnionitis; Intra-amniotic infection; Intra-amniotic inflammation; Preterm labor [Indexed for MEDLINE] Free full text [ncbi.nlm.nih.gov]

• Crying

  A lot of women are afraid of "crying wolf," but it is much better to be incorrect than to be in preterm labor and not being treated. [verywellfamily.com]

  RDS) – a condition caused by immature lungs that makes breathing difficult difficulty controlling body temperature problems with eating and digesting food infection jaundice bleeding in the brain hearing and vision problems difficulty making sounds, crying [beaumont.org]

  […] disorders secondary to both physical and environmental factors.[40] Children with cerebral palsy have significantly higher rates of sleep disturbance than typically developing children.[41] Babies with cerebral palsy who have stiffness issues might cry [en.wikipedia.org]

• Collapse

  These include: Respiratory distress syndrome (RDS): A condition involving irregular breathing and a lack of surfactant – a substance that helps prevent the lungs from collapsing – in the lungs. [ada.com]

  This lack of surfactant causes the airways of the lungs to collapse whenever the baby breathes out, so that it takes a lot of effort to reinflate the lungs. [myvmc.com]

  […] with beta-agonists, nifedipine also lowers the risk of RDS, necrotizing enterocolitis, intraventricular hemorrhage, neonatal jaundice, and NICU admission.21 Nifedipine poses few maternal or fetal risks, but its use with magnesium sulfate has led to CV collapse [uspharmacist.com]

• Abdominal Pain

  METHODS: Prospectively collected data of pregnant women presenting with symptoms of preterm labor (abdominal pain or tightening) at 24-34 weeks' gestation were retrieved from the research databases of the EQUIPP and PETRA studies for subanalysis. [ncbi.nlm.nih.gov]

  Wellbeing of Women ELS Jane Currie (A David primary supervisor) “Do women presenting with abdominal pain and negative urine dipstick tests in pregnancy have subclinical urinary tract infection?” [ucl.ac.uk]

  These symptoms include an increase in the amount of vaginal discharge, vaginal bleeding/spotting, a change in the type of discharge (eg. more watery or mucous-like), abdominal pain /cramping similar to period pains, and more than four contractions in [myvmc.com]

  These symptoms include an increase in the amount of vaginal discharge, vaginal bleeding/spotting, a change in the type of discharge (eg. more watery or mucous-like), abdominal pain/cramping similar to period pains, and more than four contractions in one [healthengine.com.au]

• Hearing Impairment

  Long term prognosis Preterm babies have higher risk of :  neurological disability  Low IQ  Visual and hearing impairment.• Severity of handicap is inversely related to gestational age at birth. 41. [slideshare.net]

  Survivors sometimes suffer long-term health consequences, including chronic lung disease, vision and hearing impairment, cerebral palsy, and developmental problems. Most premature babies are born between 34 and 37 weeks. [babycenter.com]

• Back Pain

  Lower backache If you’re nearing the home stretch of your pregnancy, back pain may be all too familiar. [monbaby.com]

  Preterm labor, on the other hand, will present with rhythmic contractions, increased vaginal discharge, breaking of the bag of waters, lower back pain, and cramps of the abdomen. [babymed.com]

  Symptoms of preterm labor include contractions, cramps, back pain, or leaking of fluid from the vagina. Preterm labor may result in preterm birth. Babies born too early are at risk for many serious health problems. [stlouischildrens.org]

  You need to see a health care provider right away if you have: Spotting and cramps in your abdomen Contractions with lower back pain or pressure in your groin or thighs Fluid that leaks from your vagina in a trickle or a gush Bright red bleeding from [medlineplus.gov]

• Fracture

  Longer off-label administration of magnesium for tocolysis, which is approved only for the prevention of seizures in preeclampsia, can lead to low calcium levels and osteopenia or fractures in the baby, the agency explained. [medpagetoday.com]

  This further affects a child's mobility, strength, experience of pain, and can lead to missed schooling or child abuse suspicions.[21] These children generally have fractures in the legs, whereas non-affected children mostly fracture their arms in the [en.wikipedia.org]

  In these cases, fetuses were exposed to the drug for nearly 10 weeks, on average, with neonates developing transient osteopenia and fractured bones. [emedicine.medscape.com]

• Thigh Pain

  The critical signs include contractions greater than 4 per hour, rhythmic back or thigh pain, increasing pelvic pressure, unusual discharge, vaginal spotting/bleeding, or rupture of membranes, tenesmus, and urgency. [www1.cgmh.org.tw]

  The critical signs of recurrent preterm labor include contractions greater than 4 per hour, rhythmic back or thigh pain, increasing pelvic pressure, unusual discharge, vaginal spotting/bleeding, or rupture of membranes. [emedicine.medscape.com]

• Confusion

  If there is any confusion because you have irregular periods or you had some early spotting, ultrasound examinations can help the doctor try and arrive at the correct age of the baby you are carrying. [everydayfamily.com]

  However, there are other signs and symptoms that aren’t always as obvious as they can be confused with other forms of pain and issues with pregnancy, including: Dull, constant pain in the lower back Abdominal cramps Rupturing of membranes (water breaking [birthinjuryguide.org]

  Signs of early labour Premature labour should not be confused with Braxton Hicks contractions. These are irregular, painless, “practice” contractions that come and go throughout pregnancy. True premature labour contractions are constant. [parent24.com]

  Sometimes you may confuse the baby’s movement with contractions, especially as the baby grows. [babies.sutterhealth.org]

• Hyperactivity

  Some have emotional outbursts or are hyperactive. They may have learning or reading problems in school. The earlier a baby is born, the more likely they are to have problems. [webmd.com]

  Observations to report immediately include hyperactivity of the fetus; vaginal bleeding in excess of a heavy show; a rapid and irregular pulse and drop in blood pressure; sudden rise in blood pressure; and headache, visual disturbances, extreme restlessness [medical-dictionary.thefreedictionary.com]

• Neonatal Seizures

  Monitoring has shown to reduce intrapartum death and neonatal seizures. Additionally, the neonatal care team should be informed of the status of the patient to ensure appropriate personnel and equipment are available if required. [ncbi.nlm.nih.gov]

• Vaginal Discharge

  If you have any of these signs or symptoms before your 37th week of pregnancy, you may be experiencing preterm labor: Change in your vaginal discharge (watery, mucus or bloody) or more vaginal discharge than usual Pressure in your pelvis or lower belly [marchofdimes.org]

  The results of vaginal discharge tests and maternal serum C-reactive protein (CRP) level at admission, placental biopsy, and perinatal outcomes were searched. The prevalence of abnormal vaginal flora was calculated. [ncbi.nlm.nih.gov]

  Preterm labor, on the other hand, will present with rhythmic contractions, increased vaginal discharge, breaking of the bag of waters, lower back pain, and cramps of the abdomen. [babymed.com]

• Cesarean Section

  Cesarean section was performed 9 days later after spontaneous rupture of membranes with excellent outcome. The same approach is suggested for similar cases. [ncbi.nlm.nih.gov]

  In this case, labor is induced or Cesarean section delivery occurs before a baby is full term because of health concerns to the mother or baby. [cincinnatichildrens.org]

• Regular Uterine Contractions

  This communication describes a case of a pregnant woman who had an allergic reaction and regular uterine contractions after the ingestion of lobster meat, to which she was known to be allergic. [ncbi.nlm.nih.gov]

  Definition Preterm labor : Regular uterine contractions with cervical effacement, dilation, or both before 37 weeks gestation. [amboss.com]

  Signs & Symptoms of Preterm Labor The most common signs that you may give birth to a preemie include regular uterine contractions. Some women describe these symptoms as severe menstrual-type cramps in the lower part of the abdomen (tummy area). [healthcare.utah.edu]

  This study aimed to evaluate the effectiveness of nifedipine versus a placebo for inhibiting uterine contraction in threatened preterm labor. [dovepress.com]

  First stage (stage of dilation): This is the period from the onset of regular uterine contractions to full dilation and effacement of the cervix. This stage averages 12 hr in primigravidas and 8 hr in multiparas. [medical-dictionary.thefreedictionary.com]

• Pelvic Pain

  If you are entering labor, you may notice symptoms such as a heavy feeling in the pelvis, cramping, spotting or bleeding, backache, and intermittent pelvic pain that lasts 30 to 90 seconds. [nyulangone.org]

  Vaginal bleeding Vaginal discharge that is unusual Severe, persistent, frequent headaches Pain or burning upon urination, or decrease in urination Persistent nausea or vomiting Leakage of fluid from the vagina Sharp pelvic pain or severe cramping Frequent [sidelines.org]

  Back pain: A constant low, dull back pain may be a sign of labor. Increased pelvic pressure: If you feel a significant increase in pressure in your pelvic area, call your doctor. [whattoexpect.com]

The diagnosis of preterm labor precludes with the accurate determination of fetal gestational age that falls beyond 20 weeks and lower than 37 weeks, with concurrent regular contractions and vaginal spotting.

The following tests and procedures may be utilized to help in the diagnosis of preterm labor:

• Pelvic Examination will give the obstetrician an idea of how the baby may present during delivery, estimate the firmness of the uterus, and determine whether the cervix has started to open.
• Ultrasound: A pelvic sonogram can determine the accurate age of the fetus, its relative presentation, amniotic fluid volume, length of cervix and baby’s size.
• Uterine monitor will determine the actual spacing of the uterine contractions.
• Fetal monitoring is used to monitor the fetal heart rate during the course of the labor to determine the child’s well-being.
• Laboratory test: Vaginal swabs may be taken to determine the presence of fibronectin and the possible presence of infectious organisms. 
• Maturity amniocentesis: This laboratory study involves the extraction of amniotic fluid when the age of gestation is beyond 32 weeks to determine the fetal lung age and determine the presence of amniotic fluid infections [6].

The following treatment modalities are done to prevent the progression of preterm labor to preterm delivery:

• Cervical cerclage: This surgical procedure is done to reinforce the cervix and prevent preterm birth in an incompetent cervix condition.
• Corticosteroids: Patients in preterm labor between 24 to 34 weeks of gestation may benefit from betamethasone or dexamethasone injections to hasten the lung maturity of the neonate before preterm birth [7].
• Tocolytics: This group of medications may be given to patients in preterm labor to halt the uterine contractions and its progression. Tocolytics are not routinely given to preterm labor cases beyond 34 weeks, deliveries are postponed till the 37th weeks to significantly lower neonatal mortality and morbidity [8]. The use of magnesium sulfate as a tocolytic agent has been found to decrease the incidence of cerebral palsy and low birth weight infants [9].

Patients with less frequent contraction without bleeding may still be able to tocolyze the preterm labor till term pregnancy. However, patients presenting with rapid contractions with eminent bleeding may have an increased chance to progress to preterm delivery.

The relative prognosis of neonates born through preterm labor varies directly with age of gestation, and varies inversely with the number of congenital defects seen. This prognostic relationship is also true with maternal and neonatal morbidity and mortality ratings respectively.

Complications

The following medical conditions are common complication of preterm labor:

• Preterm delivery
• Premature rupture of membranes
• Premature neonate
• Neonatal sepsis
• Recurrent preterm labor

The progression to preterm labor is influenced by the maternal health, lifestyle and inherent anatomical defects. The following etiologic factors may lead to preterm labor:

• Multiple pregnancy
• Chorioamnionitis
• Severe congenital defects of the fetus
• Hypertension
• Premature rupture of membranes
• Polyhydramnios
• First trimester bleeding
• Cigarette smoking
• Illegal drug use
• Severe psychological and physical Stress
• Obesity
• Previous preeclampsia [1]
• Poor weight gain during pregnancy
• Short cervical length [2]
• Cervical incompetence
• Abnormal uterine shape
• Abruptio placenta and placenta previa

Preterm labor initiates more than half of preterm deliveries and is considered as the leading cause of neonatal mortality in the United States today [3]. Preterm births accounts for the 70% of neonatal morbidity and mortality [4].

The relative risk of preterm births due to preterm labor may be averted by the prompt and early identification of risk factors among mothers with less than 37 weeks of gestation. The active reduction of extreme prematurity (less than 32 weeks) will significantly reduce the mortality, morbidity and the inherent expenses during the delivery [5].

The pathophysiology of preterm labor lies on the nature of the inciting factor that induces labor. Preterm infection like chorioamnionitis or maternal septicemia may trigger uterine labor prematurely. The relative mass of the conceptus pressing against the thinning cervix may be influenced by twining or multiple pregnancies. Consequently, the cervical competence and amniotic fluid volume is also an important contributory factor in the progression of the preterm labor.

Extrinsic factors that trigger neurotransmitter release in the maternal system like cigarette smoking, psychological stress and physical stress may induce premature contractions of the uterus.

Mothers who begin to feel uterine contractions should take a short walk, change position or rest for a few minutes to quell the preterm contractions at home. Frequent false contractions in the preterm period is a risk factor for preterm labor in the late preterm stages (34-36 weeks) [10].

Persistent contraction despite these remedies must be brought in to the nearest obstetric care facility for proper assessment and monitoring. Adequate rest and fluid intake during intermittent uterine contractions may prove to be beneficial in some cases of preterm labor.

Preterm labor is a clinical condition defined as the premature opening of the cervix due to frequent uterine contractions before 37 weeks of gestation. When such event is unabated, this may result to the delivery of a premature baby that may require special care upon birth and may be at risk to long term complications. Mothers who underwent preterm labor may be at risk to another preterm labor on her next pregnancy.

Definition

Preterm labor is defined as the frequent uterine contraction that lead to the opening of the cervix before term pregnancy.

Cause

Multiple pregnancy, infections, stress, cervical incompetence, deficient amniotic fluid, placental abruption, and placenta previa may lead to preterm labor.

Symptoms

Frequent uterine contractions with shorter intervals, bleeding per vagina, cervical effacement and early rupture of membranes are common symptoms.

Diagnosis

Pelvic examination, ultrasound, fetal and uterine monitoring and amniocentesis are used to diagnose preterm labor.

Treatment and follow-up

Cervical cerclage, corticosteroids to enhance fetal lung maturity, and tocolytics to control preterm contractions are the treatment options.

1. Lykke JA, Paidas MJ, Langhoff-Roos J. Recurring complications in second pregnancy.Obstet Gynecol. Jun 2009; 113(6):1217-24.
2. Durnwald CP, Walker H, Lundy JC, Iams JD. Rates of recurrent preterm birth by obstetrical history and cervical length. Am J Obstet Gynecol. Sep 2005; 193(3 Pt 2):1170-4.
3. American College of Obstetricians and Gynecologists. ACOG Practice Bulletin. Assessment of risk factors for preterm birth. Clinical management guidelines for obstetrician-gynecologists. Number 31, October 2001. (Replaces Technical Bulletin number 206, June 1995; Committee Opinion number 172, May 1996; Committee Opinion number 187, September 1997; Committee Opinion number 198, February 1998; and Committee Opinion number 251, January 2001). Obstet Gynecol. Oct 2001; 98(4):709-16.
4. ACOG practice bulletin. Management of preterm labor. Number 43, May 2003. Int J Gynaecol Obstet. Jul 2003; 82(1):127-35.
5. Eden RD, Penka A, Britt DW, Landsberger EJ, Evans MI. Re-evaluating the role of the MFM specialist: lead, follow, or get out of the way. J Matern Fetal Neonatal Med. Oct 2005; 18(4):253-8.
6. Romero R, Miranda J, Chaiworapongsa T, et al. A novel molecular microbiologic technique for the rapid diagnosis of microbial invasion of the amniotic cavity and intra-amniotic infection in preterm labor with intact membranes. Am J Reprod Immunol. Apr 2014; 71(4):330-58.
7. Crowther CA, McKinlay CJ, Middleton P, Harding JE. Repeat doses of prenatal corticosteroids for women at risk of preterm birth for improving neonatal health outcomes. Cochrane Database Syst Rev. Jun 15 2011; 6:CD003935.
8. Cheng Y, Kaimal A, Bruckner T, Hallaron D, Caughey A. Perinatal morbidity associated with late preterm deliveries compared with deliveries between 37 and 40 weeks of gestation. BJOG. Nov 2011; 118(12):1446-1454.
9. Conde-Agudelo A, Romero R. Antenatal magnesium sulfate for the prevention of cerebral palsy in preterm infants less than 34 weeks' gestation: a systematic review and metaanalysis. Am J Obstet Gynecol. Jun 2009; 200(6):595-609.
10. Chao TT, Bloom SL, Mitchell JS, McIntire DD, Leveno KJ. The diagnosis and natural history of false preterm labor. Obstet Gynecol. Dec 2011; 118(6):1301-8.