Bishop score

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Bishop score
Synonyms Cervix score
Purposepre-labor scoring system to assist in predicting whether induction of labor will be required

Bishop score, also Bishop's score or cervix score, is a pre-labor scoring system to assist in predicting whether induction of labor will be required. [1] It has also been used to assess the likelihood of spontaneous preterm delivery. [2] The Bishop score was developed by Professor Emeritus of Obstetrics and Gynecology, Edward Bishop, and was first published in August 1964. [1] [3]

Contents

Components

The total score is calculated by assessing the following five components on manual vaginal examination by a trained professional:

The Bishop score grades patients who would be most likely to achieve a successful induction. The duration of labor is inversely correlated with the Bishop score; “A Bishop score of 9 conveys a high likelihood for a successful induction. For research purposes, a Bishop score of 4 or less identifies an unfavorable cervix and may be an indication for cervical ripening.”

Excerpt From Williams Obstetrics, 25th Edition F. Gary Cunningham, Kenneth J. Leveno, Steven L. Bloom, Jodi S. Dashe, Barbara L. Hoffman, Brian M. Casey and Catherine Y. Spong This material may be protected by copyright.

They can be remembered with the mnemonic: Call PEDS For Parturition = Cervical Position, Effacement, Dilation, Softness; Fetal Station.

Scoring

The examiner assigns a score to each component of 0 to 2 or 0 to 3. The highest possible score is 13 and the lowest possible score is 0.

Bishop score [1]
ParameterScoreDescription
0123
Cervical positionPosteriorMiddleAnteriorThe position of the cervix changes with menstrual cycles and also tends to become more anterior (nearer the opening of the vagina) as labour becomes closer.
Cervical consistencyFirmMediumSoftIn primigravid women, the cervix is typically tougher and resistant to stretching, much like a balloon that has not been previously inflated (it feels like the bottom of a chin). With subsequent vaginal deliveries, the cervix becomes less rigid and allows for easier dilation at term.
Cervical effacement 0-30%40-50%60-70%80+%Effacement translates to how 'thin' the cervix is. The cervix is normally approximately three centimetres long, as it prepares for labour and labour continues the cervix will efface until it is 'fully effaced' (paper-thin).
Cervical dilation Closed1–2 cm3–4 cm5+cmDilation is a measure of how open the cervical os is. It is usually the most important indicator of progression through the first stage of labour. Dilation is measured by way of a digital cervical exam with the care providers fingers. Dilation is described using centimetres; closed, 1cm, 2cm, 3cm, etc until fully dilated at 10 cm.
Fetal station−3−2−1, 0+1, +2Fetal station describes the position of the fetus's head in relation to the distance from the ischial spines, which are approximately 3-4 centimetres inside the vagina and are not usually felt. Health professionals visualise where these spines are and use them as a reference point. Negative numbers indicate that the head is further inside than the ischial spines and positive numbers show that the head is below the level of the ischial spines.

Interpretation

A score of 5 or less suggests that labour is unlikely to start on its own during the next few days. A score of 9 or more indicates that labour will most likely commence spontaneously in the next few days. [4] Scores between 5 and 9 require additional consideration and professional judgement for clinical management.

A Bishop's score 6 or less often indicates that induction (e.g., with controlled-release prostaglandin E2/prostin gel [Cervidil], intravaginal gel [Prostin], intracervical gel [Prepidil]) is unlikely to be successful. [5] Some sources indicate that only a score of 8 or greater is reliably predictive of a successful induction.

The score can be recalculated as the pregnancy progresses.

Modified Bishop score

According to the Modified Bishop's pre-induction cervical scoring system, effacement has been replaced by cervical length in cm, with scores as follows: 0 for >3 cm, 1 for >2 cm, 2 for >1 cm, 3 for >0 cm. [6] Cervical length may be easier and more accurate to measure and have less inter-examiner variability.

Another modification for the Bishop's score is the modifiers. Points are added or subtracted according to special circumstances as follows:

See also

Related Research Articles

<span class="mw-page-title-main">Cervix</span> Lower part of the uterus in the human female reproductive system

The cervix or cervix uteri is the lower part of the uterus (womb) in the human female reproductive system. The cervix is usually 2 to 3 cm long and roughly cylindrical in shape, which changes during pregnancy. The narrow, central cervical canal runs along its entire length, connecting the uterine cavity and the lumen of the vagina. The opening into the uterus is called the internal os, and the opening into the vagina is called the external os. The lower part of the cervix, known as the vaginal portion of the cervix, bulges into the top of the vagina. The cervix has been documented anatomically since at least the time of Hippocrates, over 2,000 years ago.

<span class="mw-page-title-main">Childbirth</span> Expulsion of a fetus from the pregnant mothers uterus

Childbirth, also known as labour, parturition and delivery, is the completion of pregnancy where one or more babies exits the internal environment of the mother via vaginal delivery or caesarean section. In 2019, there were about 140.11 million human births globally. In the developed countries, most deliveries occur in hospitals, while in the developing countries most are home births.

<span class="mw-page-title-main">Misoprostol</span> Medication to induce abortion and treat ulcers

Misoprostol is a synthetic prostaglandin medication used to prevent and treat stomach and duodenal ulcers, induce labor, cause an abortion, and treat postpartum bleeding due to poor contraction of the uterus. It is taken by mouth when used to prevent gastric ulcers in people taking nonsteroidal anti-inflammatory drugs (NSAID). For abortions it is used by itself or in conjunction with mifepristone or methotrexate. By itself, effectiveness for abortion is between 66% and 90%. For labor induction or abortion, it is taken by mouth, dissolved in the mouth, or placed in the vagina. For postpartum bleeding it may also be used rectally.

A pessary is a prosthetic device inserted into the vagina for structural and pharmaceutical purposes. It is most commonly used to treat stress urinary incontinence to stop urinary leakage and to treat pelvic organ prolapse to maintain the location of organs in the pelvic region. It can also be used to administer medications locally in the vagina or as a method of contraception.

Labor induction is the process or treatment that stimulates childbirth and delivery. Inducing (starting) labor can be accomplished with pharmaceutical or non-pharmaceutical methods. In Western countries, it is estimated that one-quarter of pregnant women have their labor medically induced with drug treatment. Inductions are most often performed either with prostaglandin drug treatment alone, or with a combination of prostaglandin and intravenous oxytocin treatment.

Rupture of membranes (ROM) or amniorrhexis is a term used during pregnancy to describe a rupture of the amniotic sac. Normally, it occurs spontaneously at full term either during or at the beginning of labor. Rupture of the membranes is known colloquially as "breaking [one's] water," especially when induced rather than spontaneous, or as one's "water breaking". A premature rupture of membranes (PROM) is a rupture of the amnion that occurs at full term and prior to the onset of labor. In cases of PROM, options include expectant management without intervention, or interventions such as oxytocin or other methods of labor induction, and both are usually accompanied by close monitoring of maternal and fetal health. Preterm premature rupture of membranes (PPROM) is when water breaks both before the onset of labor and before the pregnancy's 37 week gestation. In the United States, more than 120,000 pregnancies per year are affected by a premature rupture of membranes, which is the cause of about one third of preterm deliveries.

<span class="mw-page-title-main">Atosiban</span> Chemical compound

Atosiban, sold under the brand name Tractocile among others, is an inhibitor of the hormones oxytocin and vasopressin. It is used as an intravenous medication as a labour repressant (tocolytic) to halt premature labor. It was developed by Ferring Pharmaceuticals in Sweden and first reported in the literature in 1985. Originally marketed by Ferring Pharmaceuticals, it is licensed in proprietary and generic forms for the delay of imminent preterm birth in pregnant adult women.

Cervical dilation is the opening of the cervix, the entrance to the uterus, during childbirth, miscarriage, induced abortion, or gynecological surgery. Cervical dilation may occur naturally, or may be induced surgically or medically.

Bloody show or show is the passage of a small amount of blood or blood-tinged mucus through the vagina near the end of pregnancy. It is caused by thinning and dilation of the cervix, leading to detachment of the cervical mucus plug that seals the cervix during pregnancy and tearing of small cervical blood vessels, and is one of the signs that labor may be imminent. The bloody show may be expelled from the vagina in pieces or altogether and often appears as a jelly-like piece of mucus stained with blood. Although the bloody show may be alarming at first, it is not a concern of patient health after 37 weeks gestation.

Dilation and evacuation (D&E) is the dilation of the cervix and surgical evacuation of the uterus after the first trimester of pregnancy. It is a method of abortion as well as a common procedure used after miscarriage to remove all pregnancy tissue.

Fetal fibronectin (fFN) is a fibronectin protein produced by fetal cells. It is found at the interface of the chorion and the decidua. Fetal fibronectin is found normally in vaginal fluid in early pregnancy prior to 22 weeks due to normal growth and development of tissues at the junction of the uterus and amniotic sac. It may also be found in vaginal fluid after 36 weeks as labor approaches. However, fFN should not be detected between 22 and 36 weeks.

<span class="mw-page-title-main">Prelabor rupture of membranes</span> Medical condition

Prelabor rupture of membranes (PROM), previously known as premature rupture of membranes, is breakage of the amniotic sac before the onset of labor. Women usually experience a painless gush or a steady leakage of fluid from the vagina. Complications in the baby may include premature birth, cord compression, and infection. Complications in the mother may include placental abruption and postpartum endometritis.

<span class="mw-page-title-main">Cervical effacement</span>

Cervical effacement or cervical ripening refers to the thinning and shortening of the cervix. This process occurs during labor to prepare the cervix for dilation to allow the fetus to pass through the vagina. While this a normal, physiological process that occurs at the later end of pregnancy, it can also be induced through medications and procedures.

<span class="mw-page-title-main">Cervical cerclage</span> Obstetrics medical procedure

Cervical cerclage, also known as a cervical stitch, is a treatment for cervical weakness, when the cervix starts to shorten and open too early during a pregnancy causing either a late miscarriage or preterm birth. In women with a prior spontaneous preterm birth and who are pregnant with one baby, and have shortening of the cervical length less than 25 mm, a cerclage prevents a preterm birth and reduces death and illness in the baby.

Cervical weakness, also called cervical incompetence or cervical insufficiency, is a medical condition of pregnancy in which the cervix begins to dilate (widen) and efface (thin) before the pregnancy has reached term. Definitions of cervical weakness vary, but one that is frequently used is the inability of the uterine cervix to retain a pregnancy in the absence of the signs and symptoms of clinical contractions, or labor, or both in the second trimester. Cervical weakness may cause miscarriage or preterm birth during the second and third trimesters. It has been estimated that cervical insufficiency complicates about 1% of pregnancies, and that it is a cause in about 8% of women with second trimester recurrent miscarriages.

Prostaglandin E<sub>2</sub> Chemical compound

Prostaglandin E2 (PGE2), also known as dinoprostone, is a naturally occurring prostaglandin with oxytocic properties that is used as a medication. Dinoprostone is used in labor induction, bleeding after delivery, termination of pregnancy, and in newborn babies to keep the ductus arteriosus open. In babies it is used in those with congenital heart defects until surgery can be carried out. It is also used to manage gestational trophoblastic disease. It may be used within the vagina or by injection into a vein.

Postterm pregnancy is when a woman has not yet delivered her baby after 42 weeks of gestation, two weeks beyond the typical 40-week duration of pregnancy. Postmature births carry risks for both the mother and the baby, including fetal malnutrition, meconium aspiration syndrome, and stillbirths. 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. Postterm pregnancy is a reason to induce labor.

<span class="mw-page-title-main">Vaginal delivery</span> Delivery through the vagina

A vaginal delivery is the birth of offspring in mammals through the vagina. It is the most common method of childbirth worldwide. It is considered the preferred method of delivery, with lower morbidity and mortality than caesarean sections (C-sections).

<span class="mw-page-title-main">Osmotic dilator</span> Medical device to dilate the uterine cervix

Osmotic dilators are medical implements used to dilate the uterine cervix by swelling as they absorb fluid from surrounding tissue. They may be composed of natural or synthetic materials. A laminaria stick or tent is a thin rod made of the stems of dried Laminaria, a genus of kelp. Laminaria sticks can be generated from Laminaria japonica and Laminaria digitata. Synthetic osmotic dilators are commonly referred to by their brand names, such as Dilapan. Dilapan-S are composed of polyacrylonitrile, a plastic polymer. The hygroscopic nature of the polymer causes the dilator to absorb fluid and expand.

Placental alpha microglobulin-1 (PAMG-1) is a human protein that was first isolated in 1975 from amniotic fluid. PAMG-1 is an important biomarker for the detection of premature rupture of fetal membrane (PROM) The high concentration of PAMG-1 in amniotic fluid means it can be used to detect if this fluid is present in the cervico-vaginal discharge of pregnant women; the presence of PAMG-1 in the discharge suggests that amniotic fluid is present, and therefore suggests that PROM has occurred. PAMG-1 was originally referred to as specific alpha-1 globulin of placenta.

References

  1. 1 2 3 Bishop, Edward H. (August 1964). "Pelvic Scoring for Elective Induction". Obstetrics & Gynecology. 24 (2): 266–268. PMID   14199536.
  2. Newman RB, Goldenberg RL, Iams JD, et al. (September 2008). "Preterm Prediction Study: Comparison of the Cervical Score and Bishop Score for Prediction of Spontaneous Preterm Delivery". Obstet Gynecol. 112 (3): 508–15. doi:10.1097/AOG.0b013e3181842087. PMC   2728002 . PMID   18757646.
  3. "AGOS-Edward H. Bishop". Archived from the original on 2015-06-24. Retrieved 2015-06-21.
  4. Tenore J (2003). "Methods for cervical ripening and induction of labor". Am Fam Physician. 67 (10): 2123–8. PMID   12776961. (Incomplete) Free Text Archived 2008-05-16 at the Wayback Machine .
  5. Cat.Inist
  6. Dutta DC. Text Book of Obstetrics. 6ed. New Central Book Agency. 2001. ISBN   978-81-7381-142-5.