Abstract:
A cervical dilation reading apparatus and method of use to accurately and precisely determine cervical dilation measurements during labor and delivery. The apparatus includes a measuring device having a length with a first portion, a second portion, and a third portion, a first attachment band configured to couple with a first finger, the first attachment band having a fixed attachment fixedly engaged with the first portion of the measuring device, and a second attachment band configured to couple with a second finger, the second attachment band having a slidable attachment slidably engaged with the second portion of the measuring device. The method includes providing a cervical dilation reading apparatus, coupling the first attachment band to a first finger and the second attachment band to a second finger, inserting the first and second fingers into the vaginal introitus and locating the cervix and cervical os, placing the first finger on a first side of the cervical os and extending the second finger away from the first finger to a second side, opposite the first side, of the cervical os, thereby extending the length of the measuring device between the first and second fingers to an extended state, ensuring that the measuring device length is equivalent to the distance between the first and second fingers by pulling on the third portion of the measuring device if neccesary, removing the first and second fingers, and determining a diameter of the cervical os by the length of the measuring device in the extended state between the fixed attachment and slidable attachment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 14/856,472, filed Sep. 16, 2015, which claims the benefit of U.S. Provisional Application No. 62/133,897, filed Mar. 16, 2015, all of which are incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The present invention is generally related to practitioners working in labor and delivery of an infant, and more particularly, the present invention discloses methods and apparatus for consistent and accurate cervical dilation readings during labor and pregnancy. 
       BACKGROUND 
       [0003]    Every day many practitioners, such as doctors, nurses, midwives and others, assist in the labor and delivery of infants. One problem that arises is inconsistency of cervical dilation readings or measurements between different practitioners, and inconsistency within cervical dilation measurements by the same practitioner. Because of the length of labor, the same practitioner usually does not follow the entire labor course of a given patient; therefore many practitioners are involved in the management of a laboring patient, leading to discrepancies and/or inconsistencies between cervical exams (especially at shift changes). Each of the practitioners may utilize different methods and techniques to obtain cervical dilation readings or measurements. Sometimes the same practitioner may obtain different readings when checking twice. 
         [0004]    Inconsistency of cervical dilation readings may lead to problems managing labor. For example, accurate readings of progress of labor are essential because if the readings are inaccurate: 
         [0005]    The actual present stage of labor is unknown. 
         [0006]    The length of labor may be affected. 
         [0007]    Practitioners may fail to offer necessary treatments. 
         [0008]    Practitioners may recommend unnecessary treatments, including:
       Drugs   Maneuvers   Surgery       
 
         [0012]    Different practitioners use different “metrics” to estimate cervical dilation, but these tactics are not standardized and there is no testing of accuracy or precision of the measurements. Generally, a practitioner will insert two fingers into the vagina and feel the cervix. The practitioner will then estimate, by feel, the magnitude of dilation of the cervix. Therefore, the measurement is subjective. In addition, there is no consistent training provided to student practitioners (MDs/midwives/nurses) to standardize the approach. 
         [0013]    Studies have been done to determine accuracy of practitioners at determining cervical dilation. One study was designed to measure precision (variation within and between observers) and accuracy of expert cervical assessment against an objective standard using carefully constructed simulators. No examiner achieved correct assessment in every case tested. The assessment of cervical dilation was exactly right in only 175 of 360 cases (48.6%). (Tuffnel et al, Simulation of cervical changes in labour: reproducibility of expert assessment, 1989). 
         [0014]    In another study, polyvinyl chloride pipes 1 to 10 cm in diameter were mounted in cardboard boxes and used to simulate cervical examinations. The boxes were designed so that the examiner had to rely solely on proprioception to determine the inner diameter. In the results, a total of 1574 simulated cervical diameter measurements were obtained from 102 examiners in a two-part study. The overall accuracy for determining the exact diameter was 56.3% and intraobserver variability for a given diameter measurement was 52.1%. (Phelps, Accuracy and intraobserver variability of simulated cervical dilatation measurements, 1995). 
         [0015]    While the above studies used simulators, another study was done to determine accuracy in estimation of cervical dilation during the active phase of labor in vivo and to identify independent predictors of inaccuracy. Examinations were performed on 508 women. The researcher and clinicians agreed on the dilation in 250 instances (49.2%) and differed by 2 cm or more in 56 cases (11.0%). (E J Buchmann, Accuracy of cervical assessment in the active phase of labour, 2007). 
         [0016]    As is evident, practitioners differ about half the time in their measurements of cervical dilation. Inaccuracy and imprecision may negatively impact patient care related to treatment and management decisions based on cervical dilation. “Labour management is based on the assessment of the cervix. Decisions to augment labour or even carry out caesarean section are heavily influenced by the progress of labour, and assessment of progress is based on cervical dilation. Variation between observers is therefore important when care is shared and shifts change.” (Tuffnel et al, Simulation of cervical changes in labour: reproducibility of expert assessment, 1989). 
         [0017]    An incorrect cervical dilation measurement may also increase the risk of the practitioner augmenting labor, which can pose risks to both the mother and the baby. Augmenting labor increases the risk of several complications, including: 
         [0018]    Cesarean section. 
         [0019]    Fetal heart rate decelerations which indicate decreased oxygen delivery to the fetus. 
         [0020]    Post partum hemorrhage. 
         [0021]    Blood transfusion and related risks. 
         [0022]    Infection. 
         [0023]    Uterine rupture. 
         [0024]    Tools have been developed or examined to assist the practitioner in determining cervical dilation. Examples of such tools include a translabial 3-dimensional (3D) ultrasonogram, mechanical calipers, electrical displacement transducers clipped to opposite sides of the cervical rim, and a caliper-like cervimeter with leaf spring arms that coil against the outer rim of the cervix for measurement. 
         [0025]    Each of these tools was found to be unsatisfactory because they are complex, expensive, inaccurate, increase the risk of infection, may cause patient discomfort, and are difficult to integrate into clinical practice. In addition, they can: distort the cervix (introducing measurement error), cause cervical trauma, and are poorly reproducible. They are also time consuming for the practitioner and require substantial training to develop proficiency. Some protrude from the vagina, interfering with vaginal exams and increasing infection risk. 
         [0026]    “The determination of cervical dilatation is necessary in the management of labor. The rate of cervical dilatation is used to define the effectiveness of uterine contractions and the adequacy of labor. Lack of progression of cervical dilatation influences the decision to augment labor or to perform a cesarean section. Therefore it is very important that the estimate of cervical dilatation be reasonably close to the true cervical diameter when there is more than one examiner involved in the management of a laboring patient. The digital examination remains the “gold standard” for evaluation of the cervix in pregnancy; however, it has inherent variability.” (Phelps, Accuracy and intraobserver variability of simulated cervical dilatation measurements, 1995). 
         [0027]    Thus there is a need for methods and apparatus for accurate and consistent cervical dilation measurements or readings during labor for practitioners, and between different practitioners with the same patient during labor, that avoid the problems mentioned above. 
       SUMMARY 
       [0028]    The present invention generally provides improved devices, systems, and methods to accurately and precisely determine cervical dilation measurements during labor by standardization of measurements within and between practitioners. It allows for increased accuracy across all levels of training and experience and fills an important gap in practitioners&#39; ability to accurately and precisely determine cervical dilation measurements during labor. The present invention does not introduce any discomfort or risk beyond that of a routine digital vaginal examination and it fits into work flow on the labor floor without introduction of new machines or complicated technology that require advanced training. 
         [0029]    In a first aspect, embodiments of the present invention provide a cervical dilation reading apparatus. The apparatus comprises a measuring device having a length with a first portion, a second portion, and a third portion, a first attachment band configured to couple with a first finger, the first attachment band having a fixed attachment fixedly engaged with the first portion of the measuring device, and a second attachment band configured to couple with a second finger, the second attachment band having a slidable attachment slidably engaged with the measuring device along the length between the first and second portions. 
         [0030]    In another aspect, embodiments of the present invention provide a method for measuring cervical dilation providing a cervical dilation reading apparatus having a measuring device having a length with a first portion, a second portion, and a third portion, a first attachment band configured to couple with a first finger, the first attachment band having a fixed attachment fixedly engaged with the first portion of the measuring device; and a second attachment band configured to couple with a second finger, the second attachment band having a slidable attachment slidably engaged with the measuring device along the length between the first and second portions. Coupling the first attachment band to a first finger and the second attachment band to a second finger and inserting the first and second fingers into the vaginal introitus. Locating the cervix and cervical os, placing the first finger on a first side of the cervical os and extending the second finger away from the first finger to a second side, opposite the first side, of the cervical os, wherein extending the second finger away from the first finger also extends the length of the measuring device between the first and second fingers to a substantially extended state. Removing the first and second fingers and determining a diameter of the cervical os by the length of the measuring device in the substantially extended state between the fixed attachment and slidable attachment. 
         [0031]    In many embodiments, the first and second attachment bands are coupled to the first and second fingers by a force. In many embodiments, the first and second attachment bands are made of an elastic material and configured to stretch and slide over the tip or end of the first and second fingers. In many embodiments, the first and second attachment bands are open and wrap around the first and second fingers, and are then joined and secured to the fingers. In many embodiments, the first and second attachment bands are clips, tensile arcs, “finger cots”, partial gloves, glove fingers, or other configurations that can be attached to a finger. In many embodiments, the first and second attachment bands are configured to couple to the first and second fingers of a glove. 
         [0032]    In many embodiments, the slidable attachment includes a locking mechanism configured to fix or lock a length of the measuring device in a substantially extended state when the slidable attachment is slid or moved away from the fixed attachment. The substantially fixed or locked length of the measuring device may be a cervical dilation measurement. 
         [0033]    In many embodiments, the measuring device includes thin projections or collapsible arrows along the length configured to lay down or collapse as they go through the locking mechanism of the slidable attachment in a first direction when the slidable attachment is slid or moved away from the fixed attachment and then expand after going through the locking mechanism, preventing the measuring device from moving backward in a second direction, thereby locking the measuring device in the substantially extended state. 
         [0034]    In many embodiments, the measuring device includes ridges along the length configured to “pop through” an opening of the locking mechanism of the slidable attachment in a first direction when the slidable attachment is slid or moved away from the fixed attachment, the ridges being larger than the opening, such that after going through the locking mechanism, the ridges prevent the measuring device from moving backward in a second direction, thereby locking the measuring device in the substantially extended state. 
         [0035]    In many embodiments, the measuring device is configured to engage a ratcheting mechanism for locking the measuring device to the slidable attachment forming the locking mechanism, such that after going through the locking mechanism, the ratcheting mechanism prevents the measuring device from moving backward in a second direction, thereby locking the measuring device in the substantially extended state. 
         [0036]    In many embodiments, the measuring device includes material that, due to friction or pressure, resists movement through the locking mechanism of the slidable attachment, such that after going through the locking mechanism, friction or pressure between the measuring device and locking mechanism of the slidable attachment prevents the measuring device from moving, thereby locking the measuring device in the extended state. 
         [0037]    In many embodiments, the locking mechanism may allow bidirectional movement of the measuring device when the user applies forces in either direction while obtaining the cervical dilation measurement. The locking mechanism may employ any number of forces to achieve this functionality, such as pressure, friction, elastic forces, adhesives, or mechanical forces. The locking mechanism holds the measuring device in place relative to the slidable attachment when the user is not applying force to the device and prevents any sliding after the dilation measurement is obtained. This locking mechanism allows the practitioner to extend the fingers beyond the diameter of the cervix, but later pull on the third portion of the measuring device to shorten the length of the measuring device between the two fingers to equal the cervical dilation. The locking mechanism allows the device to be withdrawn without the measuring device moving relative to the slidable attachment, such that the length of the measuring device between the fixed attachment and the slidable attachment is equivalent to the cervical dilation. The locking mechanism thus applies sufficient force to the measuring device that the measuring device does not move or slide relative to the slidable attachment unless a substantial amount of force is exerted on the device. 
         [0038]    In many embodiments, the measuring device includes measurement markings along its length to measure a cervical dilation measurement. The measurement markings may be in centimeters. In many embodiments, the distance between every other centimeter is colored. In many embodiments, each centimeter is marked with a thick line. In many embodiments, the distance between every other centimeter has radiant color changes, so 0-1 cm is a first color, 1-2 cm is a second color, 2-3 is a third color, 3-4 is a fourth color, and so on with different colors. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0039]    The present embodiments may be understood from the following detailed description when read in conjunction with the accompanying figures. It is emphasized that the various features of the figures are not necessarily to scale. On the contrary, the dimensions of the various features may be arbitrarily expanded or reduced for clarity. 
           [0040]      FIG. 1  shows a cross-sectional view of the cervix, uterine body and fallopian tubes, according to the embodiments provided herein. 
           [0041]      FIGS. 2A-2E  show views looking “head-on” at the cervical face (A-A in  FIG. 1 ), according to the embodiments provided herein. 
           [0042]      FIG. 3A  is an overall view and  FIG. 3B  is a close-up view showing one embodiment of a cervical dilation reading apparatus incorporating a measuring device as part of a glove to provide accurate and reproducible readings of cervical dilation, according to the embodiments provided herein. 
           [0043]      FIG. 3C  shows one embodiment of a locking mechanism having thin projections, collapsible arrows, or barbs that compress or collapse as they go through the locking mechanism of a slidable attachment. 
           [0044]      FIG. 3D  shows another embodiment of a measuring device having ridges that “pop through” the locking mechanism of a slidable attachment. 
           [0045]      FIG. 3E  shows another embodiment of a measuring device that uses a cable tie or tie-wrap with a ratcheting mechanism for locking the measuring device on a slidable attachment. 
           [0046]      FIG. 4A  shows one embodiment of a measuring device that has color markings for the practitioner to read for dilation measurement during labor. 
           [0047]      FIG. 4B  shows another embodiment of a measuring device that has thick line markings for the practitioner to read for dilation measurement during labor. 
           [0048]      FIG. 4C  shows another embodiment of a measuring device that has radiant color change markings for the practitioner to read for dilation measurement during labor. 
           [0049]      FIG. 5A  is an overall view showing another embodiment of a cervical dilation reading apparatus incorporating a measuring device to provide accurate and reproducible readings of cervical dilation, according to the embodiments provided herein. 
           [0050]      FIG. 5B  shows one embodiment of a locking mechanism using friction or pressure that allows bidrectional movement and holds the measuring device in the extended state after the cervical dilation measurement is obtained. 
           [0051]      FIG. 5C  shows one embodiment of a locking mechanism having thin projections, collapsible arrows, or barbs that compress or collapse as they go through the locking mechanism of the slidable attachment. 
           [0052]      FIG. 5D  shows another embodiment of a measuring device having ridges that “pop through” the locking mechanism of the slidable attachment. 
           [0053]      FIG. 5E  shows another embodiment of a measuring device that uses a cable tie or tie-wrap with a ratcheting mechanism for locking the measuring device on the slidable attachment. 
       
    
    
     DETAILED DESCRIPTION 
       [0054]    Embodiments of the invention will now be described with reference to the figures, wherein like numerals reflect like elements throughout. The terminology used in the description presented herein is not intended to be interpreted in any limited or restrictive way, simply because it is being utilized in conjunction with detailed description of certain specific embodiments of the invention. Furthermore, embodiments of the invention may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the invention described herein. 
         [0055]      FIG. 1  shows a cross-sectional view of the cervix  10 , uterine body  15  and fallopian tubes  20 . The cervix  10  (or neck of the uterus) is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall. The portion projecting into the vagina is referred to as the portio vaginalis  25 . The cervix&#39;s opening is called the os  30 . The size and shape of the os and the cervix vary widely with age, hormonal state, and whether the woman has had a vaginal birth. At labor, the cervix dilates or opens to admit the infant&#39;s head. 
         [0056]    Cervical Dilation 
         [0057]      FIGS. 2A-2E  show views looking “head-on” at the cervical face  35  (A-A in  FIG. 1 ). For women who are not in labor, the cervix appears to have a small circular dimple  30  (os) at its center. This is a closed cervix. It will not admit a finger.  FIG. 2A  shows an example of a cervix that is not dilated, so the dilation measurement would be 0 centimeters (cm).  FIG. 2B  shows an example of the first stage of cervical dilation of the cervical os  30   a.    
         [0058]    As labor progresses, the cervical os  30   b  starts opening. In  FIG. 2C , the practitioner may be able to insert one finger into the cervical opening, so the dilation measurement might be considered 1 cm for most practitioners. In  FIG. 2D , the cervical opening  30   c  opens more and the practitioner may be able to insert two fingers into the cervical opening, so the dilation measurement might be considered 2 cm. 
         [0059]    Beyond 2 cm of dilation, or cervical dilation that will accommodate approximately two fingers for most practitioners, critical differences in cervical measurements between practitioners may emerge. Measurement differences between practitioners may become a critical issue for treatment during labor, as described above in the Background. 
         [0060]      FIG. 2E  shows dilation of the cervical opening that has opened between 3 cm  30   d  (left side) and 9 cm  30   e  (right side). Between 3 cm and 9 cm, there is no consistent measurement standard that practitioners use. As mentioned previously, measurement tactics are not standardized and there is no testing of accuracy or precision of the measurements. 
         [0061]    The ideal method and apparatus for use during labor for measuring cervical dilation may include one or more of the following: 
         [0062]    Maximize patient comfort. 
         [0063]    No risk of cervical trauma beyond that of a simple digital vaginal examination. 
         [0064]    Easily adapted by labor floor practitioners. 
         [0065]    Minimally invasive. 
         [0066]    Minimize risk of introducing infection. 
         [0067]    No expensive machines or technology. 
         [0068]    No cumbersome attachments to the patient that may restrict movement or comfort. 
         [0069]    Highly reproducible results/readings between practitioners and within the same practitioner (precision). 
         [0070]    Accurate readings of cervical dilation. 
         [0071]    Fits into current labor room workflow. 
         [0072]    Informs treatment and management decisions. 
         [0073]    Inexpensive/disposable. 
         [0074]    Accurate/Repeatable Measurements 
         [0075]    The disclosed invention is designed to provide highly reproducible results/readings between practitioners and within the same practitioner. 
         [0076]      FIG. 3A  is an overall view and  FIG. 3B  is a close-up view showing one embodiment of a cervical dilation reading apparatus  100  incorporating a measuring mechanism  105  as part of a sterile glove  110  to provide accurate and reproducible readings of cervical dilation. In the embodiment shown, the measuring mechanism  105  includes a measuring device  115  spanning between two adjacent fingers  120   a ,  120   b  of the glove. In other embodiments, the measuring device  115  may span more than two fingers, span non-adjacent fingers, or be incorporated into the sterile glove by other means. The measuring device  115  has a first portion  115   a  attached to a fixed or stable attachment  125  at a tip or end of the first finger, such as finger  120   a  and a second portion  115   b  coupled to a slidable attachment  130  at the tip or end of the second finger, such as finger  120   b.    
         [0077]    Slidable Attachment—In use, the practitioner would insert the first finger  120   a  and the second finger  120   b  into the cervical opening  30 . The practitioner would place the first finger  120   a  on one side of the cervical opening  30  and then move the second finger  120   b  toward the other side of the cervical opening. The first portion  115   a  of the measuring device  115  is fixed to finger  120   a  and the second portion  115   b  of the measuring device  115  slides through slidable attachment  130  of the second finger  120   b , thereby lengthening the measuring device  115  to obtain the correct dilation measurement. Once to the other side, the practitioner would then withdraw the reading apparatus  100  and read the dilation measurement from the second portion  115   b  of the measuring device  115 . 
         [0078]    Slidable Attachment Locking Mechanism—In some cases, the measuring device  115  may move or change length as it is being withdrawn after the dilation measurement, so in some embodiments the slidable attachment  130  includes a locking mechanism to fix the length of the measuring device  115  after the dilation measurement. 
         [0079]    In some embodiments, the slidable attachment  130  includes a locking mechanism that is designed to allow the measuring device  115  to slide in only one direction  135  to lengthen the measuring device  115  without any back sliding  140  after dilation measurement, such as shown in  FIG. 3B . This one-way action allows any practitioner to utilize the reading apparatus  100  and, once the measuring device  115  is locked in place, obtain the same measurement as any other practitioner would obtain with the same or similar device. The locking mechanism allows the measuring mechanism  105  to be withdrawn without the measuring device  115  moving, thereby getting the most consistent results between practitioners and maximizing patient comfort and practicality. 
         [0080]      FIGS. 3C-3E  show some embodiment examples of a locking mechanism for use with a slidable attachment.  FIG. 3C  shows one embodiment of a measuring device  115  having thin projections, collapsible arrows, or barbs  145  that compress or collapse as they go through the locking mechanism of the slidable attachment  130  in a first direction  135  when the fingers  120   a ,  120   b  are separated. The thin projections or collapsible arrows  145  then expand after going through the locking mechanism, preventing them from moving backward in a second direction  140 , thereby locking the measuring device  115  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  115  in the correct length for the dilation measurement. 
         [0081]      FIG. 3D  shows another embodiment of a measuring device  115  having ridges  150  that “pop through” the locking mechanism of slidable attachment  130  in a first direction  135  as the fingers  120   a ,  120   b  are separated. Once the ridges  150  “pop through” the locking mechanism of the slidable attachment  130 , the measuring device  115  cannot move backward in a second direction  140 , thereby locking the measuring device  115  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  115  in the correct length for the dilation measurement. 
         [0082]      FIG. 3E  shows another embodiment of a measuring device  155  that uses a cable tie or tie-wrap, also known as a hose tie, zap-strap, or zip tie with a ratcheting mechanism  160  for locking the measuring device  155  on the slidable attachment  130 . The measuring device  155  slides in a first direction  135  as the fingers  120   a ,  120   b  are separated. Once through the ratcheting mechanism  160 , the measuring device  155  can&#39;t move backward in a second direction  140 , thereby locking the measuring device  155  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  155  in the correct length for the dilation measurement. 
         [0083]    In some embodiments, the measuring device  115  includes material that, due to friction with the slidable attachment  130 , resists movement through the locking mechanism of the slidable attachment  130 , such that after going through the opening, friction prevents the measuring device  115  from moving backward in a second direction, thereby locking the measuring device  115  in the substantially extended state. 
         [0084]      1 n some embodiments, the measuring device  115  includes material that, due to pressure from the slidable attachment  130 , resists movement through the locking mechanism of the slidable attachment  130 , such that after going through the opening, pressure prevents the measuring device  115  from moving backward in a second direction, thereby locking the measuring device  115  in the substantially extended state. 
         [0085]    In some embodiments, the practitioner needs to be able to move fingers around at will while searching for the edges of the cervix without worrying about overshooting the measurement. In this case, the locking mechanism may be configured to allow sliding or movement of the device in a second direction through the slidable attachment when force is applied to the measuring device in a second direction. This allows the practitioner to tighten it back up by pulling on the measuring device. 
         [0086]    Measuring Mechanism—The measuring device  155  of the measuring mechanism  105  is used to measure dilation of the cervical opening as labor progresses and can be made of any pliable material that would be suitable for measurement purposes. In the embodiments shown, the measuring device is a string having markings to measure dilation, preferably in centimeters, but other measurement units may be used. Different measuring mechanisms could be used to make the determination of measuring device  115  length, some examples are described below. If no markings are utilized on the measuring device  115 , the length of the measuring device  115  can be compared to a ruler by the practitioner to determine the length after the measurement is complete. 
         [0087]      FIGS. 4A-4C  show some embodiment examples of measuring devices that have markings to measure the dilation measurement during labor. This system makes it fast and easy, with consistent results, for the practitioners to use the measuring device to measure dilation. While the embodiments below will be described with a string, other suitable materials may be used. 
         [0088]      FIG. 4A  shows one embodiment of a string  200  with markings in centimeters  205 , where the distance between every other centimeter is colored, so 0-1 cm is a first color  210   a , 1-2 cm is a second color  210   b , and so on, with the colors repeating. Once the practitioner has withdrawn the reading apparatus  100  from the cervical opening, the practitioner then uses the section and/or color on the string  200  to determine the dilation measurement proximate the slidable attachment  130 . 
         [0089]      FIG. 4B  shows another embodiment of a string  220  with markings in centimeters  205 , where every centimeter has a thick line  225  that is easy for the practitioner to read (like a ruler). Once the practitioner has withdrawn the reading apparatus  100  from the cervical opening, the practitioner then uses the thick line  225  on the string  220  to determine the dilation measurement proximate the slidable attachment  130 . 
         [0090]      FIG. 4C  shows one embodiment of a string  230  with markings in centimeters  205 , where the distance between every other centimeter has radiant color changes, so 0-1 cm is a first color  235   a , 1-2 cm is a second color  235   b , 2-3 is a third color  235   c , 3-4 is a fourth color  235   d , and so on with different colors. Once the practitioner has withdrawn the reading apparatus  100  from the cervical opening, the practitioner then uses the color on the string  230  to determine the dilation measurement proximate the slidable attachment  130 . 
         [0091]    Steps For Use
       1. Proper consent is obtained and the patient is appropriately prepared for a digital vaginal examination.   2. Practitioner puts the glove on in a sterile fashion.   3. According to practitioner and patient preference, the practitioner may apply sterile lubricant to fingers to be used in the examination, for example, the pointer (or 2nd finger) and middle (or 3rd finger). This is optional and used routinely in obstetric practice to increase patient comfort with digital vaginal examination. Lubricant has no effect on the device or measurement.   4. Practitioner inserts  2   nd  and 3 rd  fingers into the vaginal introitus. The practitioner finds the cervix and places the 2 nd  finger stationary at the patient&#39;s right side of the cervical os (or left side if the practitioner is left-handed). The practitioner extends the 3 rd  finger to the opposite side of the cervical os, extending the string. Care is taken not to stretch, distort or injure the cervix. Throughout use, the retention mechanism, if present, retains the measuring device in close proximity to the rest of the device.   5. The practitioner ensures that the measuring device is taught between the two fingers and then engages the locking mechanism, if one is present, while the measuring device is in the fully extended state equal to the diameter of the cervical opening.   6. The practitioner now begins to remove his/her hand, allowing the two fingers to close to prevent patient discomfort.   7. Once the hand is removed, the practitioner carefully extends the 2 nd  and 3 rd  finger without further sliding at the locking mechanism. The practitioner can use the length of the measuring device between the two fingers to determine the diameter of the cervical os.   8. The measurement of the cervical dilation is recorded.   9. The glove/device is disposed of       
 
         [0101]    Finger Attachment 
         [0102]      FIG. 5A  is an overall view and  FIG. 5B  is a close-up view showing an embodiment of a cervical dilation reading apparatus  300  incorporating a measuring device  315  configured to provide accurate and reproducible readings of cervical dilation. 
         [0103]    In the embodiment shown, the cervical dilation reading apparatus  300  includes a first attachment band  306  that can be attached to a first finger  120   a  and a second attachment band  307  that can be attached to a second finger  120   b . A measuring device  315  is coupled to the first and second attachment bands  306 ,  307  spanning between the two fingers  120   a ,  120   b . The measuring device  315  includes measurement markings and other features of similar measuring devices described above. The first and second attachment bands  306 ,  307  may be used without a glove, or paired with a glove  110 . In other embodiments, the cervical dilation reading apparatus  300  may span more than two fingers, span non-adjacent fingers, or be incorporated into or attached to a sterile glove by other means. The measuring device  315  has a first portion  315   a  fixedly coupled to the first attachment band  306  by a fixed attachment  325 , a second portion  315   b  slidably coupled to the second attachment band  307  by a slidable attachment  330 , and a third portion  315   c  beyond the slidable attachment  330 . The first attachment band  306  may be positioned on the first finger  120   a  proximate a tip or end, and the second attachment band  307  may be positioned on the second finger  120   b  proximate a tip or end. 
         [0104]    The first and second attachment bands  306 ,  307  are designed to be held in place on the fingers by a force, such as friction, tension, adhesives, pressure, mechanical forces, or other mechanisms that will be apparent to one skilled in the art. The bands may be made of an elastic material, similar to a rubber band, silicone band, or plastic band, so that the attachment bands stretch and slide over the finger tips, but remain in place once the user positions them on the fingers. In other embodiments, the bands are made of an inelastic material, an adhesive material, or other materials that will be apparent to one skilled in the art. In other embodiments, the first attachment band  306  and second attachment band  307  may open at the end and wrap around the fingers, with the ends joined and secured with tape, Velcro, tie, or other suitable attachment means. In other embodiments, the attachment bands  306 ,  307  may be clips, tensile arcs, “finger cots”, partial gloves, glove fingers, or other configurations that can be attached to a finger that will be apparent to one skilled in the art. 
         [0105]    Locking Mechanism 
         [0106]    The measuring device  315  may move or change length as it is being withdrawn from the vagina after the dilation measurement, so some embodiments include a locking mechanism designed to allow the measuring device  315  to slide in direction  135  as the fingers are spread for dilation measurement and lock the measuring device  315 . In some embodiments, the locking mechanism may allow bidirectional movement when the user applies forces in either direction  135  or  140  while obtaining the cervical dilation measurement. The locking mechanism locks the slidable attachment in place when the user is not applying force to the device and prevents any sliding after dilation measurement is completed, such as shown in  FIG. 5B . This locking action allows any practitioner to utilize the cervical dilation reading apparatus  300  and, once the measuring device  315  is locked in place, obtain the same measurement as any other practitioner would obtain with the same or similar device. The locking mechanism allows the cervical dilation reading apparatus  300  to be withdrawn without the measuring device  315  moving, thereby getting the most consistent results between practitioners and maximizing patient comfort and practicality. 
         [0107]      FIG. 5B  shows one embodiment of the cervical dilation reading apparatus  300  with a measuring device  315  made of a string or other flexible material that has a fixed attachment  325  to the first attachment band  306  and a slidable attachment  330  to the second attachment band  307 . The measuring device  315  slides through the second attachment band  307  in a first direction  135  when the fingers  120   a ,  120   b  are separated. The user may apply force to the third portion of the measuring device  315   c  to slide the measuring device  315  through the second attachment band  307  in the second direction  140 . Once the measurement is obtained, forces between the second portion of the measuring device  315   b  and the locking mechanism of the slidable attachment  330  prevent the measuring device  315  from sliding in either direction  135  or  140 , thereby locking the measuring device  315  in the extended state after obtaining the dilation measurement. Forces between the measuring device  315  and the locking mechanism of the slidable attachment  330  may include tension, friction, compression, resistance, mechanical forces, spring forces, adhesives, or other forces that will be apparent to one skilled in the art. This will then lock the measuring device  315  in the correct length for the dilation measurement. 
         [0108]      FIGS. 5C-5E  show some embodiment examples of a locking mechanism for use with a slidable attachment.  FIG. 5C  shows one embodiment of the cervical dilation reading apparatus  300  with a measuring device  315  having thin projections, collapsible arrows, or barbs  345  that compress or collapse as they go through the locking mechanism of the slidable attachment  330  in a first direction  135  when the fingers  120   a ,  120   b  are separated. The thin projections or collapsible arrows  345  then expand after going through the locking mechanism, preventing them from moving backward in a second direction  140 , thereby locking the measuring device  315  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  315  in the correct length for the dilation measurement. 
         [0109]      FIG. 5D  shows another embodiment of the cervical dilation reading apparatus  300  with a measuring device  315  having thin ridges  350  that “pop through” the locking mechanism of slidable attachment  330  in a first direction  135  as the fingers  120   a ,  120   b  are separated. Once the ridges  350  “pop through” the locking mechanism, the measuring device  315  cannot move backward in a second direction  140 , thereby locking the measuring device  315  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  315  in the correct length for the dilation measurement. 
         [0110]      FIG. 5E  shows another embodiment of the cervical dilation reading apparatus  300  with a measuring device  355  that uses a cable tie or tie-wrap, also known as a hose tie, zap-strap, or zip tie with a ratcheting mechanism  360  for locking the measuring device  355  on the slidable attachment on the second attachment band  307 . The measuring device  355  slides in a first direction  135  as the fingers  120   a ,  120   b  are separated. Once through the ratcheting mechanism  360 , the measuring device  355  can&#39;t move backward in a second direction  140 , thereby locking the measuring device  355  in the substantially extended state after measuring the dilation measurement. This will then lock the measuring device  355  in the correct length for the dilation measurement. 
         [0111]    In use, the practitioner would insert the first finger  120   a  and the second finger  120   b  and the cervical dilation reading apparatus  300  with measuring device  315  into the cervical opening  30 . The practitioner would place the first finger  120   a  on one side of the cervical opening  30  and then move the second finger  120   b  toward the opposite side of the cervical opening. The first portion  315   a  of the measuring device  315  is fixed to the first attachment band  306  which is coupled to the first finger  120   a  and the second portion  315   b  of the measuring device  315  slides through the slidable attachment  330  of the second attachment band  307  which is coupled to the second finger  120   b , thereby lengthening the measuring device  315  to obtain the correct dilation measurement. Once to the other side, the practitioner would then withdraw the cervical device reading apparatus  300 , and read the dilation measurement from the second portion  315   b  of the measuring device  315 . 
         [0112]    If during the cervical examination, the practitioner stretches the fingers  120   a ,  120   b  beyond the diameter of the cervical opening  30 , the practitioner may subsequently close the fingers  120   a ,  120   b  to place them on opposite sides of the cervical opening  30 . The practitioner may then apply force to the third portion of the measuring device  315   c  to shorten the length of the measuring device between fingers  120   a  and  120   b , resulting in a length between the first finger  120   a  and the second finger  120   b  equivalent to the diameter of the cervical opening  30 . The practitioner would then withdraw the cervical dilation reading apparatus  300 , and read the dilation measurement from the second portion  315   b  of the measuring device  315 . 
         [0113]    Similarly, the practitioner may extend the fingers  120   a ,  120   b  beyond the diameter of the cervical os  30  when donning the apparatus, when adjusting the apparatus on the fingers, when initiating the cervical examination, or during the cervical examination. If overextension occurs at any point, the practitioner may shorten the length of the measuring device  315  between the two bands  306  and  307  by pulling on the third portion of the measuring device  315   c.    
         [0114]    After obtaining the cervical dilation measurement, the practitioner may close his/her fingers  120   a ,  120   b  prior to removing his/her fingers  120   a ,  120   b  and the cervical dilation reading apparatus  300  from the vagina. The locking mechanism will hold the second portion  315   b  of the measuring mechanism  315  in place, allowing the practitioner to read the correct cervical dilation measurement from the second portion  315   b  of the measuring mechanism  315 . 
         [0115]    Steps For Use
       1. Proper consent is obtained and the patient is appropriately prepared for a digital vaginal examination.   2. Practitioner positions the first attachment band on a first finger and the second attachment band on a second finger.   3. According to practitioner and patient preference, the practitioner may apply lubricant to fingers to be used in the examination, for example, the pointer (or 2nd finger) and middle (or 3rd finger). This is optional and used routinely in obstetric practice to increase patient comfort with digital vaginal examination. Lubricant has no effect on the device or measurement.   4. Practitioner inserts 2 nd  and 3 rd  fingers into the vaginal introitus. The practitioner finds the cervix and places the 2 nd  finger stationary at one edge of the cervical os. The practitioner extends the 3 rd  finger to the opposite side of the cervical os, extending the measuring device. Care is taken not to stretch, distort or injure the cervix. If the practitioner stretches the fingers beyond the diameter of the cervical os, he/she can subsequently place the fingers on opposite sides of the cervical os and pull on the third portion of the measuring device to shorten the length of measuring device between the examining fingers so that it is equal to the diameter of the cervical os.   5. The locking mechanism locks the measuring device in the extended state equal to the diameter of the cervical opening.   6. The practitioner now begins to remove his/her hand, allowing the two fingers to close to prevent patient discomfort.   7. Once the hand is removed, the practitioner can use the length of the measuring device between the two fingers to determine the cervical dilation.   8. The measurement of the cervical dilation is recorded.   9. The first and second attachment band are removed from the fingers.       
 
         [0125]    The disclosed invention fills an important gap in practitioners&#39; ability to accurately and precisely determine cervical dilation measurements during labor. 
         [0126]    It provides standardization of measurements within and between practitioners. 
         [0127]    It does not introduce any discomfort or risk beyond that of a routine digital vaginal examination. 
         [0128]    It fits into work flow on the labor floor without introduction of new machines or complicated technology that require advanced training. 
         [0129]    It allows for increased accuracy across all levels of training and experience. 
         [0130]    Currently, no device or technology exists to fill this gap in practitioners&#39; clinical ability/practice. 
         [0131]    No device of this nature has ever been described or introduced. 
         [0132]    As such, this device presents a novel and important addition to medicine. 
         [0133]    While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications than mentioned above are possible without departing from the inventive concepts herein. It is to be understood that the present disclosure is illustrative only and that changes, variations, substitutions, modifications and equivalents will be readily apparent to one skilled in the art and that such may be made without departing from the spirit of the invention as defined by the following claims.