Abstract:
An intrauterine balloon apparatus to augment uterine birthing forces and assist fetal descent during parturition is provided. The body of the balloon apparatus begins packaged in a compressed state minimizing volume, enabling delivery through the birth canal. The apparatus is advanced to a proximal uterine location and deployed for operation by introducing a pressurized agent through its conduit, causing the body to expand and apply directional forces towards the infant and birth canal. The balloon body is shaped to apply pressures dispersed towards the infant and the bidirectional conduit enables fluid conduction as the infant descends. After the infant has successfully descended and been delivered through the birth canal, pressure within the balloon body is relieved through the conduit thereby collapsing the volume of the balloon body and enabling refraction through the birth canal.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 62/080,511, entitled “Intracorporeal Birthing Device” and filed on Nov. 17, 2014, and U.S. Provisional Application Ser. No. 62/080,506, entitled “Birthing Assistance Catheter” and filed on Nov. 17, 2014, each of which is expressly incorporated by reference herein in its entirety. 
         [0002]    This application includes subject matter related to co-pending U.S. patent application Ser. No. 14/942,577, entitled “Intrauterine Access Catheter for Delivering and Facilitating Operation of a Medical Apparatus for Assisting Parturition,” and filed on Nov. 16, 2015, which is expressly incorporated by reference herein in its entirety. 
     
    
     BACKGROUND 
       [0003]    1. Field 
         [0004]    The present disclosure relates generally to the field of obstetrics, and more specifically, to a medical balloon apparatus and system for assisting infant descent during parturition. The apparatus or system can be used during any stage for a full term pregnancy, and is particularly useful when insufficient uterine contractile effectiveness is diagnosed resulting in infant descent latency (i.e. dystocia, or the “failure to descend”) and when coordinated mechanical assistance to aid infant descent is desired. 
         [0005]    2. Background 
         [0006]    There are three physiologic stages of labor during the intrapartum process of natural childbirth. The first stage is latent labor and begins when the uterine muscles begin to tighten (contract) and relax in a periodic manner. These early contractions occur at an irregular frequency each lasting for less than a minute and are known to be uncomfortable for the mother. The total duration of this first phase is highly variable and last from several hours to several days. Over time frequency of the contractions becomes more regular and grows with intensity, resulting in increased intrauterine pressures and associated pain, causing greater downward forces towards the infant and birth canal leading to the thinning (effacing) and opening (dilation) of the cervix. 
         [0007]    The second stage is active labor and begins when the mother&#39;s uterine contractions become more regular and frequent, generating sufficient coordinated strength towards the infant and birth canal causing the cervix to become thinner and diameter to grow larger for the infant to begin descending down the birth canal. The combination of intensifying uterine contractions, increased intrauterine pressures, and reduced birth canal resistance promotes gradual infant descent through the birth canal until it is eventually delivered or surgically extracted. The duration of this stage lasts several hours and is associated with active infant movement and significant maternal pain. The third stage follows the delivery of the infant after which uterine contractions and the intrapartum process continues resulting in the expulsion of the placenta. 
         [0008]    Difficulties often arise during the first and second stage when the mother&#39;s uterus is unable to generate the required contractility to initiate and ensure steady progression of the infant down the birth canal. Furthermore, increased resistance to infant descent by the mother&#39;s pelvic region along the birth or cervical canal requires greater effective birthing forces to ensure infant descent. A significant percentage of women therefore experience prolonged durations of labor which subsequently extends morbidity and increases the risks to both her and her infant due to extended physical stress. 
         [0009]    A significant clinical need exists to manage intrauterine birthing forces for the purposes of assisting, stabilizing, or accelerating the birthing process during the first and second stage of labor. Currently, when a mother experiences prolonged durations of labor, the mainstay pharmacologic intervention used is synthetic Oxytocin (Pitocin) for stimulating and increasing uterine contractions. Dosages are based on protocols derived from a combination of population data and individual patient assessments of contraction rates and birthing progress, but individual patient&#39;s intrauterine pressures are generally not optimized on a per case basis. Although a very small minority of patients do receive intrauterine pressure monitors for titrating titrating Oxytocin, labor management using individual pressure optimization is not widely accepted due in large part to data suggesting pharmacologic interventions are limited with their effectiveness to achieve sufficient pressures. Other methods of assisting the birthing process include prostaglandins and Pessary cervical dilators to reduce the resistance of the birth canal to infant descent but do not compensate for ineffective uterine contractions. 
         [0010]    In totality these interventions prove to be only marginally effective, and a significant percentage of mothers attempting natural births eventually undergo a surgical extraction of the infant (Cesarean) through a transverse abdominal incision to directly access the uterine cavity. Because Cesarean surgical interventions are highly invasive and result in extensive maternal morbidity, an increase of recovery times, and significantly greater risks of uterine injury with future subsequent births, a clinical need exists for providing an alternative option in lieu of a Cesarean section intervention by safely enhancing uterine descent forces and reducing labor durations. 
       SUMMARY 
       [0011]    Disclosed herein is an intrauterine medical balloon apparatus, system, and method for obstetric applications to assist infant descent through the birth canal during parturition by augmenting uterine birthing forces. The apparatus applies forces towards the infant and birth canal to augment the effectiveness of natural physiologic uterine contractions. The apparatus is placed in a proximal uterine location to the infant and birth canal. A pressurized agent is introduced into the apparatus causing the apparatus to expand and apply directional pressure dispersed towards the infant. The medical balloon apparatus may be used during any stage of active labor, but particularly when one or more pathological periods of latency is diagnosed (dystocia, or the “failure to descend”) or pathological uterine contractile effectiveness is diagnosed during the first or second stage of labor and sufficient cervical dilation has occurred. 
         [0012]    In one aspect, a medical balloon apparatus includes a conduit body having a proximal region, a distal region, and an internal lumen. The medical balloon apparatus also includes a balloon body coupled to the distal region of the conduit. The balloon body has an internal chamber in fluid communication with the internal lumen of the conduit. The balloon body is configured to be placed in an intrauterine cavity at a location between an infant and uterine walls, and is further configured to operate, e.g., transition between a compacted state and an expanded state, there from. When in the expanded state the balloon body applies a force to a base of the infant in the direction of the cervical canal. 
         [0013]    In another aspect, a medical balloon apparatus is configured to transition between a collapsed state and an expanded state. The medical balloon apparatus includes a conduit body having a proximal region, a distal region, and an internal lumen, and a balloon body coupled to the distal region of the conduit. The balloon body has an internal chamber in fluid communication with the internal lumen of the conduit, and includes a first wall and a second wall opposite the first wall. The balloon body is configured to expand to a shape wherein: the balloon body comprises an axis passing through the first wall and the second wall; during expansion of the balloon body, the first wall is displaced relative to the axis in a first direction, and the second wall is displaced relative to the axis in a second direction opposite the first direction; and the degree of displacement of the first wall is greater than the degree of displacement of the second wall. 
         [0014]    In yet another aspect, a medical balloon apparatus is configured to fit at least partially within a lumen of an access catheter and to be deploy by sliding within the lumen. The medical balloon apparatus includes a balloon body having an internal chamber. The balloon body is configured to transition from a contracted state having a volume less than 10 ml and an external diameter less than 24 Fr (or 8mm), to an expanded state upon introduction of a pressurized agent into the internal chamber. The balloon body has an exterior surface constructed with a low friction smooth bio compatible material with a coefficient of friction of less than 0.1 against the lumen of the access catheter. 
         [0015]    In another aspect, a method of augmenting expulsive uterine forces towards a cervical canal during delivery of a fetus from a uterus, includes monitoring an intrinsic uterine contraction. The method further includes mediating a force generated via a medical balloon apparatus having a balloon body located in the uterus during the intrinsic uterine contraction. The force is directed toward the cervical canal and augments natural expulsive uterine forces, and mediating the force may include delivering pressurized agent to the balloon body to increase the force, or discharging agent from the balloon body to decrease the force. 
         [0016]    In still another aspect, a system for augmenting expulsive uterine forces towards a cervical canal during delivery of a fetus from a uterus includes a medical balloon apparatus having a balloon body configured to be positioned in the uterus. The system also includes a controller coupled to the medical balloon apparatus and configured to monitor an intrinsic uterine contraction; and mediate a force generated via the balloon body during the intrinsic uterine contraction, wherein the force is directed toward the cervical canal and augments natural expulsive uterine forces. The controller may mediate the force by delivering pressurized agent to the balloon body to increase the force, or discharging agent from the balloon body to decrease the force. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is an illustration of a medical balloon system including a controller and a medical balloon apparatus in a collapsed, pre-deployed state. 
           [0018]      FIG. 2  is cross section illustration of a medical balloon apparatus positioned within a delivery catheter. 
           [0019]      FIG. 3  is a cross section illustration of the medical balloon apparatus of  FIG. 1 . 
           [0020]      FIG. 4  is a cross section illustration of the medical balloon apparatus of  FIG. 1  in an expanded, deployed state, including a balloon body of a first configuration. 
           [0021]      FIGS. 5A-5C  are schematic illustrations of a balloon body at different stages of expansion. 
           [0022]      FIG. 6  is a cross section illustration of the medical balloon apparatus of  FIG. 1  in an expanded, deployed state, including a balloon body of an alternate configuration. 
           [0023]      FIG. 7  is an illustration of the medical balloon apparatus of  FIG. 1  positioned in an intrauterine cavity, in a collapsed, pre-deployed state. 
           [0024]      FIG. 8  is an illustration of the medical balloon apparatus of  FIG. 1  positioned in an intrauterine cavity, in an expanded, deployed state. 
           [0025]      FIG. 9  is a flow chart of a method of augmenting expulsive uterine forces towards a cervical canal during delivery of a fetus from a uterus. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts. 
         [0027]    Disclosed herein is an intrauterine medical balloon apparatus, system, and method to assist parturition. The objective of the apparatus, system, and method is to assist infant descent through the birth canal within the uterine cavity by augmenting intrinsic uterine birthing forces. The medical balloon apparatus includes a conduit body and a balloon body in fluid communication with each other. In use, the medical balloon apparatus is placed at an intrauterine location proximal to the infant and the birth canal, which may also be referred to as the cervical canal. Pressurized gas or fluid agent is conducted through the conduit body and into the balloon body causing the balloon body to expand. The balloon body is constructed so that a facet of the balloon body comes into contact with the infant during expansion of the balloon and applies pressure towards the base of the infant and towards the birth canal, thereby augmenting intrinsic uterine contraction forces and assisting infant descent through the birth canal. 
         [0028]    In a configuration, the medical balloon apparatus is compatible for use with a catheter to access the uterine cavity via the cervix and navigate the infant, placenta, umbilical cord, and other intrauterine structures to the region of the fundus near the proximal end of the uterine cavity between the infant and endometrium lining. After reaching the target location, with the body of the balloon apparatus inline with the infant and birth canal at a proximal uterine location, a facet of the balloon body is placed adjacent the base of the infant. A pressurized gas or fluid agent is introduced into the proximal end of the conduit and conducted along the length of the conduit into the balloon body. The pressurized delivery of the agent can be timed in a synchronous manner to intrinsic uterine contractions resulting in expansion of the balloon body and application of forces towards the base of the infant and birth canal in-phase with natural maternal birthing forces. In one configuration, the conduit body conducts intra-balloon agent to a pressure sensor associated with the conduit body, e.g., at the distal end region of the conduit body. The conduit body may be attached to an external control unit and pressure signals obtained by the sensor may be provided to the control unit. The information on balloon pressure may be processed by the control unit to monitor intrauterine pressure and to time the delivery of the pressurized agent into the balloon body through the conduit so that the balloon body expands during intrinsic contractions and collapses in the absence of an intrinsic contraction. In an alternative configuration, the delivery of the pressurized agent is synchronized to an external measure of muscular activity caused by uterine contractions. 
         [0029]    The proximal uterine cavity where the balloon body is placed, which may be defined by the space between the proximal uterine walls and the infant, expands as the infant descends. The balloon body is configured to expand correspondingly in both size and shape in order to proportionately fill the ongoing changes to the proximal uterine cavity shape, and augment the intrinsic pressure applied towards the infant and birth canal, while being further configured to limit the expansion of the balloon body against the surrounding uterine structures and uterine walls. The balloon body continues to expand until the infant is delivered or removed by a birthing professional. 
         [0030]    Following successful vaginal delivery of the infant, the balloon body is deflated and the medical balloon apparatus is retracted through the birth canal and removed. The medical balloon apparatus can optionally be inflated and left in place to control excessive blood loss immediately following removal of the placenta. 
         [0031]      FIG. 1  is an illustration of a medical balloon system  100  including a controller  104  and a medical balloon apparatus  102  in a collapsed, pre-deployed state. The medical balloon apparatus  102  includes a conduit body  106  having a proximal region  108  and a distal region  110 . The medical balloon apparatus  102  also includes a balloon body  112  coupled to the distal region  110  of the conduit body  106 , a coupling adapter or connector  114  at the proximal region  108  of the conduit body, and a relief valve  116 . The relief valve  116  may be associated with the conduit body  106  in the proximal end region thereof, or may be integrated with the connector  114 . The relief valve  116  may be configured to open automatically when pressure in the valve exceeds a threshold value. The relief valve  116  may also be configured to operate under control of an electrical signal, wherein the valve may be fully or partially opened and then closed in order to obtain or maintain a target internal pressure inside the medical balloon apparatus  102 . 
         [0032]    The conduit body  106  defines a hermetically sealed internal lumen  126  that traverses the length of the conduit body and is in sealed communication with the internal space of the balloon body  112 . The conduit body  106  may be formed of high density polyethylene (HDPE), polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyester, polyether block amide (PEBA), polyurethane, polyimide, polyolefin, or nylon; and in one configuration has a length of at least 30 centimeters (cm). The connector  114  is configured to connect the medical balloon apparatus  102  to the controller  104  and provide an interface between the internal lumen  126  of the conduit body  106  and an agent source, such as a fluid/gas source  118 , associated with the controller. The fluid/gas source  118  may be associated with the controller  104  through a pump  122 , which may operate under control of the controller  104 . The conduit body  106  enables bidirectional agent conduction between the agent source  118  and balloon body  112  through the internal lumen  126 . 
         [0033]    In operation, a pressurized agent, such as a gas or fluid agent  124  is delivered from the agent source  118 , through the pump  122 , into the controller  104 , and then through the connector  114 , into an internal lumen  126  defined by the conduit body  106 . As previously described, the relief valve  116  may be located at the proximal end region of the conduit body  106 , e.g., within the first 10 cm of the proximal region, or may be integrated with the connector  114 . In either case, the relief valve  116  includes a deflectable member  128  that is configured by a pre-set resistance to deflect and thereby provide an opening through which gas or fluid agent  124  may be released from the internal lumen  126  into the ambient environment. Deflection of the deflectable member  128  may occur when the pressure within the internal lumen  126  exceeds a maximum pressure threshold. For example, the pressure threshold may be between 50-200 mmhg. In this sense, the relief valve  116  may function as an emergency relief valve that automatically releases agent from the balloon body  112  through the internal lumen  126  to thereby prevent over inflation of the balloon body. 
         [0034]    As described further below with reference to  FIG. 7  and  FIG. 8 , the medical balloon apparatus  102  operates within an intrauterine cavity to augment forces towards an infant during labor. To this end, the medical balloon apparatus  102  is configured to transition from the collapsed, pre-deployed state of  FIG. 1 , to an expanded or deployed state. While in a pre-deployed state, the medical balloon apparatus  102  may be delivered through the cervical canal so as to place the balloon body  112  in an intrauterine cavity, which may be defined by the space between an infant and uterine walls. To affect such delivery, the balloon body  112  may be contained within a compacted packaged format wherein the balloon body has an internal volume of less than 10 ml and an outer diameter  120  of less than 24 French (8 mm). In the expanded state, the balloon body  112  may assume a shaped that fits within the intrauterine cavity, and a size having a volume between 150 ml and 3000 ml and a maximum diameter between 5 cm and 20 cm. The balloon body  112  may be constructed from soft pliable biocompatible materials including one or more of silicone, polyurethane, polyvinyl chloride, latex, or mylar. 
         [0035]    Transition of the balloon body  112  between a compacted state and an expanded state, and between different levels of expansion, may be controlled by the controller  104  based on one or more measures indicative of the state of intrinsic uterine contractions. The one or more measures may correspond to pressure measurements or electrical morphology measurements, and the intrinsic uterine contraction states represented by these measurements may include: a contraction onset, an increasing contraction stage during which contraction forces have increased, and a decreasing contraction stage during which contraction forces have decreased. 
         [0036]    With respect to pressure measurements, the medical balloon apparatus  102  may include a pressure sensor that senses pressure within either the internal lumen  126  or the balloon body  112  and outputs an electrical signal corresponding to the measured pressure. Each of the pressure sensor and the relief valve  116  may be electrically coupled to an electrical contact of the connector  114 . The controller  104  may be configured to receive a signal from the pressure sensor, process the received signal to obtain a corresponding pressure measurement, compare the pressure measurement to a threshold or target value, and output a control signal to the relief valve  116 . In this case, as described above, the relief valve  116  may be configured to open and close under the control of the control signal from the controller  104 . 
         [0037]    Initially, the controller  104  may monitor pressure signals to detect for an onset of an intrinsic uterine contraction. To this end, upon delivery of the balloon body  112  to the intrauterine cavity, the controller  104  may deliver agent to the balloon body to partially expand the balloon body to facilitate pressure measurements by the pressure sensor associated with the conduit body  106 . Thereafter, the controller  104  may compare measured pressures to a pressure value indicative of contraction onset. If a measured pressure exceeds the onset pressure value, the controller  104  may determine that a contraction onset has been detected and may deliver additional agent to the balloon body  112  to further expand the balloon body. An example onset pressure value may be a pressure greater than 0 mmhg, with typical pressure ranges of between 0-30 mmhg during initial stages of labor. During progressive labor, the pressures may increase up to 60-80 mmhg. 
         [0038]    After detection of a contraction onset and initial expansion of the balloon body  112 , the controller  104  may monitor the pressure signals and may mediate the delivery and discharge of fluid/gas to and from the balloon body based on such monitoring. For example, the controller  104  may control the relief valve  116  such that the relief valve discharges fluid/gas from the balloon body  112  when the sensed pressure exceeds the threshold value, such as 200 mmhg. 
         [0039]    The controller  104  may also be configured to control the delivery of agent to the balloon body  112  and the discharge of agent from the balloon body such that expansion and contraction of the balloon body is synchronized to measured pressures. In this regard, the measured pressures are considered to relate to intrinsic uterine contractions, wherein an increase in a measured pressure indicates an increase in intrinsic contraction forces, while a decrease in measured pressure indicates a decrease in intrinsic contraction forces. Pressurized agent delivery is synchronized with intrinsic uterine contractions in order to augment with additive, versus subtractive, descent infant forces, and occurs in phase with other peripheral effects associated with effective uterine contractions during intrinsic contractions. These peripheral effects include secondary muscle recruitment and cervical dilatory responses to direct descent forces and reduce resistance to infant descent. 
         [0040]    To affect synchronization of the expansion and contraction of the balloon body  112  to the measured pressure, the controller  104  may increase the delivery of agent in response to an increase in the measured pressure. The delivery of agent increases the expansion of the balloon body  112  and thereby augments the intrinsic uterine contraction forces. Conversely, the controller  104  may discharge agent in response to a decrease in the measured pressure. The discharge of agent results in contraction of the balloon body  112  and a corresponding reduction in the augmentative forces applied by the balloon. Controlling expansion and contraction of the balloon body  112  enables controlling the degree of excursions taken by the balloon wall towards the infant and birth canal per intrinsic uterine contraction, thereby limiting the rate of infant descent to clinically desired rates. The amount or degree by which forces provided by the balloon body  112  are either increased or decreased may be a function of the measured pressures. 
         [0041]    To this end, the controller  104  may be programmed to monitor the measured pressures and to detect an intrinsic change in measured pressure that exceeds a threshold amount. An intrinsic change corresponds to a change that results from intrinsic uterine contraction activity. The change may be either an increase in pressure or a decrease in pressure. Upon detection of a change in pressure that satisfies the threshold criterion, the controller  104  may deliver or discharge a predetermined amount of agent in order to affect a further change in pressure. 
         [0042]    For example, with respect to increasing pressure due to intrinsic uterine contraction activity, if the threshold pressure is P and the controller  104  detects an increase in intrinsic measured pressure that exceeds P, the controller may increase delivery of agent in order to cause the measured pressure to increase by a proportional amount of P, such as 10% of P, to obtain a current measured pressure P C =P+0.10 P. The proportional increase in pressure causes the balloon body  112  to expand and augment the intrinsic uterine forces. The controller  104  may then monitor for further intrinsic increases in the measured pressure that satisfy a criterion and respond accordingly by delivering additional agent to further augment the increasing intrinsic uterine forces. The criterion may be a subsequent measured pressure that exceeds the current measured pressure P C  by a threshold amount. The controller  104  may also incrementally and periodically increase the pressure within the balloon body  112  during a period of time that the measured pressure remains substantially constant, i.e., changes in measured pressures do not exceed the threshold. These incremental increases further augment the intrinsic uterine forces. 
         [0043]    With respect to decreasing pressure due to intrinsic uterine contraction activity, the controller  104  may detect a decrease in intrinsic measured pressure that falls below a current measured pressure P C  by a threshold amount. In this case, the controller  104  may discharge agent from the balloon body  112  in order to cause the measured pressure to decrease by a proportional amount of the current measured pressure P C , such as 10% of P C . The proportional decrease in pressure causes the balloon body  112  to contract in synchrony with the intrinsic uterine forces. The controller  104  may then monitor for further intrinsic decreases in measured pressure that satisfy a criterion and response accordingly by discharging additional agent from the balloon body  112 . 
         [0044]    One or more walls of the balloon body provide constructive augmentative forces towards the infant in phase with intrinsic uterine contractions, by pressurized delivery of agent through the conduit resulting in inflation and deflation of the balloon body in phase with intrinsic uterine contractile forces. The augmentative application of pressure thereby results in a similar intrauterine pressure morphology as the labor contractions caused by natural, unaided intrinsic physiologic uterine contractions. 
         [0045]    With respect to electrical morphology signals that are indicative of the state of intrinsic uterine contractions, the controller  104  may receive electrical signals from an electrical sensor configured to monitor uterine muscular contractions. The electrical sensor may be part of the medical balloon apparatus  102  or may be an external sensor independent of the medical balloon apparatus that is directly connected to the controller  104 . For example, electrical sensors may be located on a catheter that delivers the medical balloon apparatus. The controller  104  may be programmed to analyze the morphology of the electrical signals, to determine a contraction onset, an increasing contraction stage and a decreasing contraction stage. Based on these determinations, the controller  104  controls the initial delivery of agent to the balloon body and subsequent delivery and/or discharge of agent to/from the balloon body in the same manner as describe above with respect to the pressure senor configuration. 
         [0046]      FIG. 2  is an illustration of a medical balloon apparatus  102  positioned within an access catheter  202 . The balloon body  112  of the medical balloon apparatus  102  is packaged in a compacted format and shaped to fit within an elongated catheter lumen  204  of the access catheter  202 . The access catheter  202  facilitates access and navigation to a targeted intrauterine cavity location. The access catheter  202  may be a catheter such as described in co-pending U.S. patent application Ser. No. 14/942,577, titled “Intrauterine Access Catheter for Delivering and Facilitating Operation of a Medical Apparatus for Assisting Parturition,” the entire disclosure of which is herein incorporated by reference. The exterior surface of the balloon body  112  is configured to readily slide in a parallel direction within the catheter lumen  204  towards the distal end  206  of the access catheter  202  and outwards into the targeted location in the intrauterine cavity. To this end, the external surface of at least the distal region  110  of the medical balloon apparatus  102  may be coated with materials that increase lubricity of the external surface. 
         [0047]      FIG. 3  is a cross section illustration of the medical balloon apparatus  102  of FIG. 
         [0048]      1 . Although the balloon body  112  is in a collapsed state, it is illustrated in a spaced apart relationship relative to other elements for purposes of clarity. The balloon body  112  defines an internal balloon chamber  302 . The conduit body  106  includes an external region  304 , an internal region  306  within the internal balloon chamber  302 , and an internal lumen  126  that traverses a length of the conduit body. The proximal end  310  of the conduit body  106  includes the connector  114  that is configured to connect to the controller  104 . The distal end  316  of the conduit body  106  terminates approximately at the midpoint  318  of the balloon body  112 . 
         [0049]    The internal lumen  126  traverses the length of the conduit body  106 , forming a hermetic sealed bidirectional fluid conduit between the balloon body  112  and the controller  104 . The walls  312  of the internal region  306  of the conduit body  106  include one or more openings  314  that allow bidirectional fluid conduction from the agent source  118  through the controller  104  into the internal balloon chamber  302 , and from the internal balloon chamber back into the conduit body  106 . The internal lumen  126  communicates with the controller  104  through the connector  114  to provide a fluid communication path for delivery of a gas or fluid agent such as air or saline into the balloon body  112 . 
         [0050]      FIG. 4  is a cross section illustration of the medical balloon apparatus  102  in an expanded, deployed state, including a balloon body  112  of a first configuration. The balloon body  112  is formed by a wall  402  which may be described as having a proximal wall  404 , a distal wall  406 , one or more central or side walls  416  between the proximal wall and the distal wall, and a wall thickness  408 . The balloon body  112  has a maximum diameter  410  defined as the largest distance between the proximal wall  404  to distal wall  406 , and an internal volume  412  defined as the space bounded by the wall  402 . The maximum diameter  410  of the balloon body  112  when inflated is large by medical device standards and may be between 5 cm to 20 cm. In use, the maximum size of the balloon depends on the amount of assistance that might be needed as labor progresses. The interval volume of the balloon body  112  when inflated is also large by medical device standards and may be up to a maximum of 3 liters of volumetric displacement within the balloon body  112 . 
         [0051]    The walls  402 ,  404 ,  406  of the balloon body  112  are made of a soft, flexible, and durable biocompatible material that allows the balloon body to expand to a predetermined shape while withstanding high pressures upon inflation and force application. At the same time, the walls  402 ,  404 ,  406  of the balloon body  112  are thin and flexible enough to allow the balloon body to collapse upon deflation to a size and shape that is flexible enough to contort along a described delivery path. 
         [0052]    During transition from the collapsed state shown in  FIG. 1  and the expanded state shown in  FIG. 4 , the balloon body  112  expands in the direction of the longitudinal axis  414  of the conduit body  106  away from the distal tip  316  of the conduit body. The balloon body  112  also expands in an asymmetric fashion so as to curve back toward the conduit body  106 . 
         [0053]    The balloon body  112  may be configured to distribute forces  422  and direct the degree of expansion of the balloon body in a direction predominantly through a particular wall of the balloon body. Such balloon body  112  configuration may be provided through one of wall thickness design, material property design, or a combination of wall thickness and material property designs. 
         [0054]    In one design, the balloon body  112  may be configured such that the thickness of the central walls  416  is less than the thickness of the proximal wall  404  and the distal wall  406 . The thickness of the distal wall  406  may be greater than or equal to the thickness of the proximal wall  404 . In this design, the central walls  416  are more elastic than the other walls and thus experience a greater degree of expansion upon inflation, relative to the other walls  404 ,  406 . Accordingly, the balloon body  112  deforms to a greater extent in the proximal direction  424 . This greater extent of expansion of the balloon body  112  in the proximal direction  424 , in turn, results in a greater concentration and output of distributed force  422  in the proximal direction  424 . 
         [0055]    In another design, the walls  402 ,  404 ,  406  of the balloon body  112  may have a constant wall thickness  408  throughout and balloon expansion is controlled through the use of different materials having different stiffness/elasticity properties. To this end, the central walls  416  may be formed of a material having less stiffness (higher elasticity) than that of the proximal wall  404  and the distal wall  406 . The elasticity of the distal wall  406  may be greater than or equal to the elasticity of the proximal wall  404 . In one configuration, the proximal wall  404  and the distal wall  406  may be formed of mylar, and the central walls  416  formed of latex. In this design, the central walls  416  again experience a greater degree of expansion upon inflation such that the balloon body  112  deforms to a greater extent in the proximal direction  424 . This greater extent of expansion of the balloon body  112  in the proximal direction  424 , in turn, results in a greater concentration and output of distributed force  422  in the proximal direction. 
         [0056]    In another design, the balloon body  112  may be made of differing materials with different mechanical properties or a differing thickness to control the direction of distribute forces  422  and direct the degree of balloon body expansion in a direction predominantly through a particular wall of the balloon body. For example, the proximal wall  406  may be constructed of thin mylar to reduce the amount of excursion and expansion of this portion of the balloon body  112 , while the central walls  416  may be constructed of thin polyurethane, that allows for a greater degree of expansion by the central walls  416  relative to the other walls  404 ,  406  of the balloon body  112  to thereby limit the amount of forces applied through the central walls  416  and the amount of pressure being exerted against the uterine wall(s), placenta or other internal intrauterine structures that may be adjacent the central walls. 
         [0057]      FIGS. 5A-5C  are schematic illustrations of a balloon body  112  at different stages of expansion. The balloon body  112  includes central walls  416  configured to be more elastic than the proximal wall  404  and the distal wall  406 . The balloon body  112  is characterized by an axis  508  of expansion which corresponds to the axis/direction along which the balloon predominantly expands during inflation.  FIG. 5A  corresponds to an expansion stage of the balloon body  112  at a first internal pressure P 1 , wherein the central walls  416  have a length dimension x. 
         [0058]      FIG. 5B  corresponds to an expansion stage of the balloon body  112  at a second internal pressure P 2  that is greater than the first internal pressure P 1 . At the second internal pressure P 2  the central walls  416  of the balloon body stretch to a dimension x+Δ1. The change in dimension of the central walls  416  results in expansion of the balloon body  112  and movement of both the proximal wall  404  and the distal wall  406  in generally opposite directions relative to each other and along the axis  508 . For example, with respect to fixed point  502  on the axis  508 , the distal wall  406  is displaced in a first direction  506  while the proximal wall  404  is displaced in a second direction  504 . The amount by which the proximal wall  404  is displaced is greater than the amount by which the distal wall  406  is displaced. In other words, the degree of displacement of the proximal wall  404  exceeds the degree of displacement of the distal wall  406 . 
         [0059]      FIG. 5C  corresponds to an expansion stage of the balloon at a third pressure P 3  that is greater than the second pressure P 2 . At the third pressure P 3  the central walls  416  of the balloon body  112  stretch to a dimension x+Δ2. The change in dimension of the central walls  416  results in further expansion of the balloon body  112 , and corresponding displacement of the distal wall  406  in the first direction  506  and displacement of the proximal wall  404  in the second direction  504 . Again, with respect to point  502  along the axis  508 , the displacement of the proximal wall  404  exceeds the displacement of the distal wall  406 . 
         [0060]      FIG. 6  is a cross section illustration of the medical balloon apparatus  102  in an expanded, deployed state, including a balloon body  112  of an alternate configuration. In this design, the balloon body  112  contains one or more tension bearing structures  602  located within the interior chamber  604  of the balloon body  112 . These one or more tension structures  602  span the interior chamber  604  to thereby create one or more interior sub-chambers. In the configuration shown in  FIG. 6 , the interior chamber  604  is divided into a first sub-chamber  606  and a second sub-chamber  608  by a single tension bearing structure  602 . The tension structures  602  may include one or more openings  618  through which pressurized agent passes between adjacent sub-chambers  606 ,  608 . 
         [0061]    While the configuration shown in  FIG. 6  has one tension bearing structure  602 , more than one tension bearing structure may be included. In this design, the balloon body  112  may be described as having a first sub-balloon  610  having a first sub-balloon wall  612 , and a second sub-balloon  614  having a second sub-balloon wall  616 . The first sub-balloon wall  612  and the second sub-balloon wall  616  may be constructed, through one or more of a wall thickness characteristic and a material property characteristic, such that the first sub-balloon wall  612  experiences a greater degree of expansion than the second sub-balloon wall  616 . As such, a greater extent of expansion of the balloon body  112  in occurs in the proximal direction  424 , in turn, results in a greater concentration and output of distributed force  422  in the proximal direction  424   
         [0062]      FIG. 7  is an illustration of the medical balloon apparatus  102  positioned in an intrauterine cavity, while in a collapsed, pre-deployed state. During maternal labor upon desired use of the medical balloon apparatus  102 , the packaged, pre-deployed balloon apparatus is inserted via the cervical canal  702  and the distal tip  704  of the balloon body  112  is navigated within the uterine cavity space  706  and along the uterine walls  708   a,    708   b,    708   c  to circumnavigate the fetus  710 , umbilical cord  712 , and placenta  714  until the balloon body  112  is placed at a target location near the fundus  716  of the uterus. As shown, this location is proximal to the fetus  710  and birth canal, within a uterine cavity space adjacent to the base  718  of the fetus with a cephalic presentation. 
         [0063]    Insertion, navigation, and placement of the medical balloon apparatus  102  may be performed using an access catheter  200 , such as shown in  FIG. 2 , and further described in co-pending U.S. patent application Ser. No. 14/942,577, titled “Intrauterine Access Catheter For Delivering and Facilitating Operation of a Medical Apparatus For Assisting Parturition”. To aid in proper orientation of the medical balloon apparatus  102  so the proximal wall  404  is facing the infant, the access catheter  200  includes markers that provide an indication of both direction and depth of insertion of the catheter. The balloon body  112  may include similar markers on the proximal wall  404 . Furthermore, the torque rigidity of the conduit body  106  is high enough so that the rotations along the conduit result in rotation of the pre-inflated balloon. Accordingly, the user may ensure proper orientation of the balloon body  112  based on the orientation of the markers on the access catheter  200 , and possible additional markers on the balloon body  112 . 
         [0064]      FIG. 8  is an illustration of the medical balloon apparatus  102  positioned in an intrauterine cavity, while in an expanded, deployed state. After placement of the distal tip of the balloon body  112  at the targeted location, the balloon is deployed by injection of pressurized agent  124  through the internal lumen  126  of the conduit body  106 . The balloon body  112  expands to reach pressure equilibrium. Injection of the pressurized agent  124  into the internal lumen  126  causes the balloon body  112  to expand predominantly in the direction of the cervical canal  702 . This expansion of the balloon body  112  results in the application of distal forces  802  towards the base  718  of the fetus  710  and towards the cervical canal  702 .  FIG. 8  shows the balloon body  112  during expansion relative to the fetus  710 , umbilical cord  712 , placenta  714 , uterine walls  708   a,    708   b,    708   c,  and cervical canal  702 . 
         [0065]    Throughout inflation of the balloon body  112 , the proximal wall  404  of the balloon body faces the fetus  710  and cervical canal  702 . Due to the previously described designs of the balloon body  112 , the balloon body predominantly expands in the direction generally along an axis  804  passing through the uterus and the cervical canal  702 . Accordingly, directional forces  802  resulting from expansion of the balloon body  112  are applied to the base  718  of the fetus. As the fetus  710  descends, the balloon body  112  is further expanded in order to maintain the application of the directional forces  802 . As such, directional forces  802  are applied throughout infant descent through the cervical canal  702 . Predominant expansion of the balloon body  112  in the direction along the axis  804  in the direction of the cervical canal  702  reduces expansion of the balloon body in other directions. This is beneficial in that it reduces the amount of forces applied to other intrauterine structures, e.g., the uterine walls  708   a,    708   b,    708   c,  and parts of the fetus  710  other than the base  718 . 
         [0066]      FIG. 9  is a flow chart of a method of augmenting expulsive intrinsic uterine forces towards a cervical canal during delivery of a fetus from a uterus. The method may be performed by the medical balloon system  100  of  FIG. 1 . 
         [0067]    At step  902 , the system  100  monitors an intrinsic uterine contraction. The intrinsic uterine contraction may be an onset of a contraction or it may be a change in state of an occurring contraction that results in either an increase in intrinsic intrauterine pressure or forces or a decrease in intrinsic intrauterine pressure or forces. The onset and pressure state of a uterine contraction may be monitored for by the controller  104  based on electrical activity sensed from the uterus and the processing of the sensed electrical activity. For example, morphology analysis of the sensed electrical activity may detect an onset of a contraction and changes in the pressure state of the contraction. The onset and pressure state of a uterine contraction also may be monitored for by the controller  104  based on sensed pressures. In one configuration, pressures are sensed through the conduit body  106 , wherein such pressures are indicative of pressure within the uterus. In another configuration, an intrauterine pressure measurement may be obtained from a pressure sensor associated with a medical balloon apparatus  102  that is delivered in the uterus. 
         [0068]    At step  904 , if an onset of an intrinsic uterine contraction or a change in state of an ongoing contraction is not detected by the system  100 , the process returns to step  902 . If onset of an intrinsic uterine contraction or a change in state of an ongoing contraction is detected, the process proceeds to step  906 , where the system  100  mediates a force generated via a medical balloon apparatus  102  located in the uterus. The force is directed toward the cervical canal and augments natural expulsive uterine forces. In one configuration, the medical balloon apparatus  102  includes a balloon body  112  positioned at a proximal uterine location adjacent the fetus. For example, as shown in  FIG. 8 , the balloon body  112  may be positioned between the base  718  of the fetus  710  and the fundus  716 . The force is generated by delivering an agent to the balloon body  112  to thereby expand the balloon body toward the cervical canal  702  and into contact with the base  718  of the fetus  710 . 
         [0069]    Upon either of a detection of an onset of an intrinsic uterine contraction, or an increase in uterine contraction forces, the system  100  may mediate the force by delivering an agent to the balloon body  112  to at least partially expand the balloon body toward the cervical canal  702  and into contact with the base  718  of the fetus  710 . Upon a detection of a decrease in uterine contraction forces, the system  100  may mediate the force by discharging an agent from the balloon body  112  to at least partially collapse the balloon body away from the fetus  710  and the cervical canal  702 . As a safety measure, the system  100  may also mediate the force by discharging an agent from the balloon body  112  when a measured pressure associated with the medical balloon apparatus exceeds a threshold value, such as 200 mmHg. 
         [0070]    The forces applied by the medical balloon apparatus  102  are mediated by increasing and decreasing the agent delivered through the conduit body for constructively augmenting uterine pressures generated by intrinsic contractions. The target pressure or pressure based objective is set within the controller  104  and used for defining the target balloon pressure resulting from agent delivery. To this end, the controller  104  may include a memory for storing program code and a processor that operates in accordance with the code to implement the process of  FIG. 9 . Accordingly, the controller  104  may be considered a special purpose computer that is configured to—in conjunction with a medical balloon apparatus  102  having a balloon body  112  configured to be positioned in the uterus—monitor an intrinsic uterine contraction, and mediate a force generated via the balloon body during the intrinsic uterine contraction, wherein the force is directed toward the cervical canal and augments natural expulsive uterine forces. 
         [0071]    The controller  104  is further configured to implement subprocesses associated with monitoring and mediating. For example, the controller  104  may be configured to monitor an intrinsic uterine contraction by obtaining one or more of pressure signals and electrical signals indicative of an intrinsic uterine contraction. As described above, these signals may be provided by sensors associated with the medical balloon apparatus. The controller  104  includes program code that allows the processor of the controller to detect at least one of an onset of an intrinsic uterine contraction, an increase in uterine contraction forces, and a decrease in uterine contraction forces based on the one or more of pressure signals and electrical signals. To this end, the controller may process the signals to obtain corresponding measurements and compare the measurements to threshold values stored in memory that represent a contraction onset, or a change (e.g., increase or decrease) in uterine contraction force that warrants mediation. 
         [0072]    With respect to mediation, the controller  104  may be configured to deliver an agent to the balloon body  112  to at least partially expand the balloon body toward the cervical canal and into contact with the fetus upon either of a detection of an onset of an intrinsic uterine contraction, or an increase in uterine contraction forces. The controller  104  may be configured to discharge an agent from the balloon body  112  to at least partially collapse the balloon body away from the fetus and the cervical canal upon a detection of a decrease in uterine contraction forces. As describe previously, an increase or decrease in uterine contraction forces may be warranted when the controller  104  detects a corresponding increase or decrease in pressure due to intrinsic uterine activity that satisfies a threshold criterion. The controller  104  may also be configured to discharge an agent from the balloon body  112  when a measured pressure associated with the medical balloon apparatus exceeds a maximum allowed threshold value. 
         [0073]    The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. For instance, the conduit body  106  and the internal lumen  126  geometry may vary depending on the catheter delivery system, the expanding balloon may vary within a range of sizes and shapes, and the balloon may have varying thicknesses or radius of curvatures, and the bidirectional conduit may utilize more than one lumen. 
         [0074]    Furthermore, while the configuration described herein were with respect to a balloon apparatus in the form an inflatable membrane, other balloon apparatuses or expandable members may be employed. For example in an alternative configuration, the balloon apparatus/expandable member deployed from the distal tip of the catheter may be a gel based bio-compatible substance expulsed from the lumen of the catheter. The substance may configured to have a strong surface tension that enables pressure applications towards the infant and birth canal while conforming to the size and shape of the uterine space and infant. In yet another alternative configuration, the balloon apparatus/expandable member may be a viscous bio-compatible polymeric fluid with a memory shape causing the formation of a shape upon contact with one or more substances contained within the amniotic fluid. 
         [0075]    Disclosed herein is an intracorporeal medical device  102  capable of monitoring and delivering pressure to the uterine wall or infant(s) for the purpose of managing the birthing delivery process. The medical device  102  is delivered to a target location in an intrauterine or extrauterine location adjacent to the uterine wall. The medical device  102  may be delivered to a target location with the use of a catheter, separate delivery system, or surgical insertion, and is deployed or inflated once it is at or near its targeted location. The medical device  102  administers therapies, pressure and/or forces, fluids, or therapeutic agents to assist the birthing process. 
         [0076]    The medical device  102  together with a controller  104  form a medical system  100  that monitors the onset or occurrence of uterine contractions and other muscle activity including abdominal contraction. The medical system  100  times the delivery of therapy including the direction and degrees of applied forces relative to the occurrence of natural uterine contractions or other muscle activity during labor. The medical system  100  may incorporate physiologic mechanical measures of birthing resistance including fetal-pelvic, fetal-birth canal, or fetal-uterine pressures. The medical system  100  may employ one or more mechanisms to vary the direction and magnitude of forces applied to the uterine walls, fetus, or other anatomical structures. The medical system  100  may include markers on the medical device  102  that enable visualization of the intrauterine cavity during the birthing process including geometrical relationships of the uterine wall, birth canal, one or more infant(s), placenta, or umbilical cord(s). 
         [0077]    The medical device  102  includes a balloon body  112  that is made from silicone, polyvinyl chloride, latex, or other similar substance capable of being inflated and deflated, or applying pressure in a reliable repeatable manner while maintaining pliability. The medical device  102  may include one or more sensors for detecting and monitoring intrauterine forces and directions due to passive uterine and abdominal stretch, abdominal muscle contractions, myometrial uterine muscle contractions, or other externally actively applied forces. These sensors may be located on the balloon body  112  or the conduit body  106  of the medical device  102 . The medical system  100  utilizes algorithms for defining upper levels of applied pressure levels to reduce the likelihood of damage to the infant or maternal organs specifically the infant head and shoulders, and maternal uterine cavity, birthing canal, umbilical cord, and placenta. The medical system  100  also utilizes sensors and algorithms for monitoring indices of physiologic birthing including infant heart rates, maternal stress measures, umbilical cord flow, infant perfusion. The medical device  102  and system  100  may be used acutely to assist the intrapartum delivery process, or chronically to monitor and manage the prepartum to intrapartum periods of the birthing delivery process. 
         [0078]    Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”