Normal labour and delivery is a physiologic process in
which the attendant closely monitor the woman and fetus, with little medical intervention required. Friedman developed the concepts of 3 functional divisions of labor to describe the physiological objectives of each divisions.
i ) Preparatory division / Latent phase :
little cervical dilatation, This divisions of labor may be sensitive to sedation and conduction of analgesia .
ii ) Dilatational divisions / Active phase :
The dilatation proceeds at its most rapid rate . It is unaffected by sedation or conduction analgesia. iii ) Pelvic divisions / Transition phase :
Commences with deceleration of cervical dilation.
Active labor is defined as 3 to 4 cm or more cervical dilatation with good uterine contraction.
It is the process of expulsion of fetus, placenta and its membranes through the birth canal.
NORMAL LABOUR / EUTOCIA :
Normal labor occurs at term, spontaneous in onset, fetus presenting by the vertex, it complete within 18 hours, no complication arise.
STAGES OF LABOUR :
First stage (or) Dilating stage
Second stage (or) Pushing stage (or) pelvic stage
Third stage (or) Placental stage
Fourth stage (or) Recovery stage
FIRST STAGE OR DILATING STAGE :
It starts with regular and rhythmic uterine contractions till completion of full cervical dilatation (10cm).
For primi gravida 16hrs to 18hrs.
For multi gravida 6hsrs to 10hrs.
ONSET OF LABOUR :
It is the term given to the last few weeks of pregnancy during this period number of changes occur.
2 to 3 weeks before the onset of labor the lower uterine segment expands and allows the fetal head to sink down to lower uterine segment which causes head engagement . So the fundus no longer crowds the lungs, leads to easy breathing. Heart and stomach function more easily and women feel relief .Head engagement will be after 36 weeks in primigravida and in multigravida 2hrs before the onset of labour.
3. Frequency of micturition :
congestion in the pelvis limits the capacity of the bladder, requiring it to be emptied more often . Laxity of the pelvic floor muscles may give rise to poor sphincter control and a degree of stress incontinence.
4.Taking up of cervix and Cervical Effacement :
The cervix is drawn up and gradually merges into the lower uterine segment is called as cervical effacement, leads to cervical dilatation. In primigravida cervical effacement will be first taking place then cervical dilatation. But in multigravida Cervical effacement and cervical dilatation will be spontaneous in onset .
5. Difference between True labor and False labor :
Niggling / Spurious labor / False labor | True labor |
Uterine contraction : Not always present Lasts for 3 to 4 minutes Irregular Felt in lower back radiates to lower Portion of abdomen May or may not be painful Can stop with comfort measures No back ache Intensity stop with position changes, WalkingCervix : No shortness , Soft No dilatation No tensed membrane Posterior position No showFetus : No head engagement | Uterine contraction : Always present Not exceed > 90 seconds Regular and rhythmic Felt in back or abdomen above navel Abdominal tightening ,discomfort and Pain will stop with comfort measures May have back ache Increase with intensity walkingCervix : Shortening Dilatation Tensed membrane Anterior position Show presentsFetus : Head engagement |
CAUSES OF ONSET OF LABOR :
Exact cause is unknown .
i ) Hormonal factors :
Formation of Oxytocin receptors in uterine muscles by the influence of Estrogen . Which act with Prostaglandin secreted from Decidua and membrane triggers the uterine contraction . Emotional and physical stress stimulates Hypothalamus to release Oxytocin which triggers the uterine contraction .
ii ) Mechanical factors :
Pressure exerted by presenting part to the os of cervix initiates uterine contraction PHASES OF FIRST STAGE OF LABOR :
Have 3 phases
* Latent phases
* Active phases