Labour and The Stages of Labour .pptx

Stages of labour

1. MANAGEMENT OF LABOUR DR. ‘BAYO ADEKUNLE Lecturer Consultant Obstetrician and Gynaecologist . College of Health Sciences, LAUTECH.

2. LEARNING OBJECTIVES At the end of the lecture, students should know: The definition of Labour Theories of onset of Labour Mechanism of Labour Stages of Labour and management

3. LEARNING OBJECTIVES (Cont.) Physiology of normal Labour Active management of third stage of Labour Summary Conclusion

4. Definitions Series of evets that takes place in the genital organs in an effort to expel the product of conception (fetus, placenta and membranes) out of the womb through the vagina.

5. Definitions (Cont.) Labour is also defined as onset of palpable, regular and painful uterine contractions leading to the dilation and effacement of the cervix with descent of the fetus and eventual delivery

6. Definitions (Cont.) World Health Organisation (W.H.O.) defines NORMAL LABOUR (EUTOCIA) as a retrospective diagnosis characterised by spontaneous onset of Labour at term In a low risk pregnancy with eventual delivery of the infant in vertex position and with mother and infant in good condition after birth. Any deviation from the above description of Normal Labour is called Abnormal Labour (DYSTOCIA)

7. Successful Labour and delivery is dependent on complex interaction of 3 variables (three ‘P’s) ( i ) Power (contraction) (ii) Passenger (fetus) (iii) Passage (pelvis)

8. THEORIES OF ONSET OF LABOUR The precise mechanism of the initiation of human labour is still obscure, endocrine, biochemical and mechanical stretch pathways has the following hypothesis; Uterine distension theory : Stretching effects of the uterus increases gap junction proteins and oxytocin receptors leading to onset of labour ( e.g. polyhydramnios & twin pregnancy)

9. THEORIES OF ONSET OF LABOUR (Cont.) Fetoplacental contribution: Fetal hypothalamic pituitary adrenal axis leading to increase of cortisol production and eventual increase in estrogen and prostaglandins from placenta which leads to increase in calcium production and eventual uterine contractions. Prostaglandins are the important factors which initiate and maintain labour .

10. THEORIES OF ONSET OF LABOUR (Cont.) Oxytocin and myometrial oxytocin receptors: There is increase in oxytocin & oxytocin receptors near term reaching maximum during labour and this leads to increase in prostaglandins (E 2 & F 2 ) and eventual uterine contractions.  

11. THEORIES OF ONSET OF LABOUR (Cont.) Neurological factors: Increase in estrogen compared to prosgesterone near term during labour leads to increase in receptors of the post- gonglonic nerve fibers in and around the lower part of the uterus and cervix, this also may explain onset of labour .  

12. STAGES OF LABOUR Conventionally, events of labour are divided into three stages. First stage of labour : From the onset of uterine contractions to full dilatation of the cervix (10cm). 1 st stage of labour is divided into two phases. Latent phase : onset of labour to 3cm cervical dilation. Effacement is usually complete during this phase. Usually lasts between 3-8 hours. Active Phase: From 4cm cervix dilatation to full dilatation (10 cm) .

13. MECHANISM OF LABOUR MECHANISM OF LABOUR: Series of events and movements of the head in the process of adaptation during its passage through the pelvis. E. D. F. I. E. R. E. Engagement: The head enters the pelvis to assume a favourable diameter and engagement is set to occur when the widest part of the presenting part has passed successfully through the inlet.

14. MECHANISM OF LABOUR (Cont.) Descent : Usually occurs to ensure further progress of labour . Flexion: This is to minimize the presenting diameter of the fetal head. Internal rotation: The occiput is forced to lie anteriorly as it approaches the pelvic outlet.

15. MECHANISM OF LABOUR (Cont .) Extension : This occurs as the head extends further underneath the pubic symphysis. Restitution: The head aligns with the shoulder. External rotation: The occiput rotates back to the transverse position and delivery ensures .

16. STAGES OF LABOUR (Cont.) Second stage of labour : This describes the time from full dilation to delivery of the fetus or fetuses. Also divided into a pelvic (passive) phase and a perineal phase (Active phase). The perineal (Active) second stage is usually characterized by a maternal urge to push. Usually last no longer than 2hours in primiparous women ( 3 hours if on epidural anesthesia) and no longer than 1hour in multiparous ( 2hours if on epidural anesthesia)

17. STAGES OF LABOUR (Cont.) Third stage of labour : Time from delivery of fetus until delivery of placenta. Usually considered abnormal (prolonged third stage) if lasting more 30 minutes.

18. MANAGEMENT OF LABOUR Management of first stage of labour Non interference with watchful expectancy Women are given encouragement, social support and adequate pain relief during the entire course of labour

19. MANAGEMENT OF LABOUR (Cont.) Management of first stage of labour (Cont.) Monitor carefully the progress of labour , feto -maternal condition so as to detect any deviation from normal Maintain a partograph Partograph : It is a graphical representation of all the events of labour

20. MANAGEMENT OF LABOUR (Cont.) Management of second stage of labour To assist in natural expulsion of the fetus slowly and steady To prevent perineal injuries, timely performed episiotomies when indicated Immediate care for the newborn

21. Active management of third stage of labour The underlying principle in active management is to ensure powerful uterine contractions within 1 minute of delivery of the baby (WHO). It facilitates not only early separation of placenta but also provide effective uterine contractions following its separation.

22. Active management of third stage of labour (Cont.) It has four components: Delivery of the placenta by controlled cord contraction. Administration of injection oxytocin 10 I.U intramuscularly within 1 minute of delivery of the baby. Uterine massage. Early cord clamping.