- Inefficient Uterine Powers- most common cause for induced labour, not enough dilatation and weak contractions.
- Hyperactive uterine action – too many or too strong contractions associated with overly high oxytocin levels. Can lead to fetal compromise.
- Cephalo pelvic disorder – Some women have a very small pelvic, which are too small for the baby’s head. Labour wont progress past cervical dilation and a C-section is required. If you suspect a woman has a small pelvic always attempt vaginal delivery first.
- Occipito anterior position – This is normal. Baby faces mum’s bum.
- Occipito posterior presentation – Abnormal. Baby is back to back to mother, due to failure to rotate to normal position. Labour is longer and more painful. A ‘dip’ in the mother’s abdomen is felt, and they commonly complain of backache. Risk factors are high BMIs, low activity and primipara mothers.
- Occipito transverse position – Abnormal. Baby looking to side, due to incomplete normal rotation. Can be significant as can cause normal vaginal delivery to arrest. When waters break lots more fluid comes out, as the baby’s head does not ‘plug’ the cervix. The dramatic loss in fluid and pressure can cause severe problems:
- Cord prolapse
- Arm delivery/ arm presentation
- Placental abruption
- Brow presentation – causes the baby’s head to extend rather than flex. A vaginal exam shows forehead and nose. C-section is required. Face presentation is similar but with a greater level of neck extension.
- Breech Presentation –Abnormal. Legs or buttocks first, as opposed to the normal cephalic presentation where the head is the presenting part.
Instrumental delivery is used to shorten a lengthy second stage of labour to make it safer for mother and baby. Long second stage is considered to be >45mins for multipara and >95mins for first timers, and risks fetal compromise.
- Forceps– there are two types; rotational and non rotational. As can be very uncomfortable for mothers and pudendal nerve block is commonly given for analgesia.
Side effects of instrumental deliveries
- Maternal – vaginal lacerations, PPH and 3rd degree tears
- Fetal – scalp lacerations, haematoma on head, jaundice (due to RBC breakdown in haematoma) in ventouse deliveries. Facial nerve damage (Bell’s palsy), fractures, facial bruising in forceps delivery.
Indications for instrumental delivery
- Fetal compromise
- Prolonged second stage and maternal exhaustion
- Prophylactic in cases of maternal hypertension and cardiac disease
- Breech Presentation (instrumental delivery required for head at end of second stage)
Pre-requisites for instrumental delivery
Head not palpable abdominally
- Head at or below ischeal spines
- Cervix fully dilated
- Position of head known
- Analgesia given
- Valid indication
- Bladder empty
Other types of management
- Augmentation – Membrane Sweep, Prostaglandins, Amniotomy (artificial rupture of membranes) and oxytocin (helps dilate cervix and speed up labour)
- External Cephalic Version – manual rotation of baby from transverse or breech to cephalic presentation. Tubilene should be given first to soften the uterus