In the first stage of labour, pain is transmitted via
the spinal nerves of T10–L1 and results from uterine
contractions and dilatation of the cervix. In the second
stage, stretching of the pelvic ligaments causes pain via the
pudendal nerve originating from the S2–S4 nerve roots.

If the placenta is thought to be low lying (less than 20 mm from the internal os) or praevia
(covering the os) at the routine fetal anomaly scan, a follow-up ultrasound examination
including a TVS is recommended at 32 weeks of gestation to diagnose persistent low-lying
placenta and/or placenta praevia.

Use of TVS- to accurately see the placental edge. Also, cervical length is a predictor of antepartum bleeding and emergency preterm caesarean section in placenta praevia. Women with a cervical length of less than 31 mm have a 16 times higher risk of emergency
caesarean section due to massive haemorrhage.

• If pharmacological measures fail to control the haemorrhage, surgical interventions should be initiated sooner rather than later.
• Intrauterine balloon tamponade is an appropriate first-line ‘surgical’ intervention for most women where uterine atony is the only or main cause of haemorrhage.

Conversion from LMWH back to warfarin should be delayed for at least 5 to 7 days after delivery
to minimise the risk of haemorrhage during the period of overlap of LMWH and warfarin treatment.

Conception during tamoxifen therapy should be avoided because
of potential teratogenicity, and a ‘washout period’ of 2–3 months is advised

- For pregnancies at more than 16 weeks of gestation the term low-lying placenta should be used when the placental edge is less than 20 mm from the internal os on transabdominal or transvaginal scanning (TVS).

• The term placenta praevia should be used when the placenta lies directly over the internal os.

The algorithm suggested by RCOG for low lying placenta can be accessed HERE 

According to the RCOG Guidance, it is 39%

If non-surgical management for stress urinary incontinence has failed, and the woman wishes to think about a surgical procedure, offer her the choice of:
- colposuspension (open or laparoscopic) or
- an autologous rectus fascial sling.