- 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).

If the distance between the internal os and the placental edge is 20 mm or more on TVS, the placental location should be recorded as normal and managed as per routine

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

The RAADP scheme should be regarded as supplementary to any anti-D Ig administered for sensitising episodes.

• If the history suggests that the reaction described is not likely to be allergic in nature then penicillin should be given.
• If the history suggests an allergy to beta-lactams, but one that is not severe(i.e. no anaphylaxis, angioedema, respiratory distress or urticaria), then a cephalosporin can be administered.
• If the allergy to beta-lactams is severe then intravenous vancomycin is recommended.

GBS is present in the bowel flora of 20–40% of adults (this is called ‘colonisation’). People who are colonised are called
‘carriers’. This includes pregnant women (there is no evidence that its carriage rate is specifically affected by pregnancy).

Read about Intrapartum Care in VBAC-

https://obgresource.com/2021/12/10/intrapartum-care-in-vbac-2/

Planned VBAC is contraindicated in women with previous uterine rupture or classical caesarean scar.

Women who have had two or more prior lower segment caesarean deliveries may be offered VBAC after counselling by a senior obstetrician. This should include the risk of uterine rupture and maternal morbidity, and the individual likelihood of successful VBAC.

The recommended dose is - 3 g intravenous benzylpenicillin be given as soon as possible after the onset of labour  and 1.5 g 4 hourly until delivery.
The first dose should be given at least 4 hours prior to delivery.

• No screening test is entirely accurate.
• 17% to 25% of women who have a positive swab at 35–37 weeks of gestation will be GBS negative at delivery.
•  5% to 7% of women who are GBS negative at 35–37 weeks of gestation will be GBS positive at delivery.
• Many of the babies who are severely affected from GBS infection are born prematurely, before the suggested time for screening.

Methotrexate adjuvant therapy should not be used for expectant management as it is of unproven benefit and has significant adverse effects.

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

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.

Cord presentation is the presence of the umbilical cord between the fetal presenting part and the cervix, with or without intact membranes. ( i.e if the cord  is present ABOVE the cervix, with ruptured membranes- this is cord PRESENTATION)

Cord prolapse is descent of the umbilical cord through the cervix  in the presence of ruptured membranes.

Cord prolapse can be occult ( Alongside the presenting part) or OVERT (Past the presenting part)

When testing for GBS carrier status, a swab should be taken from the lower vagina and the anorectum.

A single swab (vagina then anorectum) or two different swabs can be used.