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.

- 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.

Read about Intrapartum Care in VBAC-

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

The likelihood of maternal GBS carriage in this pregnancy is 50%.
What should be done?- Discuss the options- a. Intrapartum antibiotic prophylaxis ( IAP).
b. Bacteriological testing in late pregnancy and the offer of IAP if still positive. ( This is the only group of women who are eligible for GBS screening funded by NHS)

It should be done at 32–34 weeks of gestation for women with twins.

The recommended time of testing is 3–5 weeks prior to the anticipated delivery date- therefore  35–37 weeks of gestation in singleton pregnancies with no risk factors for preterm delivery.

For potentially sensitising events after 20weeks gestation,
a minimum anti-D Ig dose of 500 IU should be administered within 72 h of the event.

After collection, swabs should be placed in a non-nutrient transport medium, such as Amies or Stuart. Specimens should be transported and processed as soon as possible. If processing is delayed, specimens should be refrigerated. When testing for GBS, the lab should be specifically informed that the swab is for GBS testing.

This is GBS bacteruria. GBS bacteriuria is associated with a higher risk of chorioamnionitis and neonatal disease. Women with GBS bacteriuria should be offered IAP.

Women with GBS urinary tract infection (growth of greater than 10^5 cfu/ml) during pregnancy should receive appropriate treatment at the time of diagnosis as well as IAP. 

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.

Successful VBAC is more likely among women with previous caesarean for
fetal malpresentation (84%) compared with women with previous caesarean for either labour dystocia (64%) or fetal distress (73%) indications.

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.

• 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.

In pregnancies<12 weeks gestation, anti-D Ig prophylaxis is only indicated following ectopic pregnancy, molar pregnancy, therapeutic termination of pregnancy and in
cases of uterine bleeding where this is repeated, heavy
or associated with abdominal pain. The minimum dose should be 250 IU. A test for fetomaternal haemorrhage (FMH) is not required

Non-hormonal contraceptive methods are recommended.

According to UKMEC- For women with 'Current breast cancer' , Cu IUCD is Category 1 , all other contraceptive methods are category 4.

For women with 'Past' breast cancer' , Cu IUCD is Category 1 , all other contraceptive methods are category 3.

Routine ultrasound screening is not useful. Selective ultrasound screening can be considered for women with breech presentation at term who are considering vaginal birth.