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

Read about Intrapartum Care in VBAC-

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

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.

• Anthracyline regimens are safe
• There are fewer data on taxanes, which should be reserved for high-risk (node-positive) or metastatic disease.
• Tamoxifen is not used until after delivery.
• Trastuzumab  is contraindicated during pregnancy.
• Haemopoietic growth factors (granulocyte colony stimulating factor) may be employed to ameliorate chemotherapy-induced neutropenia.

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

Planned VBAC is associated with an approximately 1 in 200 (0.5%)
risk of uterine rupture

A systematic review reported that women with one, two, or three or more previous caesarean deliveries experience a 1%, 1.7% or 2.8% risk of placenta previa in a subsequent pregnancy. ( Source- Birth After Previous
Caesarean Birth Green-top Guideline No. 45 ).

Assisted reproductive technology ( RR- 3.71, OR 2.67)and maternal smoking ( OR 1.42)  increase the risk of placenta praevia.

Previous vaginal delivery, particularly previous VBAC, is the single best predictor of successful VBAC and is associated with a planned VBAC success rate of 85–90%.

Previous vaginal delivery is also independently associated
with a reduced risk of uterine rupture.

• 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.

• The timing of delivery should be tailored to the patient.
• If history of vaginal bleeding/ other risk factors for preterm delivery- consider ‘Late preterm delivery’- 34+0 to 36 +6 weeks.
• If uncomplicated placenta previa- Consider between 36+ 0 and 37+0.

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

Risk of anal sphincter injury in women undergoing VBAC is 5%.

Birthweight is the strongest predictor of anal sphincter injury in women undergoing VBAC.