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.

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).

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.

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)

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

Caesarean section is the recommended mode of delivery in cases of cord prolapse when vaginal birth is not imminent in order to prevent hypoxic acidosis.
Category 2 caesarean birth can be considered for women in whom the fetal heart rate pattern is normal, but continuous assessment of the fetal heart trace is essential.

In case of cord prolapse in advanced labor , delivery should be expedited.

A document on categories of Caesarean section can be found here-CLICK HERE

- 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.

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

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

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

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)

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.

• 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.

• 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.