Obstetrics Introduction Flashcards
What is gravidity
The number of times a woman has been pregnant, including her current pregnancy
What is parity?
The number of times a woman has given birth after 24 weeks gestation. Multiple births count as the multiple, not a single.
What are the common indication for obstetrician led care?
Medical: hypertensive disease, diabetes
Age: over 40 years
Previous caesarean section
Previous complicated pregnancy
What general advice is offered to pregnant women?
Work: avoid occupational risk factors
Supplements: folic acid 400mcg, pre-conception to 12 weeks; avoid vitamin A supplements
Food: avoid liver; avoid unpasteurised dairy products; avoid partially cooked eggs and meats
Alcohol: avoid alcohol completely up until 3 months; limit of 1-2 units a week
Smoking: cessation advice
Exercise: moderate levels are good; pelvic floor exercises
Travel: wear seatbelt above/below bump, not over it
What is the usual antenatal programme for nulliparous women in terms of appointments and scans?
- Booking visit plus 10 appointments is the recommendation (7 for parous women)
- Dating scan at 10-14 weeks, anomaly scan at 18-20 weeks, later scans only if indicated
What is done at the booking visit?
- A full obstetric history
- A full medical history
- Measurements: BP, BMI, Urine dip
- Bloods: FBC, BM, group, rhesus, Hb (if indicated)
- Infection Screen: HIV, HepB, Rubella, Syphilis
- Dating scan (viability, heart beat, multiple)
Describe the screening for Down’s Syndrome before 15 weeks gestation
Combined test:
- Nuchal Translucency (raised with Down’s)
- beta Human Chorionic Gonadotrophin (raised with Down’s)
- Pregnancy associated Plasma Protein A (lowered with Down’s)
beta HCG and PAPP-A is produced by placental syncytiotrophoblasts
If positive (>1 in 150 risk) offered further testing
Describe the screening for Down’s Syndrome after 15 weeks gestation
Quadruple test:
- Alpha fetoprotein (reduced in Down’s)
- Unconjugated oestradiol (reduced in Down’s)
- Beta HCG (raised in Down’s)
- Inhibin A (raised in Down’s)
Describe the two diagnostic tests for Down’s Syndrome, their complications, and when they are performed.
What are the key differences?
Chorionic Villous Sampling:
- At <15 weeks gestation
- A sample of the placenta is taken
- Risks miscarriage, amniotic fluid leakage, and sepsis
Amniocentesis:
- At >15 weeks gestation
- A sample of the amniotic fluid is taken (1ml for each gestational week)
- Risks miscarriage, infection, failure, amniotic fluid leakage
Differences:
- CVS is quicker than amniocentesis
- Amniocentesis is more accurate than CVS
- Amniocentesis is safer than CVS if performed after 15 weeks
What is looked for in the anomaly scan?
- Neural tube defects
- Cardiac defects
- Renal defects
- Cleft lip and palate
- Talipes Equinovarus
- Duodenal atresia (solid duodenum; polyhydramnios and double bubble on ultrasound)
- Low lying placenta
- Foetal measurements
What is the lie of a foetus?
The position of the longitudinal axis of the child, with the longitudinal axis of the mother.
Only longitudinal lie is normal. Transverse or oblique require version.
What is the presentation of a foetus?
This is the presenting part of the foetus; can be either cephalic or breech.
What is the position of the foetus?
This refers to the specific part of the presenting body. Examples include right occipito-anterior, left occipito-anterior
What is the engagement of the foetus?
This is the extent to which the presenting part has entered the pelvis. It is measured in 5ths, and when the presenting part is less than 2/5ths palpable, it is engaged.
This usually occurs at 36 weeks in a nulliparous woman, and sometimes after the onset of labour in a multiparous woman.
