• Detect correctable abnormalities of mother and foetus
• Ultimate aim of antenatal care is to delivery each healthy mother a healthy baby without handicap of detriment to either
• Congenital abn: not treatable, therefore offer counselling

• Calculate expected date of confinement (EDC) from last menstrual period (LMP)
• EDC usually at 40 weeks after LMP on the assumption that the woman has regular 28-day menstrual cycle and will ovulate at 14^th day of the cycle

1. Eg. LMP = 01.01.99, EDC = 08.10.99
2. Eg. LMP = 01.07.99, EDC = 08.04.00 (add one year to EDC in this case)

• Naegele's rule: 28-day cycle, EDC can be calculated by subtracting 3 months from date of LMP + adding 7 days

1. Eg. LMP = 01.01.99, EDC = 08.10.99
2. LMP = 01.01.99
3. Minus 3 months = 01.10.99
4. Plus 7 days = 08.10.99 = EDC

• Wt: foetal growth shown in mother's wt
• BP: preeclampsia
• Urine - protein, sugar

1. Dipstix read after 1 minute
2. Spurious results - hyperdynamic circulation (proteinaceous discharge)
3. Reverse proteinuria - test midstream specimen
4. Early midstream urine better
5. Proteinuria present in preeclampsia

• If Pt seen for 1st time at clinic
• BP - Pt sitting, appropriate cuff (too small = artificially raise BP; to large = difficult to place stetho over brachial artery)

1. Ideal = covers 2/3 of Pt's arm
2. Take 4th Korotcoff sound instead of 5th (due to hyperdynamic circulation)
3. Not uncommon for 5th Korotcoff sound to disappear at 0 mmHg
4. If not rested, Pt to sit and rest before measurement

• Proteinuria - take in context

• Expose adequately (xiphisternum to pubic area)
• Cover pubic area
• Linea nigra: midline pigmentation
• Stretch marks (striae gravidarum)
• Any surgical scars? Prev C-section, ab/ gynae operation
• Small subumbilical scar - laparoscopic surgery (can be 5mm long)
• Foetal movt sometimes seen (absence - not significance)
• Contractions?
• Measure: symphysial fundal height (corresponding to gestation)

• Determine uterine fundus
• Symphysal-fundal ht - estimates size of foetus (also number of foetuses)
• From mid 2nd trimester, 1cm = 1 wk of gestation (1) Chinese = +/- 3cm (2) Caucasian = +/- 2cm

• Cephalic presentation - foetal head in lower ab
• Breech - foetal head near fundus

• Longitudinal, Transverse, Oblique
• Determine where foetal back is
• Foetal heartbeat hear at cephalic end of foetal back
• 110-150 bpm normal for foetus

• Occurs when largest diameter presenting part (suboccipital diameter) enters pelvic brim
• Divide foetal head into 5 parts
• If 2/5 palpable abdominally, foetus considered engaged
• Nulliparous woman should engage by week 34
• Multiparous woman may not engage until labour

• Polyhydramnios - cushioning effect on foetus; foetal heart may not be palpable
• Oligohydramnios - foetal heart easily palpable

• Foetal heart rate (listen either side of umbilicus)

• Placenta = whitish structure
• If placenta anterior, cannot feel foetal heartbeat
• Foetal heartbeat best felt at back of foetus

Video from 1970's!

1. Contractions
2. A Show: blood-stained jelly-like material from neck of uterus
3. Rupture of membranes: surrounding baby

1. Hx, review antenatal records
2. General health, pulse, BP, urine
3. Feels baby's position, listen heart rate
4. Feel cervix - dilatation
5. Enema/ suppository

3 stages

1. Dilatation of the cervix: cervix opens so baby's head can pass through
2. Delivery of baby from uterus through vagina to outside
3. Delivery of placenta

• Labour and delivery should be kept short
• For 1st baby, allow 10 hours for 1st stage (mean = 5 hr), 60 minutes for 2nd stage, few minutes for 3^rd
• Labour = one of the few conditions when person can be admitted to hosp on own Dx
• Progress on labour chart (partogram)

1. Dilatation of cervix (closed - fully opened = 10cm)
2. Descent of baby's head through mother's pelvis (what % felt above pelvic brim)
3. Drugs - uterine stimulation, pain relief
4. Line across chart - dilatation of 1cm per hour (minimum rate) - if slower than this, should be sped up/ enhanced

1. Mother: can state how she feels, pulse, BP readily accessible
2. Baby: heart rate (foetal stetho, cardiotocograph)

1. Routine? Benefits on labour, quantity/ quality of amniotic fluid can be assessed
2. Forceps along fingers into cervix, forceps nip the membrane (torn by pulling downward with forceps)
3. Fluid - slightly pink
4. If no further movt in baby, oxytocin infusion

• Oxytocin infusion

1. Must not restrict mother
2. Forearm above wrist ideal location
3. Drip chamber/ automatic infusion pump
4. Dose gradually increased but never exceed 40 milliunits/ minute
5. This can be used to induce labour
6. Primagravid woman: cervix may be too long/ tight for membrane rupture
7. Can insert self-retaining catheter into extraamniotic space and inject oestrogen/ prostaglandin - takes 12 hours - then induction can be performed

• Husband/ close friend during all 3 stages
• Staff allocated to woman (eg. Doctor, midwife) to stay during whole labour

1. Injection - eg. Pethidine (injection into buttock, moderately effective, Pt comfortable and drowsy, give small amount frequently rather than large amount infrequently, rare for > 2 injections to be needed)
2. Inhalation - eg. Gas (NO), oxygen (50:50 NO:O2, stored in cylinder, woman taught to use in antenatal class, self-operated, breath just before/ during contraction, no risk of overdose (valve requires suction for delivery)
3. Regional block - eg. Lumbar epidural (if not enough pain relief, LA to dumb skin, needle introduced between 2 vertebrae, cannula threaded into epidural space, needle pulled back leaving cannula in place (strapped to skin) - eg. Marcaine: absorbed by nerve roots, stop transmitting pain for 2 hours, motor function minimally affected

• IV infusion set-up
• Woman on tiltable bed, spine flexed, lying on side
• Skin painted with antiseptic and draped with sterile towels
• Inject LA to numb skin
• 2A needle introduced between 2 lumbar vertebrae, between ligaments, loss of resistance shows placement in epidural space
• Air injected without resistance to confirm correct placement (if injected too far, air pushes fluid out) - do not proceed with procedure
• Catheter introduced and needle withdrawn
• Sterile dressing over catheter, which is strapped to woman's back
• Bupivocaine commonly used - lasts 2 hours
• Repeat doses/ top-ups can be give once effect wears off
• S/E: decreased BP (must record every 5 minutes)
• If too low: woman tilted head down on side, IV fluid 1 L introduced

• Presentation: 97% cephalic, 3% breech/ transverse
• Cervix admits one finger
• Baby's head engaged in pelvic brim
• Vertex presentation in left occipitolateral position

Early labour

• Head begins to descend; undergone rotation to occipitoanterior position

1^st stage labour

• Head descended; internal rotation proceeding (due to baby's head reaching levator ani; flexes and rotates head to fit outlet)
• Late 1^st stage - cervix 3/4 dilated; internal rotation complete; head below ischial spines; occipitoanterior position

2nd stage labour

3^rd stage of labour

• DO NOT pull placental cord out (1) Umbilical cord separates, placenta remains inside uterus, needs operation (2) Acute inversion of uterus - obstetrics emergency
• How to know placenta has separated

1. Gush of blood comes out
2. Lengthening of umbilical cord
3. Uterus pushed up a little

• Designed to act as cradle protecting baby's head while allowing Dr to reinforce while mother pushes
• Minor variation of normal delivery
• Usu. head of baby rotated to occipitoanterior position (may need to be done by obstetrician)
• Block/ epidural
• Vaginal exam - to see if forceps delivery possible
• 1st blade around baby's head + guided into place by Dr's hand
• 2nd blade applied in similar way
• Gentle traction to bring head down to vulva, direction of pull follows curve of birth canal
• Vaginal tissues become stretched so perform episiotomy
• Baby's head born easily, rest of delivery proceeds normally

• When problems in 1st stage of labour when quick vaginal delivery not feasible
• Planned: if Dr anticipates problems (eg. Afterbirth situation low down, baby in wrong position, one twin growing poorly and would not withstand labour)
• GA or epidural
• Incision just above hairline on abdomen
• Indications in 1^st stage of labour: meconium liquor, slow progression, foetal heart abnormalities
• Indications in 2^nd stage labour (rare): baby's head not low enough for instrumentation, placental separation, baby's head too big
• Note: if reached 2^nd stage, 99% babies can be born vag delivery (but may tear, # head/ neck, baby dead)

• Buttocks/ feet first
• Greater risk to baby than head-first delivery
• If baby upset, C-section preferred
• If mother and baby healthy, normal vag delivery

• Oxytocin to enhance contractions to expel placenta
• Mother to push out placenta herself
• OR
• Midwife pull gently on cord while supporting uterus
• This stage the main cause of death (XS bleeding)

Failure of placenta delivery

• remove by reaching with free hand into uterus and dissecting it from uterine wall (GA, epidural)

XS blood loss

• Retention of all/ part of placenta + membranes
• Failure of uterus to contract properly - ergometrin or oxytocin
• IV infusion needed as bleeding can be catastrophic
• Check Pt does not have full UB (impedes exit of placenta)

• Distension of the lower part of the vagina evokes reflexes which stimulate the urge to push
• Pushing is achieved by the Valsalva response and contraction of diaphragmatic and ab muscles
• The head stretched the vagina and vulva as it delivers
• Extension occurs one the head passes beneath the symphysis pubis
• Foetal membranes usually rupture before this stage

• Shoulders deliver assisted by lateral flexion of the body
• Once this is achieved, the rest of the foetus delivers readily as the uterus contracts down