Year 3 MBChB
Clinical Skills Session
Obstetric Examination
Authors:
The Clinical Skills Lecturer Team
Reviewed & ratified by:
Dr Andrew Sharp 2019
Obstetrics and Gynaecology Lead
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Obstetric Examination
Learning objectives
To revise anatomy and physiology of reproductive system
To link anatomy and physiology to practical skill
To understand reasons for undertaking obstetric examination
To be able to carry out obstetric examination
Anatomy of the female reproductive system (relating to Obstetric Examination).
The normal uterus lays within the pelvis posterior to the bladder amd anterior to the rectum. The uterus has an
anterior position in relation to the vagina with slight anterior flexion and is termed to be ante-verted and ante-
flexed.
Pelvis and perineum
Smith, Claire F., BSc (Hons) PGCE PhD SFHEA FAS FLF, Gray’s Surface Anatomy and Ultrasound, 4, 50-64 Copyright ©
2018 © 2018, Elsevier Limited. All rights reserved.
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As the duration of the pregnancy continues, the uterus increases in size to accommodate the developing fetus.
Placenta and Fetal Membranes
Moore, Keith L., BA, MSc, PhD, DSc (OSU), DSc (WU), FIAC, FRSM, FAAA, Developing Human, The, Chapter 7, 107-
139.e1 Copyright © 2016 Copyright © 2016 by Elsevier, Inc. All rights reserved.
The anatomy of the female pelvis is relevant to this examination; as measurement of the fundal height,
determination of the fetal position and fetal engagement are described in relation to the pelvis.
Anatomy of the female pelvis
de Costa, Caroline, Essential Obstetrics and Gynaecology, Chapter1, 3-11 Copyright © 2013 Elsevier Ltd. All rights
reserved.
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The obstetric examination
Often when a woman discovers she is pregnant she will book an appointment via her GP practice or the hospital
directly to see a midwife. The booking appointment is an initial contact with a midwife at 8 – 12 weeks gestation.
Initial meeting with a health care practitioner usually includes:
Take the patient’s obstetric history to include LMP (to calculate gestation), previous pregnancies, medical, surgical,
medication, social and family histories.
Measure height and weight
Record the blood pressure
Obtain a urine sample (MSSU) screening for asymptomatic bacteriuria. The identification and treatment of
asymptomatic bacteriuria reduces the risk of pyelonephritis, proteinuria and glycosuria.
Provide advice and literature on supplements / lifestyle changes beneficial to the pregnant woman.
Pregnancy multivitamins usually include:
Folic Acid (dose 400mcg)
Vitamin D throughout pregnancy and whilst breast feeding,
Vitamin C,
Calcium,
Dietary advice will be offered including on Iron supplementation (if required),
See this NHS page for more information:
https://www.nhs.uk/conditions/pregnancy-and-baby/pages/vitamins-minerals-supplements-pregnant.aspx#Iron
Lifestyle advice on food hygiene, including how to reduce the risk of a food acquired infection.
Lifestyle advice, including smoking cessation, the implications of recreational drug use and alcohol consumption in
pregnancy
Other advice may include:
Wear gloves when handling soil or gardening.
Avoid cat faeces in cat litter or soil.
Avoid alcohol during the pregnancy (increased risk of miscarriage)
Avoid smoking (risk of low birth weight and preterm birth). If a woman wants nicotine replacement therapy is offered
as standard.
Advice on available antenatal screening as well as discussing risks and benefits – these are usually arranged at the
booking appointment and include screening for common aneupolidy’s such as Trisomy 21 (Down syndrome)
Please see NICE guidelines on “Antenatal care for uncomplicated pregnancies”
https://www.nice.org.uk/guidance/cg62
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At booking appointment
Women requiring additional care may be identified (domestic violence, safeguarding issues, vulnerable women,
communication difficulties, drug alcohol dependency and age of patient including subsequent associated risks)
Bloods are taken for grouping and rhesus D status are checked
Screening for haemoglobinopathies, anaemia, red-cell alloantibodies, hepatitis B virus, HIV, rubella susceptibility and
syphilis are offered.
Repeat screening for asymptomatic bacteriuria.
Pregnant women younger than 25 years are advised about the high prevalence of chlamydia infection in their age
group, and give details of the National Chlamydia Screening Programme.
Screening for Down's syndrome is offered.
Early ultrasound scan for gestational age assessment
Height, weight and calculate body mass index are measured.
Blood pressure is measured and urine tested for proteinuria
Screening for gestational diabetes and pre‑eclampsia using risk factors is offered.
Women who have had genital mutilation are identified.
Past or present severe mental illness or psychiatric treatment are discussed as well as mood to identify possible
depression.
Calculating gestation – always uses 1st day of LMP
Naegele's rule – LMP + 1 year + 7 days - 3 months
Parikh's formula – LMP + 9 months - 21 days + cycle days
LMP + 280 days
Or use a gestational calculator
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Appointment Schedule for Uncomplicated Pregnancy.
For nulliparous patients with an uncomplicated the routine number of appointments is 10.
For parous patients with an uncomplicated pregnancy the routine number of appointments is 7.
Gestational Age
Appointment
<10 weeks
Booking Appointment + 10-14 weeks USS for
gestational age and to detect multiple pregnancies
16 weeks
Review, discuss and record the results of all screening
tests undertaken.
Investigate a haemoglobin level below 11 g/100 ml
and consider iron supplementation if indicated.
Measure blood pressure and test urine for
proteinuria.
18-20 weeks
USS for structural abnormalities.
If the placenta is found to extend across the cervical
os, scan is repeated at 32 and 36 weeks and possibly
a transvaginal USS.
25 weeks
Measure and plot symphysis–fundal height.
Measure blood pressure and test urine for
proteinuria.
28 weeks
Offer a second screening for anaemia and atypical
red‑cell alloantibodies.
Investigate a haemoglobin level below 10.5 g/100 ml
and consider iron supplementation, if indicated.
Offer anti‑D prophylaxis to rhesus‑negative women.
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Measure blood pressure and test urine for
proteinuria.
Measure and plot symphysis–fundal height.
31 weeks
Measure blood pressure and test urine for
proteinuria
Measure and plot symphysis–fundal height
34 weeks
Offer a second dose of anti‑D to rhesus‑negative
women
Measure blood pressure and test urine for
proteinuria
Measure and plot symphysis–fundal height
Review, discuss and record the results of screening
tests undertaken at 28 weeks
36 weeks
Measure blood pressure and test urine for
proteinuria.
Measure and plot symphysis–fundal height.
Check position of baby.
For women whose babies are in the breech
presentation, offer external cephalic version (ECV).
38 weeks
Measurement of blood pressure and urine testing for
proteinuria.
Measurement and plotting of symphysis–fundal
height.
40 weeks
Measurement of blood pressure and urine testing for
proteinuria.
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Measurement and plotting of symphysis–fundal
height.
41 weeks
A membrane sweep should be offered.
Induction of labour should be offered.
Blood pressure should be measured and urine tested
for proteinuria.
Symphysis–fundal height should be measured and
plotted.
Please read the NICE guidelines regarding pregnancy.
https://pathways.nice.org.uk/pathways/antenatal-care-for-uncomplicated-pregnancies
Obstetric History
The level of detail included in an obstetric history may change as the pregnancy develops.
Presenting complaint This may be that a woman has completed a home pregnancy test and has a positive result. Some women may present with amenorrhea whilst actively trying to conceive. History of presenting complaint Date (if known) of positive pregnancy test Date of last menstrual period Any other symptoms? Nausea and vomiting of pregnancy (morning sickness). What (if any) confirmatory tests of gestational age (e.g. ultrasound) Prenatal screening tests. When and whether performed/ declined and results. Fetal movements (may also give a clue to position of fetus) Past obstetric history, to include: History of past pregnancies to include dates and number of pregnancies (Gravidy);
The term "gravida" can be used to refer to a pregnant woman. A "nulligravida" is a woman who has never been pregnant. A "primigravida" is a woman who is pregnant for the first time or has been pregnant one time. A "multigravida" or "secundigravida" is a woman who has been pregnant more than one time.
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Outcome (Parity, fetus carried to 24 weeks plus (viable gestational age (includes live and still births))). A woman who has never carried a pregnancy to 24 weeks is nulliparous and called a nullipara or para 0. A woman who has given birth once before is primiparous, and is called a primipara, primip or para 1. A woman who has given birth two or more times is multiparous and is called a multip. A woman who has given birth five or more times is a grand multipara. And finally a woman who has given birth seven times or more is a great grand multipara. Gestation at end of pregnancies Mode of delivery – spontaneous vaginal delivery (SVD), lower uterine segment caesarean section. Sex, weight and status of baby (live or still birth) Mode of feeding (breast or bottle) Current information on child (development, illness, etc.) Complications of pregnancy (diabetes, pre- eclampsia, etc.) Information on the mode of conception (if assisted conception) Information on the father of the child The obstetric history will also include all routine history sections Past Medical History, Medication History, Family History, Social History etc.
Obstetric Examination
Explain to the patient that you would like to examine them, including their abdomen, and the position of their baby.
Provide a lot of reassurance that it will be a gentle examination.
Urinalysis is part of an obstetric examination, ask the patient to void their bladder before the physical examination
and obtain an MSSU.
Offer to have a chaperone present, ensure the room is warm and well lit, preferably with a mobile light source.
It is standard practice to start with the cardiovascular and respiratory systems, this gains a measure of the patient’s
general health.
I – FLiPPER is a useful acronym to use for this examination.
Inspection – Fundal height – fetal Lie – fetal Presentation
fetal Position – fetal Engagement – fetal heart Rate
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Inspection
General inspection
As always, begin with general inspection of the patient.
Comfortable at rest? Breathlessness and / or Pallor?
Chloasma (increased pigmentation in face) or facial oedema?
Jaundice? Rare but may have serious consequences. Investigate
Anaemia?
Swelling, oedema or varicose veins in the legs?
Measure weight and height.
Examine the cardiovascular and the respiratory systems in turn, including measurement of blood pressure.
Specific abdominal inspection
Shape (symmetry) of the abdomen (ovoid)?
Size of the abdomen?
Scars, supra pubic (Pfannenstiel) scar?
Cutaneous signs of pregnancy such as; Linea nigra (line of dark pigmentation), red stretch marks of current
pregnancy (striae gravidarum) or silver white stretch marks (striae albicans) from previous pregnancy. Fetal
movements? Contractions of uterus / abdominal wall?
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Palpation
Before palpating the abdomen offer the patient the opportunity to empty their bladder to reduce discomfort and
prevent erroneous measurements, always enquire about any areas of tenderness and examine those areas last.
Fundal Height, also known as symphysis fundal height (Uterine Size) requires a tape measure.
The distance from the symphysis pubis to the upper edge of the uterus provides an estimation gestational age and
is objectively measured in centimeters. However, babies will vary depending on the size of the parents, for example
typically European babies are bigger than Asian babies. Customized charts are generated taking into account the
ethnicity, weight and height of mum as well as how many babies she has had in the past. An individualized growth
chart is then produced and stored within the antenatal notes.
The uterus first becomes palpable at approximately 12 weeks gestation.
To measure Symphysis Fundal Height (SFH)
Use the ulnar border if the left hand to press into the abdomen just below the sternum.
Move the hand down the abdomen in small steps until you can feel the fundus of the uterus. Place the zero point
of the tape measure face down on this central point. Move your other hand with the tape down the abdomen.
Locate the upper border of the symphysis pubis by palpating downward in the midline.
Measure the distance between the two points you have found in centimeters using a flexible tape measure.
Then check the measurements against the woman’s customized or population chart in the antenatal notes. To
determine if the baby is bigger or smaller than expected. This chart is bespoke to the mother, an example GROW
(Gestational Related Optimal Weight) chart is below, this allows fundal height measurements to be documented
and plotted against an expected growth pattern which is individual to the mother. This tool alerts clinicians to
disturbances in fetal growth, indicating the need for referral for a detailed ultrasound and assessment when the
fundal height deviates from the predicated centile indicating a fetus may be small for gestational age (SGA) or large
for gestational age (LGA).
X
X X
X
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Notice when measuring the fundal height; the measuring scale is not visible to prevent subjective bias.
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For the next few parts of the examination you will actively palpate for the fetus. The contents of the uterus are
non-compressible therefore firm controlled pressure is required to feel through the uterine wall and displace the
amniotic fluid in order to feel the fetus. This requires practice and experience to develop. Ensure you watch the
mother’s face to ensure no undue pressure is applied.
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Fetal Lie
This is the relationship between the long axis (spinal column) of the fetus and the long axis of the uterus.
The lie can be described as:
Longitudinal - the long axis of the fetus matches the long axis of the uterus, the presenting part will be palpable
towards the pelvis.
Transverse - the fetus lies at right angles to the uterus and the fetal poles are palpable in the flanks.
Oblique - the long axis of the fetus lies at an angle of 45 degrees to the long axis of the uterus, the presenting
part will be palpable in one of the iliac fossa.
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A longitudinal lie
The blue curve lies along the spine (long axis)
of the fetus.
The yellow dashed line represents
The long axis of the uterus (allowing
for image rotation).
The best position to palpate the fetal lie is to stand on the mother’s right side.
Put your left hand along the left side of the uterus and your right hand on the right side of the uterus.
Palpate towards the midline with one and then the other hand. The fetal back will be felt as firm resistance or the
limbs as an irregular shape.
Palpate more widely, attempt to locate the head and the breech. The head can be felt as a smooth, round object
that is gently ballotable between your hands. The breech (buttocks) is softer, less discreet, and may not be
ballotable.
Fetal Presentation This is the part of the fetus that presents to the mother’s pelvis. Possible presenting parts include:
Cephalic presentation in the longitudinal line.
Breech presentation in the longitudinal line.
A fetus in an oblique or transverse lie cannot engage.
Stand at the mother’s right side, facing her feet.
Place both hands on either side of the lower part of the uterus.
Bring the hands together firmly but gently, you should be able to feel either the head, breech, or other
body part such as the shoulder.
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It is possible for the fetus to present face first and this would be described as a face or brow presentation. If the fetus is breech with an extended leg presenting below the breech such as into the vagina the term as footling may be applied. If the fetal lie is oblique then you may hear the term shoulder presentation. Fetal Position The position of the fetus is the relationship of the fetal OCCIPUT in cephalic (vertex) presentation the SACRUM in breech presentation or the MENTUM (chin) in a face / brow presentation and the pelvis of the mother. The OCCIPUT, SACRUM or MENTUM are assumed to be in line with the spine (long axis) of the fetus.
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In the picture series below you can see a representation of all the possible fetal positions relating to a cephalic presentation (the blue arrow indicates the occiput of the fetus).
Modified from Häggström, Mikael (2014). "Medical gallery of Mikael Häggström 2014". Breech presentations follow the same pattern using the fetal sacrum and Sacro as the descriptor. i.e. Right Sacro Transverse/Lateral Face or brow presentations follow the same pattern using the fetal chin and Mento as the descriptor. i.e. Left Mento Transverse/Lateral Engangement When the widest part of the skull is within the pelvic inlet at the pelvic brim, the fetal head is said to be engaged.
Anterior
Right Left
Posterior
Direct Occipito Anterior
Direct Occipito Posterior
Right Occipito Anterior Left Occipito Anterior
Left Occipito Transverse/Lateral
Left Occipito Posterior Right Occipito Posterior
Right Occipito Transverse/Lateral Orientation of mother’s pelvis
Pubis
Sacrum
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In the cephalic (vertex) presentation, palpation of the head is assessed and expressed as the number of fifths of the
skull palpable above the pelvic brim. A fifth is roughly equal to a finger breath.
The head is engaged when 3 or more fifths are within the pelvic inlet - so 2 or fewer fifths are palpable.
Fetal Heart Rate
The fetal heart rate would normally be in the range of 110 – 160 beats per minute.
Pelvic brim
True pelvis
False pelvis above the
encircled area
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It is normally best heard over the shoulder of the fetus, if this can be identified.
There are a number of devices to assist you to hear the fetal heart;
Pinard horn or stethoscope (fetoscope): Allows the examiner alone to hear the fetal heart sounds. Sometimes used
prior to the SonicAid or Fetal Doppler if the gestational development is thought to be abnormal.
SonicAid or fetal Doppler: Electronic device allows parent(s) to hear, may be more comfortable to use.
When using the Pinard or SonicAid the examiner should count the fetal heart for a full minute and simultaneously
take the maternal pulse to ensure it is the fetal heart being listened to rather than maternal or placental blood
flow.
Cardiotocography allows fetal heart to be recorded and contractions to allow assessment of fetal wellbeing during
labour.
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Useful Links
https://www.nice.org.uk/guidance/conditions-and-diseases/fertility--pregnancy-and-childbirth
Reference
Oxford Handbook of Clinical Examination and Practical Skills, 2nd Edition. Thomas & Monaghan, Oxford Medical
Publications, University Press.
Indications for Obstetric Examination
Obstetric examination may be carried out during the normal antenatal screening programme which all pregnant
women in the UK are offered.
An overview of the programme can be found by following this link - https://www.nhs.uk/conditions/pregnancy-
and-baby/antenatal-appointment-schedule/.
In addition to these “routine” appointments obstetric examination may be performed if the pregnant lady is unwell
or there are concerns about the health of the fetus.