Obstetrics Flashcards
1st trimester
0-13 weeks
2nd trimester
14-28 weeks
3rd trimester
29-40 weeks
What does a urinary pregnancy test detect?
beta HCG levels
Where does fertilisation occur?
Fallopian tubes
Where does the blastocyst implant?
Uterine wall
Causes of early pregnancy bleeding (<12 weeks)?
Implantation bleeding Miscarriage Ectopic/Molar Chorionic haematoma Cervical (infection, cancer, polyp) Vaginal (infection)
How common is early pregnancy bleeding?
20%
Symptoms of a miscarriage?
Bleeding, cramping
Investigation of miscarriage?
USS, speculum exam
What does a closed os mean in miscarriage?
Threatened miscarriage
What does an open os mean in miscarriage?
Inevitable miscarriage
What causes cervical shock?
Incomplete miscarriage, products still left in cervix
Symptoms of cervical shock?
Cramps, N+V, sweating, fainting
Causes of miscarriage?
Embryonic abnormality e.g. chromosomal APS Infections- CMV, Rubella, Listeria Iatrogenic (after CVS) Emotional upset
What is early foetal demise?
Pregnancy in-situ but no heartbeat
What is anembryonic pregnancy?
No feotus (lack of development/reabsorbed)
Management of miscarriage?
Conservative- allow natural expulsion OR Medical induce expulsion OR Surgical removal
Causes of recurrent miscarriage?
APS Thrombophilia Balanced translocation Uterine abnormality Age of mother
Where is the most common location of ectopic pregnancy?
Ampulla
Symptoms and signs of ectopic pregnancy?
Pain + shoulder tip pain, bleeding, dizziness, collapse, SOB, N+V, pallor, peritonism, guarding
Investigations of ectopic?
FBC, group and save, bHCG, USS
What is pregnancy of unknown location (PUL)?
+ve pregnancy test but no sign of intrauterine or ectopic pregnancy
Management of ectopic or molar pregnancy?
Surgery if acutely unwell
Methotrexate
What is a molar pregnancy?
Non-viable fertilised egg- leads to an overgrowth of placental tissue
What is the appearance of molar pregnancy on ultrasound?
“snow storm”
What is a complete molar pregnancy?
Egg without DNA with 1/2 sperm
What is partial molar pregnancy?
Egg with 2 sperm
What kind of foetus results from complete molar pregnancy?
Diploid
What kind of foetus results from partial molar pregnancy?
Triploidy
Symptoms of molar pregnancy?
Hyperemesis (due to high bHCG), bleeding, SOB
When does implantation bleeding occur?
~10 days after ovulation
What is a chorionic haematoma?
Pooling of blood between endometrium and embryo
Uses of intra-uterine insemination?
Sexual problems, same-sex couples, BBV
Uses of IVF?
Pelvic disease, anovulatory infertility, unexplained
How long does an IVF cycle take?
6 weeks
Steps of IVF?
- Down regulation of ovulation (GnRH)
- Ovarian Stimulation (FSH + LH)
- Oocyte collection
- Fertilisation
- Embryo Transfer
What does ICSI stand for?
Intra-cytoplasmic Sperm Injection
Uses of ICSI?
Male infertility
Failed IVF
Complications of assisted conception?
Ovarian Hyperstimulation
Multiple Pregnancy
Ectopic Pregnancy
Miscarriage
Define hyperemesis gravidarum (HG)?
Excessive, protracted vomiting- decreasing quality of life (usually just 1st trimester)
Other complication of HG?
Dehydration, ketosis, electrolyte imbalance, weight loss, malnutrition, depression, altered LFTs
Management of HG?
Rehydrate + electrolyte replacement Parenteral anti-emetics (cyclizine) Nutritional supplement Thiamine supplement Steroids if SEVERE
What does the placenta secrete to maintain corpus luteum (maintain progesterone levles)?
HCG
At how many weeks can the external genitalia be seen on USS?
16 weeks
Where does spermatogenesis occur?
Seminiferous tubules
mature on inside and burrow to outside
Where is sperm stored?
Epididymis
Which cells produce testosterone and which hormone controls this?
Leydig cells
LH
What does blood fill to produce an erection and which muscles contract?
Corpora cavernosa
Accessory sex glands and urtheral + erectile muscles
Causes of male infertility?
CF, vasectomy, undescended testes, chlamydia, chemo/radiotherapy, tumours, Klinefelters (XXY), tubal abnormalities, CAH, steroid abuse, pituitary tumours etc.
Investigations of male infertility?
Sperm analysis (3 days abstinence) Endocrine profile Chromosome analysis CF screening STI screening Scrotal scan
Treatment of male infertility?
Reversal of vasectomy
ICSI
Sperm aspiration
Donor sperm insemination
Abortion act- who needs to sign?
2 registered medical practitioners
In Tayside, you can get an abortion up to…?
18 weeks + 6 days
When is conscientious objection to abortion not valid?
Emergency situations
Until how many weeks can you have an abortion if there are foetal abnormalities?
Term
What is the most common approach to treatment of psychosexual dysfunction?
Psychodynamic psychotherapy
How long can sperm live in vagina for?
5 days
How long can the ovum live in the vagina?
up to 24 hours
Name for methods of “natural family planning”
Basal body temp (slight increase= ovulation)
Cervical mucus
Cervical position
“Standard days”
How can breastfeeding act as a form of contraception?
Lactational amenorrea:
Exclusive breastfeeding, <6 months postnatal and amenorrhea
2 medical steps for TOP?
- Mifepristone 200mg
24-48 hours later - Misoprostol
What kind of medication is mifepristone?
Anti-progesterone
What kind of medication is misoprostol?
Prostaglandin
What happens after misoprostol is taken?
4-6 hours later, womb lining breaks down and womb contracts
What are the surgical options for TOP?
Vacuum aspiration
Dilatation and evacuation
When can vacuum aspiration take place?
6-12 weeks
When can dilatation and evacuation take place?
13-24 weeks
Which contraceptives CANNOT be started straight away after TOP?
Depo injection
Vaginal ring
What does foetal malnutrition lead to?
Insulin resistant + impaired glucose tolerance- T2DM
Risks of overweight to mother?
Miscarriage
Gestational diabetes
Pre-eclampsia
Still birth
Risks of overweight to baby?
Macrosomia
Congenital anomalies
Increased weight
How many extra calories are needed during pregancy?
300 kcal
How many extra calories are needed for breastfeeding?
640 kcal
What supplements are given during pregnancy, and how much?
Folic acid- 400 micrograms (pre- 12 weeks) (5mg if high risk)
Vitamin D- 10mg (pregnancy + breastfeeding)
Iron- if high risk of anaemia
Foods to avoid in pregnancy?
Soft cheese Tuna Raw/partial eggs Pate Liver Undercooked meat, game, cured meat
Which pregnancy hormone causes mammary gland enlargement and prepares for lactation?
Prolactin
What is a molar pregnancy at risk of becoming, and which type has a bigger risk?
Choriocarcinoma
Complete molar
How do you work out due date?
Add 9 months + 7 days to first day of last period
Important parts of booking visit of antenatal care?
BMI BP Urinalysis USS Mental health screen Test for trisomy, sickle cell + thalassemias
How is gestation determined on USS?
Crown-rump length Head circumference (>14 weeks)
When is USS carried out to test for foetal anomalies?
20 weeks
What is looked for in a foetal anomalies screen?
Trisomy Cleft palate Neural tube defects Abdominal wall Limb deformities Placental health
How is Down’s Syndrome screened for and when?
Nuchal thickness/translucency (11-13 wks)
Bloods- HCG + AFP (15-20 wks)
Amniocentesis (15 wks) or CVS (12 wks)
(also NIPT)
When is anti-D given to Rhesus negative mothers, and how much?
500 units IM
at 28 weeks or after a sensitising event (surgical evacuation, miscarriage, CVS/amio, delivery)
When is the dating USS in pregnancy?
10-16 weeks
What is Non-Invasive Prenatal testing (NITP) used for and how does it work?
Testing for trisomy and sex determination (e.g. X linked conditions)
Tests for free foetal DNA in maternal blood (ratio normal or abnormal?)
When might NITP cause a false positive?
Maternal cancers
When does the placenta become functional?
Week 5
What does the placenta secrete to maintain progesterone secretion?
human chorionic gondotropin (hCG)
Oxygen diffuses from mother to foetus via..?
Umbilical blood
Foetal oxygenated blood returns to foetus via..?
Umbilical VEIN
Foetal de-oxygenated blood returns to placenta via..?
Umbilical ARTERY
Urinary adaptations in pregnancy? (2)
Increased GFR
Increased renal plasma flow
What does the placenta release that leads to hypertension, insulin resistance and gestational diabetes?
CRH- corticotropin-releasing hormone
Definition of small for dates (SGA) pregnancy?
Estimated fetal weight/fetal abdominal circumference is <10th centile
Haematological adaptations in pregnancy? (2)
Increased plasma volume
Increased RBCs (erythropoeisis)
Haemoglobin reduced by dilution
Respiratory adaptations in pregnancy? (3)
Increased RR
Increased tidal volume
Increased O2 consumption
Risk factors for SGA pregnancy?
>40 BMI >35 Cocaine, smoking Previous stillbirth Hypertension Diabetes Renal impairment APS
Causes of small for dates pregnancy?
Constitutionally small
IUGR- intra-uterine growth restriction
Causes of preterm delivery?
Infection- UTI, appendicitis, pneumonia Multiple pregnancy Polyhydramnios Placental abruption Idiopathic
IUGR can be symmetrical or asymmetrical. What causes each?
Symmetrical- chromosomal
Asymmetrical- placental problems (normal head, small abdomen)
IUGR can be symmetrical or asymmetrical. What causes each?
Symmetrical- chromosomal
Asymmetrical- placental problems (normal head, small abdomen)
Causes of SGA pregnancy?
Maternal risk factors
Placental infarcts or abruption
Foetal infection- rubella, CMV
Chromosomal
What is IUGR- intra-uterine growth restriction?
Failure to achieve growth potential (crossing centiles of growth in uterus)
Causes of large for dates pregnancy?
Wrong dates Macrosomia Polyhydramnios Multiple Pregnancy Diabetes in pregnancy
Features of IUGR?
Decreased fundal height, liquor and fetal movements
Investigations of IUGR?
USS
CTG
Umbilical artery doppler
Management of IUGR?
37 week delivery, consider C-section
Steroids during delivery
Magnesium sulphate- foetal neuroprotection
Definition of large for dates pregnancy?
Symphyseal-fundal height >2cm for gestational age
Definition of macrosomia?
Estimated foetal weight >90th centile