Pregnancy Flashcards
- what is the role of the folicular phase?
2. what is the role of the luteal phase?
- support gamete maturation
2. support pregancy
Where does fertilisation take place?
ampulalry ithmic junction of the fallopian tube
- how long can sperm survive in the reproductive tract for?
2. how long can eggs survive after fertilisation?
- ~5 days
2. 24 hours
Name 3 things that assist the travel of sperm through the female reproductive tract
- motility of sperm
- uterine/oviduct contractions
- cilliated oviduct epithelia
- what process do sperm need to go through before they can fertilise the egg?
- name changes in the sperm that occur during this process (2)
- What is this process largely dependent on?
- capacitation
- activation of whiplash tail
acrosome reaction - calcium
- what triggers the acrosome reaction?
- What occurs during the acrosome reaction?
- What is the consequence of the acrosome reaction?
- sperm interraction with glycoproteins ZP2/3 on the zona pellucida
- release of hyaluronidase to digest the cumulus (surrounds the egg)
- sperm are able to penetrate and fertilise the egg
- What intracellular ion increases following sperm fusion with the egg?
- Does this increase occur synchronously or as a wave?
- What is this activity triggered by?
- calcium
- as a wave across the egg, starting from the point of sperm entry
- spermatozoa phospholipase C-zeta, which passes into the oocyte following fusion
ESTABLISHING DIPLOIDY
- what is block to polyspermy?
- How is it achieved?
- what is the role of CSF and MPF?
- How is oocyte meiosis resumed?
- Is the second meiotic division of the oocyte equal or unequal?
- prevention of further sperm fusing with the egg, in order to prevent polyploidy
- elevated calcium levels result in the mobilisation and fusion of cortical granules within the oocyte plasma membrane which act on the zona pellucida to prevent further binding and penetration by sperm
- MPF stabilises meiotic metaphase (in which oocytes are arrested); CSF stabilises MPF
- Rise in calcium inhibits CSF, and destabilises MPF. As a result the oocyte progresses through second meiotic division
- unequal - creates a second polar body via which the second set of sister chromatids is removed
- What is sygnamy?
- How does this occur?
- What follows immediately after sygnamy?
- the coming together of the gametic chromosomes
- sperm nuclear membrane breaks down
two sets of haploid chromosomes each become surrounded by membranes - pronuclei
Haploid DNA undergoes DNA replication
pronuclear membranes break down and the chromosomes assume their positions on the equator - cleavage
- what is polyspermic fertilisation?
- what is digynic fertilisation?
- What is parthenogenetic fertilisation?
- egg that has been fertilised by more than 1 sperm. 3 polar bodies
- triploidy due to error in meiosis. 2 polar bodies are derived from the oocyte
- activation of the oocyte by stimulus other than sperm. 1 polar body/haploidy
- How long does it take for a blastocyst to form?
- what occurs at the 4 cell stage?
- What is the name given to the embryo at the 8-16 cell stage? What is formed at this stage?
- Describe the cell layers of the blastocyst
- 5 days
- zygotic genome activation - genome wide demethylation, followed by remethylation according to extracellular influences
- morula
- trophoblast - outer cells
Inner cell mass
- what hormone is signalling presence to mother dependent on?
- what hormone does the blastocyst produce?
- what does this hormone act on?
- which hormone is essential for pregnancy maintenance?
- Which structures produce this hormone?
- How is this hormone maintained?
- oestrogen
- hCG
- acts on the endometrial epithelium and corpus luteum
- progesterone
- syncytiotrophoblast and corpus luteum
- hCG acts on the corpus luteum to increase progesterone output. Also synthesised by syncytiotrophoblast
What hormones do the following produce?
- foetus
- placenta
- androgens
2. oestrogens (by aromatisation of androgens produced by the foetus)
FORMATION OF MONOZYGOTIC TWINS What is the characteristics in terms of placenta (chorionic) and amnioitic units of the following events: 1. early embryo splitting 2. fused dichorionic 3. ICM split 4. Embryonic disc split 5. Incomplete split
- which of the following can lead to twin transfusion syndrome
- embryos split separatly, forming two dichorionic and diamniotic foetoplacental units
- monoamniotic (two amniotic sacs) but dichorionic (shared placentas that are fused)
- monoamniotic and monochorionic
- monochorionic and monoamniotic
- monoamniotic, monochorionic conjoined twins
- ICM split and embryonic disc split
Name 5 causes of inferility
- male infertility
- unexplained infertility
- Ovulatory disorder
- tubal disease
- endometriosis
IVF
1. how is ovarian hyperstimulation achieved?
- name the following three stages of IVF
- GnRH agonist is given, which suppresses the formation of FSH and LH so that multiple follicles can develop
once the follicles reach the FSH dependent stage, a high dose of FSH is administered to maintain the multiple follicles - aspirate ovarian follicles
- co-incubation
- embryo selection and transfer
Describe the following:
- PESA
- MESA
- TESE
- TESA
- pericutaneous epididymal sperm aspiration. Sperm are aspirated from the epididymis
- microepididymal sperm aspriation
- Testicular sperm extraction - sperm are extracted from the testes by removing a part of the testes
- Testicular sperm aspiration - sperm are aspirated from the testes
Name foetal development changes that occur during:
- first trimester
- second trimester
- third trimester
- fertilisation, implantation, organogenesis and placentation
- nervous system development, hair, change in proportions, pain sensation, spine straightens
- growth, fat deposition, brain growth, lung development
Name maternal changes that occur in the three trimesters
- weight gain and nausea
- placental growth, rising of uterus, hypervolaemia, cardiac remodelling, breast remodelling
- braxton hicks, tiredness, restricted breathing, lactation
- when is the beginning of pregnancy dated as?
- At what day does the blastocyst enter the uterus and begin implantation?
- what phases of the ovarian cycle and uterine cycle does implantation coincide with?
- first day of the last known mentstrual period
- 5/6
- luteal phase of ovarian cycle and secretory phase of uterine cycle
- name the 2 phases of initial attachment
- what must be removed before attachment can occur?
- what type of implantation occurs in humans?
- close oposition,
adherence of trophoblast to endometiral epithelia - zona pellucida
- INVASIVE
- what interdigiates with villi on uterine epithelium?
- which proteins on the uterine epithelia undergo alteration?
- What is the result of this alteration?
- villous trophoblasts
- anti-adhesion mucin glycoproteins - reduced expression by activation of specific protease enzymes
- Allpws the cells of the trophoblast to penetrate into the uterine stroma
- How does the embryo erode the endometrial epithelium?
- what is the structure formed by fusion of trophoblast cells calles?
- What are the spaces which form in this structure (2) called?
- Which maternal structures invade these spaces?
- trophoblastic processes project between the adjacent epithelial cells. They secrete proteases which erodes the endometrial epithelia
- syncytiotrophoblast
- lacunae
- spiral arteries
- Which hormone is involved in maternal recognition of an embryo?
- How does this hormone act?
- Which hormone(s) are responsible for causing the early symptoms of pregnancy
- How long is hormone (1) required to support the pregnancy?
- hGC
- signals to the corpus luteum to keep producing oestrogen and progesterone
- progesterone and oestrogen
- 8-10 weeks
- what is the chorion?
- Which structures make up the chorion?
- what is the amnion?
- which structures make up the amnion?
- What is the yolk sac?
- Which structures make up the yolk sac?
- Which structure is the precursor of the placenta?
- outer most membrane surrounding the embryo
- trophoblast and (extraembryonic) mesoderm
- membrane that closely covers the embryo and expands to form the amniotic sac
- ectoderm and mesoderm
- membranous sac attached to the embryo which undergoes obliteration
- endoderm and mesoderm
- chorion
- which structures form the primary chorionic villi?
- what forms the secondary chorionic villi?
- which forms the tertiary chorionic villi?
- describe the remodelling of the maternal spiral arteries
- which structures penetrate into the lacunae?
- What is formed by the fusion of lacunae?
- What is the role of this? (6)
- What prevents the mixing of blood?
- cytotrophoblast (layer underlying syncytiotrophoblast)
- they have finger like projections that penetrate and expand into the syncytium - growth of extraembryonic mesoderm into the primary chorionic villi
- formation of embryonic vessels on the secondary chorionic villi
- low resistance, high flow
- chorionic villi
- intervillous spaces
- trophoblast surrounding the villi
- What forms the foetal portion of the placenta?
2. What forms the maternal portion of the placenta?
- chorionic villi of the chorion
2. deducida basalis of the endometrium
- How many umbilical arteries and veins are there?
- What do these carry?
- Name 4 differences between maternal and foetal blood
- two arteries, one vein
- arteries - carry deoxygenated foetal blood to placenta
vein - carry oxygenated foetal blood to the foetus from intervillous spaces - lower PO2
- higher affinity for O2
- carriers more oxygen
- higher PCO2
- Name 3 cardiovascular changes that occurs in mother
- How does progesterone cause hypervolaemia?
- How does oestrogen cause hypervolaemia?
- does maternal BP change or remain the same
- increased HR and stroke vol
increased heart size
hypervolaemia > increased venous return - vasodilation, decreased peripheral resistance, increased aldosterone, increased thirst
- increased angiogenesis, blood glow, venous distensibility, angiotensin II, renal sodium and water reabsorption, aldosterone
- remain the same
Name 6 respiratory changes in the mother
- increased respiratory effort
- increased O2 consumption
- elevation of diaphragm and upward displacement of ribcage (reduction in residual volume)
- thoracic breathing
- lowered sensitivity to chemoreceptors
- increased responsiveness to PCO2 (under influence of progesterone, increases tidal vol)
name 7 renal and urinary changes in the mother
- enlarged kidneys
- displacement and enlargement of ureters
- decreased bladder tone
- reflux from bladder to ureters
- urinary stasis
- urine richer in glucose and amino acids
- increased risk of UTI
name the 4 types of planned birth settings
- home
- freestanding midwifery units
- alongside midwifery units
- obstetric units
what are the aims of antenatal care
- optimise maternal and foetal health
- develop a partnership between woman and health professional
- exchange info that promotes choice
- recognise deviations from the norm and refer appropriately
- increase understanding of public health issues
- provide opportunities to prepare for birth and parenthood
- When does NICE recommend the booking appointment is done by?
- what information is gathered during the booking interview? (8)
- 10 weeks
- demographic details
present pregnancy and menstrual history
previous pregnancies and births
medical Hx
surgical Hx
social and lifestyle Hx
family Hx
baseline observations
Define:
- gravida
2. para
- number of pregnancies
2. number of children
How many antenatal visits do the following women get:
- nulliparous
- parous
- 10 - booking, 16, 25, 28, 31, 34, 36, 38, 40 and 41
2. 7 - booking, 16, 28, 34, 36, 38, 40, 41
- What is examined during physical examination?
2. What screening tests are performed during antenatal visits?
1. weight blood pressure urinalysis oedema varicoses nausea and vomiting bladder and bowels blood tests
2. ABO blood group and Rh factor full blood count and Hb levels syphillis and hepatitis HIV antibodies rubella immune status specific blood tests for haemoglobinopathies Maternal Screening for Down's Syndrome 18-21 week structural anomaly scan
At what stage of pregnancy is palpation and auscultation of foetal heart recommended?
36 weeks
- Where is progesterone produced? (and at what times)
- What is the role of the foetus in pregnancy endocrinology?
- What is the role of the placenta in pregnancy endocrinology?
- in the corpus luteum up until 10 weeks; then in the placenta
- converts progestins made by the placenta into androgens (the placenta lacks the enzymes to do this)
- produces progesterone
aromatises androgens produced by the foetus into oestrogen