Fertility (IVF, infertility (male and female), ovarian hyperstimulation syndrome) Flashcards

1
Q

What are the normal chances of conceiving a child?

A

Statistically a couple stands an 80% chance of conceiving within 1 year if:

  1. The woman is <40yo
  2. They do not use contraception
  3. They have regular intercourse

The overall probability increases to 90% if considered over 2 years.

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2
Q

what are some factors affecting natural fertility?

A

Increasing age
Obesity
Smoking
Tight-fitting underwear (males)
Excessive alcohol consumption
Anabolic steroid use
Illicit drug use

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3
Q

When should investigation and referral be done for infertility?

A
  • should be initiated after the couple has been trying to conceive without success for 12 months
  • this can be reduced to 6 months if the woman is older than 35, as ovarian stores are likely to be reduced and time is precious
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4
Q

What are the causes of infertility?

A
  • Sperm problems (30%)
  • Ovulation problems (25%)
  • Tubal problems (15%)
  • Uterine problems (10%)
  • Unexplained (20%)

40% of infertile couples have a mix of male and female causes

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5
Q

What are some general advice for couples trying to get pregnant?

A
  • woman should be taking 400mcg folic acid daily
  • aim for a healthy BMI
  • avoid smoking and drinking ecessive alcohol
  • reduce stress as may negatively affect libido and relationship
  • aim for intercourse every 2-3 days
  • avoid timing intercourse

timed intercourse to coincide with ovulation is not reccomended as it just increases stress and pressure in relationship

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6
Q

What are the initial investigations for infertility?

A
  • BMI (low could indicate anovulation, high could indicate PCOS)
  • chlamydia screening
  • semen analysis
  • female hormonal testing
  • rubella immunity in the mother
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7
Q

What does female hormone testing involve?

A
  • serum LH and FSH on day 2-5 of cycle
  • serum progesterone on day 21 of cycle ( or 7 days before end of cycle)
  • anti-mullerian hormone
  • TFTs
  • prolactin (hyperprolactinaemia is a cause of anovulation) when symptoms of galactorrhea or amenorrhoea
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8
Q

What would high FSH suggest?

A

-poor ovarian reserve (number of follicles that women has left in ovaries)

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9
Q

What would high LH suggest?

A

-polycystic ovarian syndrome

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10
Q

What would high progesterone on day 21 suggest?

A

-ovulation has occured and the corpus luteum has formed and started secreting progesterone

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11
Q

Why is Anti-mullerian hormone measured?

A
  • can be measured at any time in the cycle and is the most accurate marker of ovarian reserve
  • it is released by granulosa cells in the follicles and falls as the eggs are depleted.
  • high level indicates a good ovarian reserve
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12
Q

What are the further investigation for infertility, often performed in secondary care?

A
  • pelvic US –> to look for polycystic ovaries or any structural abnormalities in the uterus
  • hysterosalpinogram –> to look at the patency of the fallopian tubes.
  • laparoscopy and dye test –> to look at the patency of the fallopian tubes, adhesions, and endometriosis
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13
Q

What is a hysterosalpingogram?

A
  • a type of scan used to assess the shape of the uterus and the patency of fallopian tubes
  • helps with diagnosis and has therapeutic benefit
  • increases rate of conception
  • tubal cannulation under xray guidance can be performed during this to open up tubes
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14
Q

How does a hysterosalpingogram work?

A
  • small tube is inserted into cervix and a contrast medium is injected through the tube and fills the uterine cavity and fallopian tubes
  • x-ray images are taken with contrast showing up outlining the uterus and tubes
  • if contrast does not fill a tube, it suggests tubul obstruction
  • as risk of infection with procedure, antibiotics are given prophylactically
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15
Q

What should be done before a hysterosalpingogram?

A

-screening for chlamydia and gonorrhoea

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16
Q

What does a laparoscopy and dye test involve?

A
  • pt admitted for laparoscopy, during procedure dye is injected into the uterus and should be seen entering the fallopian tubes and spilling out at the ends of the tubes
  • this will not me seen if there is tubal obstruction
  • during laparoscopy, surgeon can also assess for endometriosis or pelvic adhesions and treat these
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17
Q

What are the management options when anovulation is the cause of infertility?

A
  • weight loss for overweight pts with PCOS
  • clomifene may be used to stimulate ovulation
  • letrozole (aromatase inhibitor) may be used instead of clomifene
  • gonadotropins may be used to stimulate ovulation in women resistant to clomifene
  • ovarian drilling may be used in PCOS
  • meftormin may be used where there is insulin insensitivity and obesity
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18
Q

What is clomifene?

A
  • a selective oestrogen receptor modulator
  • given on days 2 to 6 of cycle
  • stops oestrogen negative feedback leading to higher GnRH and LH + FSH
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19
Q

What are the management options when tubal factors are the cause of infertility?

A

The options for women with alterations to the fallopian tubes that prevent the ovum from reaching the sperm and uterus include:

  • Tubal cannulation during a hysterosalpingogram
  • Laparoscopy to remove adhesions or endometriosis
  • In vitro fertilisation (IVF)
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20
Q

What are the management options when uterine factors are the cause of infertility?

A

-Surgery may be used to correct polyps, adhesions or structural abnormalities affecting fertility.

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21
Q

What are the management options when Sperm Problems are the cause of infertility?

A
  • surgical sperm retrieval s used when there is a blockage somewhere along the vas deferens preventing sperm from reaching the ejaculated semen
  • Surgical correction of an obstruction in the vas deferens may restore male fertility
  • Intra-uterine insemination
  • Intracytoplasmic sperm injection (ICSI)
  • Donor insemination
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22
Q

what does semen analysis test for?

A

Semen analysis is used to examine
1. the quantity and
2. quality of semen and sperm.

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23
Q

Instructions for men to provide a semen sample:

A
  1. Abstain from ejaculation for at least 3 days and at most 7 days
  2. Avoid hot baths, sauna and tight underwear during the lead up to providing a sample
  3. Attempt to catch the full sample
  4. Deliver the sample to the lab within 1 hour of ejaculation
  5. Keep the sample warm (e.g. in underwear) before delivery
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24
Q

what lifestyle factors may affect quality and quantity of sperm:

A

Several lifestyle factors may affect the results of semen analysis and the quality and quantity of sperm:

  1. Hot baths
  2. Tight underwear
  3. Smoking
  4. Alcohol
  5. Raised BMI
  6. Caffeine
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25
Q

when is a repeat semen test indicated?

A

A repeat sample is indicated after 3 months in borderline results or earlier (2 – 4 weeks) with very abnormal results.

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26
Q

normal semen results:

A
  1. Semen volume (more than 1.5ml)
  2. Semen pH (greater than 7.2)
  3. Concentration of sperm (more than 15 million per ml)
  4. Total number of sperm (more than 39 million per sample)
  5. Motility of sperm (more than 40% of sperm are mobile)
  6. Vitality of sperm (more than 58% of sperm are active)
  7. Percentage of normal sperm (more than 4%)
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27
Q

what is polyspermia:

A

Polyspermia (or polyzoospermia) refers to a high number of sperm in the semen sample (more than 250 million per ml).

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28
Q

what is normospermia:

A

(or normozoospermia) refers to normal characteristics of the sperm in the semen sample.

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29
Q

what is oligospermia & further subdivisions:

A

Oligospermia (or oligozoospermia) is a reduced number of sperm in the semen sample. It is classified as:

  1. Mild oligospermia (10 to 15 million / ml)
  2. Moderate oligospermia (5 to 10 million / ml)
  3. Severe oligospermia (less than 5 million / ml)
  4. Cryptozoospermia refers to very few sperm in the semen sample (less than 1 million / ml).
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30
Q

what is azoospermia?

A

Azoospermia is the absence of sperm in the semen.

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31
Q

what are causes of male infertility spread as:

A
  1. Pre-testicular
  2. Testicular
  3. Post-testicular
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32
Q

what are pre-testicular causes of male infertility:

A

Testosterone is necessary for sperm creation. The hypothalamo-pituitary-gonadal axis controls testosterone. Hypogonadotrophic hypogonadism (low LH and FSH resulting in low testosterone), can be due to:

  1. Pathology of the pituitary gland or hypothalamus
  2. Suppression due to stress, chronic conditions or hyperprolactinaemia
  3. Kallman syndrome (ie anosmia & absent/delayed puberty): a type of hypogonadotropic hypogonadism (HH)
33
Q

testicular causes of male infertility:

A

Testicular damage from:

  1. Mumps
  2. Undescended testes
  3. Trauma
  4. Radiotherapy
  5. Chemotherapy
  6. Cancer

Genetic or congenital disorders that result in defective or absent sperm production, such as:

  1. Klinefelter syndrome
  2. Y chromosome deletions
  3. Sertoli cell-only syndrome
  4. Anorchia (absent testes)
34
Q

post-testicular causes of male infertility:

A

Obstruction preventing sperm being ejaculated can be caused by:

  1. Damage to the testicle or vas deferens from trauma, surgery or cancer
  2. Ejaculatory duct obstruction
  3. Retrograde ejaculation
  4. Scarring from epididymitis, for example, caused by chlamydia
  5. Absence of the vas deferens (may be associated with cystic fibrosis)
  6. Young’s syndrome (obstructive azoospermia, bronchiectasis and rhinosinusitis)
35
Q

Investigations for male infertility:

A

The initial steps for investigating abnormal semen analysis include a history, examination, repeat sample and ultrasound of the testes.

Patients with abnormal semen results are referred to a urologist for further investigations. Further investigations that may be considered include:

  1. Hormonal analysis with LH, FSH and testosterone levels
  2. Genetic testing
  3. Further imaging, such as transrectal ultrasound or MRI
  4. Vasography, which involves injecting contrast into the vas deferens and performing xray to assess for obstruction
  5. Testicular biopsy
36
Q

management of male infertility:

A

Management depends on the underlying cause, and can involve:

  1. Surgical sperm retrieval where there is obstruction
  2. Surgical correction of an obstruction in the vas deferens
  3. Intra-uterine insemination involves separating high-quality sperm, then injecting them into the uterus
  4. Intracytoplasmic sperm injection (ICSI) involves injecting sperm directly into the cytoplasm of an egg
  5. Donor insemination involves sperm from a donor
37
Q

when should infertility be investigated:

A

Investigation and referral for infertility should be initiated after the couple has been trying to conceive without success for 12 months. This can be reduced to 6 months if the woman is older than 35, as her ovarian stores are likely to be already reduced and time is more precious.

38
Q

causes of infertility:

A

Sperm problems (30%)
Ovulation problems (25%)
Tubal problems (15%)
Uterine problems (10%)
Unexplained (20%)
40% of infertile couples have a mix of male and female causes.

39
Q

statistics for conception/how many couples with fertility problems:

A

85% will conceive within a year of regular unprotected sex.
1 in 7 couples will struggle to conceive naturally.

40
Q

general advise for helping with conception:

A
  1. The woman should be taking 400mcg folic acid daily (or 5mg if : -Previous child with NTD
    -Diabetes mellitus
    -Woman on an anti-epileptic
    -Obesity
    -HIV positive taking co-trimoxazole -Sickle cell disease
  2. Aim for a healthy BMI
  3. Avoid smoking and drinking excessive alcohol
  4. Reduce stress as this may negatively affect libido and the relationship
  5. Aim for intercourse every 2 – 3 days
  6. Avoid timing intercourse

Timed intercourse to coincide with ovulation is not necessary or recommended as it can lead to increased stress and pressure in the relationship.

41
Q

Investigations for infertility in primary care:

A

Initial investigations, often performed in primary care:

  1. Body mass index (BMI) (low could indicate anovulation, high could indicate PCOS)
  2. Chlamydia screening
  3. Semen analysis
  4. Female hormonal testing (see below)
  5. Rubella immunity in the mother

Female hormone testing involves:

  1. Serum LH and FSH on day 2 to 5 of the cycle
  2. Serum progesterone on day 21 of the cycle (or 7 days before the end of the cycle if not a 28-day cycle).
  3. Anti-Mullerian hormone
  4. Thyroid function tests when symptoms are suggestive
  5. Prolactin (hyperprolactinaemia is a cause of anovulation) when symptoms of galactorrhea or amenorrhoea

High FSH suggests poor ovarian reserve (the number of follicles that the woman has left in her ovaries). The pituitary gland is producing extra FSH in an attempt to stimulate follicular development.

High LH (especially high LH: FSH ratio) may suggest polycystic ovarian syndrome (PCOS).

A rise in progesterone on day 21 indicates that ovulation has occurred, and the corpus luteum has formed and started secreting progesterone.

Anti-Mullerian hormone can be measured at any time during the cycle and is the most accurate marker of ovarian reserve. It is released by the granulosa cells in the follicles and falls as the eggs are depleted. A high level indicates a good ovarian reserve.

42
Q

further infertility investigations in secondary care

A
  1. Ultrasound pelvis to look for polycystic ovaries or any structural abnormalities in the uterus
  2. Hysterosalpingogram to look at the patency of the fallopian tubes
  3. Laparoscopy and dye test to look at the patency of the fallopian tubes, adhesions and endometriosis
43
Q

how is hysterosalpingogram performed?

A

A hysterosalpingogram is a type of scan used to assess the shape of the uterus and the patency of the fallopian tubes. Not only does it help with diagnosis, but it also has therapeutic benefit. It seems to increase the rate of conception without any other intervention.

-Tubal cannulation under xray guidance can be performed during the procedure to open up the tubes.

  1. A small tube is inserted into the cervix.
  2. A contrast medium is injected through the tube and fills the uterine cavity and fallopian tubes.
  3. Xray images are taken, and the contrast shows up on the xray giving an outline of the uterus and tubes.
  4. If the dye does not fill one of the tubes, this will be seen on an xray and suggests a tubal obstruction.

There is a risk of infection with the procedure, and often antibiotics are given prophylactically for patients with dilated tubes or a history of pelvic infection. Screening for chlamydia and gonorrhoea should be done before the procedure.

44
Q

how is laporoscopy and dye test performed:

A

The patient is admitted for laparoscopy.

During the procedure, dye is injected into the uterus and should be seen entering the fallopian tubes and spilling out at the ends of the tubes.
This will not be seen when there is tubal obstruction.

During laparoscopy, the surgeon can also assess for endometriosis or pelvic adhesions and treat these.

45
Q

Management of Anovulation:

A
  1. Weight loss for overweight patients with PCOS can restore ovulation
  2. Clomifene may be used to stimulate ovulation

Clomifene is an anti-oestrogen (a selective oestrogen receptor modulator). It is given on days 2 to 6 of the menstrual cycle. It stops the negative feedback of oestrogen on the hypothalamus, resulting in a greater release of GnRH and subsequently FSH and LH.

  1. Letrozole may be used instead of clomifene to stimulate ovulation (aromatase inhibitor with anti-oestrogen effects)
  2. Gonadotropins may be used to stimulate ovulation in women resistant to clomifene
  3. Ovarian drilling may be used in polycystic ovarian syndrome

Ovarian drilling involves laparoscopic surgery. The surgeon punctures multiple holes in the ovaries using diathermy or laser therapy. This can improve the woman’s hormonal profile and result in regular ovulation and fertility.

  1. Metformin may be used when there is insulin insensitivity and obesity (usually associated with PCOS)
46
Q

management of tubal factors:

A
  1. Tubal cannulation during a hysterosalpingogram
  2. Laparoscopy to remove adhesions or endometriosis
  3. In vitro fertilisation (IVF)
47
Q

management of uterine factors:

A

Surgery may be used to correct polyps, adhesions or structural abnormalities affecting fertility.

48
Q

each attempt of IVF have roughly what success rate?

A

25-30% at producing a live birth

49
Q

What does IVF involve?

A
  • fertilising an egg with sperm in a lab, then injecting the resulting embryo into the uterus.
  • very expensive and complicated process so couples are limited to a set number of cycles funded by the NHS
  • each attempt has a roughly 25 – 30% success rate at producing a live birth.
50
Q

What does a cycle of IVF involve?

A
  • A cycle of IVF involves a single episode of ovarian stimulation and collection of oocytes (eggs)
  • A single cycle may produce several embryos
  • Each of these embryos can be transferred separately in multiple attempts at pregnancy, all during one “cycle” of IVF
  • Embryos that are not used immediately may be frozen to be used at a later date.
  • Frozen embryos can potentially be used years later, even after a successful pregnancy.
51
Q

What are the steps of IVF?

A
  1. Suppressing the natural menstrual cycle
  2. Ovarian stimulation
  3. Oocyte collection
  4. Insemination / intracytoplasmic sperm injection (ICSI)
  5. Embryo culture
  6. Embryo transfer
52
Q

What are the 2 protocols for suppression of the natural menstrual cycle?

A
  • Suppression of the natural cycle involves either the use of GnRH agonists or GnRH antagonists
  • The choice between the GnRH agonist and GnRH antagonist protocol depends on individual factors
53
Q

Describe the GnRH agonist protocol for supression of the natural menstrual cycle

A
  • an injection of a GnRH agonist (e.g. goserelin) is given in the luteal phase of the menstrual cycle, around 7 days before the expected onset of the menstrual period
  • This initially stimulates the pituitary gland to secrete a large amount of FSH and LH.
  • However, after this initial surge in FSH and LH, there is negative feedback to the hypothalamus, and the natural production of GnRH is suppressed. This causes suppression of the menstrual cycle.
54
Q

Describe the GnRH antagonist protocol for supression of the natural menstrual cycle

A
  • daily subcutaneous injections of a GnRH antagonist (e.g. cetrorelix) are given, starting from day 5 – 6 of ovarian stimulation.
  • This suppresses the body releasing LH and causing ovulation to occur.
55
Q

Why is there a need to suppress the natural menstrual cycle?

A

Without suppression of the natural gonadotropins (LH and FSH) using one of the above protocols, ovulation would occur and the follicles that are developing would be released before it is possible to collect them.

56
Q

Describe the initial ovarian stimulation step of IVF

A
  • Ovarian stimulation involves using medications to promote the development of multiple follicles in the ovaries
  • starts at the beginning of the menstrual cycle (usually day 2), with subcutaneous injections of follicle-stimulating hormone (FSH) over 10 to 14 days
  • FSH stimulates the development of follicles, and this is closely monitored with regular transvaginal ultrasound scans
57
Q

When is the FSH stopped during the ovarian stimulation step of IVF?

A

When enough follicles have developed to an adequate size (usually around 18 millimetres),

58
Q

What is given after FSH is stopped during the ovarian stimulation step of IVF?

A
  • an injection of human chorionic gonadotropin (hCG) is given
  • this is given 36 hours before collection of the eggs
  • hCG works similarly to LH does naturally, and stimulates the final maturation of the follicles, ready for collection
  • This is referred to as a “trigger injection”.
59
Q

Describe the oocyte collection step of IVF

A
  • The oocytes (eggs) are collected from the ovaries under the guidance of a transvaginal ultrasound scan
  • A needle is inserted through the vaginal wall into each ovary to aspirate the fluid from each follicle
  • This fluid contains the mature oocytes from the follicles
  • fluid from the follicles is examined under the microscope for oocytes
  • procedure is usually performed under sedation
60
Q

Describe the oocyte insemination step of IVF

A
  • male produces a semen sample around the time of oocyte collection (Frozen sperm from earlier samples may be used)
  • sperm and egg are mixed in a culture medium
  • Thousands of sperm need to be combined with each oocyte to produce enough enzymes (e.g. hyaluronic acid) for one sperm to penetrate the corona radiata and zona pellucida and fertilise the egg.
61
Q

Describe the Intracytoplasmic Sperm Injection step of IVF

A
  • Intracytoplasmic sperm injection (ICSI) is a treatment used mainly for male factor infertility, where there are a reduced number or quality of sperm.
  • It is an addition to the IVF process.
  • After the eggs are harvested, and a semen sample is produced, the highest quality sperm are isolated and injected directly into the cytoplasm of the egg.
62
Q

Describe the embryo culture step of IVF

A
  • Dishes containing the fertilised eggs are left in an incubator and observed over 2 – 5 days to see which will develop and grow.
  • They are monitored until they reach the blastocyst stage of development (around day 5).
63
Q

Describe the embryo transfer step of IVF

A
  • After 2 – 5 days, the highest quality embryos are selected for transfer.
  • A catheter is inserted under ultrasound guidance through the cervix into the uterus
  • A single embryo is injected through the catheter into the uterus, and the catheter is removed
  • Generally, only a single embryo is transferred. Two embryos may be transferred in older women
  • Any remaining embryos can be frozen for future attempts at transfer
64
Q

what is intrauterine insemination?

A

Intrauterine insemination (IUI) is different from IVF. It is a more straightforward process, and involves injecting sperm into the uterus, avoiding intercourse.
IUI is used in cases such as donor sperm for same-sex couples, HIV (avoiding unprotected sex) and practical issues with vaginal sex.

65
Q

how is pregnancy checked after 1 round of IVF?

A

A pregnancy test is performed around day 16 after egg collection.

When this is positive, implantation has occurred. Even after a positive test, there is still the possibility of miscarriage or ectopic pregnancy.

66
Q

what happens if a pregnancy test is negative after 1 round of IVF?

A

When the pregnancy test is negative, implantation has failed. At this point, hormonal treatment is stopped. The woman will go on to have a menstrual period. The bleeding may be more substantial than usual given the additional hormones used during ovarian stimulation.

67
Q

what hormone is given from the time of oocyte collection and why?

A

Progesterone is used from the time of oocyte collection until 8 – 10 weeks gestation, usually in the form of vaginal suppositories. This is to mimic the progesterone that would be released by the corpus luteum during a typical pregnancy.

From 8 – 10 weeks the placenta takes over production of progesterone, and the suppositories are stopped.

68
Q

when is USS done after IVF?

A

An ultrasound scan is performed early in the pregnancy (around 7 weeks) to check for a fetal heartbeat, and rule out miscarriage or ectopic pregnancy. When the ultrasound scan confirms a health pregnancy, the remainder of the pregnancy can proceed with standard care, as with any other pregnancy:

You should be offered at least 2 scans:
1. an early pregnancy scan (dating or booking scan) between 11 and 14 weeks
2. a mid-pregnancy scan (also known as a fetal anomaly scan) between 18 and 21 weeks

69
Q

what are the main complications of IVF:

A
  1. Failure
  2. Multiple pregnancy
  3. Ectopic pregnancy
  4. Ovarian hyperstimulation syndrome
70
Q

what are complications of the egg collection process:

A
  1. Pain
  2. Bleeding
  3. Pelvic infection
  4. Damage to the bladder or bowel
71
Q

what is ovarian hyperstimulation syndrome?

A

Ovarian hyperstimulation syndrome (OHSS) is a complication of ovarian stimulation during IVF infertility treatment. It is associated with the use of human chorionic gonadotropin (hCG) to mature the follicles during the final steps of ovarian stimulation.

72
Q

what is the pathophysiology of ovarian hyperstimulation syndrome?

A

The primary mechanism for OHSS is an increase in vascular endothelial growth factor (VEGF) released by the granulosa cells of the follicles. VEGF increases vascular permeability, causing fluid to leak from capillaries. Fluid moves from the intravascular space to the extravascular space. This results in oedema, ascites and hypovolaemia.

The use of gonadotrophins (LH and FSH) during ovarian stimulation results in the development of multiple follicles. OHSS is provoked by the “trigger injection” of hCG 36 hours before oocyte collection. HCG stimulates the release of VEGF from the follicles. The features of the condition begin to develop after the hCG injection.

There is also activation of the renin-angiotensin system. A notable finding in patients with OHSS is a raised renin level. The renin level correlates with the severity of the condition.

73
Q

what are risk factors for ovarian hyperstimulation syndrome?

A
  1. Younger age
  2. Lower BMI
  3. Raised anti-Müllerian hormone
  4. Higher antral follicle count
  5. Polycystic ovarian syndrome
  6. Raised oestrogen levels during ovarian stimulation
74
Q

how is ovarian hyperstimulation syndrome prevented?

A

Women are individually assessed for their risk of developing OHSS.

During stimulation with gonadotrophins, they are monitored with:

  1. Serum oestrogen levels (higher levels indicate a higher risk)
  2. Ultrasound monitor of the follicles (higher number and larger size indicate a higher risk)

In women at higher risk several strategies may be used to reduce the risk:

  1. Use of the GnRH antagonist protocol (rather than the GnRH agonist protocol)
  2. Lower doses of gonadotrophins
  3. Lower dose of the hCG injection
  4. Alternatives to the hCG injection (i.e. a GnRH agonist or LH)
75
Q

what are features of ovarian hyperstimulation syndrome:

A

Early OHSS presents within 7 days of the hCG injection. Late OHSS presents from 10 days onwards.

Features of the condition include:

  1. Abdominal pain and bloating
  2. Nausea and vomiting
  3. Diarrhoea
  4. Hypotension
  5. Hypovolaemia
  6. Ascites
  7. Pleural effusions
  8. Renal failure
  9. Peritonitis from rupturing follicles releasing blood
  10. Prothrombotic state (risk of DVT and PE)
76
Q

How is severity of OHHS assessed (& when to admit)?

A

Mild: Abdominal pain and bloating

Moderate: Nausea and vomiting with ascites seen on ultrasound

Severe: Ascites, low urine output (oliguria), low serum albumin, high potassium and raised haematocrit (>45%)

Critical: Tense ascites, no urine output (anuria), thromboembolism and acute respiratory distress syndrome (ARDS)

-Patients with mild to moderate OHSS are often managed as an outpatient.

-Severe cases require admission

-critical cases may require admission to the intensive care unit (ICU).

77
Q

what is the management of OHSS:

A

Management is supportive with treatment of any complications. This involves:

  1. Oral fluids
  2. Monitoring of urine output
  3. Low molecular weight heparin (to prevent thromboembolism)
  4. Ascitic fluid removal (paracentesis) if required
  5. IV colloids (e.g. human albumin solution)
78
Q

what may used to assess volume of fluid in intravascular space:

A

Haematocrit may be monitored to assess the volume of fluid in the intravascular space.

Haematocrit is the concentration of red blood cells in the blood. When the haematocrit goes up, this indicates less fluid in the intravascular space, as the blood is becoming more concentrated.

Raised haematocrit can indicate dehydration.