5.2: Infertility and Contraception Flashcards
Define coitus interruptus
the pull out method
Name three methods of ‘natural contraception’
- Abstinence
- Coitus interruptus
- Rhythm method (getting to know your cycle really well)
Define vasectomy, other than it being reversible in some cases, what is one disadvantage to this form of contraception?
Cutting (distal to the superficial inguinal ring) the vas deferens to ensure the ejaculate is free of sperm.
One disadvantage is it’s not immediately effective since there may still be sperm existing in the male tract
Name three barrier methods of contraception, what product can they all be used in conjunction with?
- Condoms
- Diaphragm: lies diagonally across cervix, doesn’t completely occlude passage of sperm but holds the sperm in an acidic environment of the vagina to reduce its survival time
- Cap: first across the cervix (physical barrier)
Can be used with spermicide: Product inserted into vagina prior to intercourse that kills sperm
What is a combined OCP and how does it work?
Hormonal contraception: Has estrogen and progesterone which:
1. stimulates -ve feedback to the hypothalamus/pituitary to inhibit follicular development/ovulation
- Loss of the estrogen positive feedback means no LH surge
Name three methods of taking hormonal contraception
The pill, patch and injections
What forms of contraception inhibit the transport of the oocyte down the fallopian tube? Is it 100% effective?
Sterilization to occlude the fallopian tubes; clips, rings, ligation
*Tubes rarely rejoin
What form of contraception inhibits sperm from passing through the cervix chemically? (Not physically)
Can change the cervical mucus to make it thick and ‘hostile’ using the combined OCP, or progesterone only pill, implant or depot progesterone/injections
*excess progesterone tricks the body into thinking its pregnant; inducing changes in the endometrium, cervical mucus, etc
Name two potential consequences of having excessive progesterone in the body?
- Can induce over-proliferation of endometrium - leading to cancer
- Excessive suppression of estrogen
Name three forms of contraception that can inhibit implantation of the embryo in the uterine lining
- Hormonal contraception: can affect the receptivity of the endometrium
- Postcoital contraception
- IUDs
What are the two main types of IUDs and how do they work?
Can be hormonal or copper:
1. Copper interferes with the endometrial enzymes to prevent implantation and acts a physical barrier against sperm transport
- Progesterone; -ve feedback in the axis
Is male hormonal contraception currently available, why or why not? Which hormone would be involved?
No, some trials have been successful with testosterone being the most suitable exogenous hormone (used in combination with progesterone to reduce the side effects). However, issues such as low level sperm production, persisting side effects (i.e mood swings), reversibility and problems caused with the male repro tract/sexual function still need to be overcome
Define infertility (and primary and secondary)
Being unable to conceive within 1 year
Primary: no previous pregnancy
Secondary: previous pregnancy, successful or not
Name four factors that might contribute to male infertility (not psychological)
- Low sperm count
- Poor sperm morphology/motility
- Low ejaculate volume; not adequate release from accessory glands
- Sperm autoimmunity
Name two factors that contribute to male infertility during coitus (intercourse ;)
- Retrograde ejaculation: semen enters bladder rather than emerging through the penis
- ED
Name three major factors that can cause female infertility. Briefly describe each and include the proportion of women with each type of problem
- Ovulatory failure: Hormone imbalance or polycystic ovaries, 13%
- Impaired gamete/zygote transport; tube defects, anti-sperm antibodies, non-optimal cervical mucous, 12%
- Implantation defects; mostly due to problems with embryo itself that make it unable to reach the blastocyst stage; i.e; chromosomal abnormalities or endometrial abnormalities (endometriosis is 6%)
Define anovulation, is it ever normal?
When ovaries do not release an oocyte during a menstrual cycle, occasionally normal at the extreme ends of reproductive life
What are 6 potential causes of anovulation?
- Stress factors; stress, exercise, weight loss
- Pituitary tumours
- Necrosis
- Ovarian failure
- Menopause
- Chemicals: radio/chemotherapy
Why can polycystic ovarian syndrome result in female infertility? What other diseases can arise as result of PCOS?
The syndrome is related to a lack of pulsatile GnRH secretions and increased androgen secretions; which raises/confuses the LH/FSH ratio - making proper follicular development difficult. The follicles respond to pituitary hormones by producing an abnormal pattern of estrogen secretions - and chronic anovulation is thought to occur due to inappropriate feedback signals from the ovary to the hypothalamus/pituitary.
The abnormal estrogen secretions put women at risk of endometrial malignancy. PCOS can also cause insulin resistance, potentially leading to type 2 diabetes.
How might you diagnose anovulation?
Can measure hormone levels in the blood
Name three methods you can use to induce ovulation in a patient with anovulation
Can induce ovulation with
1. anti-estrogen: tricks the body into thinking estrogen levels are low so there’s an increase in FSH
- Gonadotrophins: like FSH
- GnRH agonists; pulsatile to mimic a normal secretion
What is tubal occlusion and what particular feature in a patient history might lead you to suspect one? Name two causes, two methods for diagnosis and two treatment options
Occlusion of the fallopian tubes so eggs cannot be transported, particularly suspected if there was a previous pelvic infection
Causes: scarring (from infection or endometriosis), sterilization
Diagnosed by: laparoscopy and dye, hysterosalpingogram/HSG (X-ray involving a thin tube threaded through and a contrast material injected into the uterus)
Treatment: tubal surgery (reanastomosis) or assisted conception (insert fertilized embryo from the lab into the uterine lining)
Name three factors that might be causing abnormal sperm production
- Testicular disease
- Obstruction of the ducts due to an infection or vasectomy
- Hypothalamic/pituitary dysfunction
List the values that correspond with each category in a normal semen analysis:
a) Volume
b) sperm count
c) % of sperm in the semen that are motile
d) % of sperm in the semen with a normal morphology
What is the normal range of sperm count (millions/ml)
a) 1.5-4mL
b) >15 million/mL
c) >40%
d) >4%
The normal range is 20-200 million sperm/ml
Name four things you may have to check when managing a couple with suspected infertility
- Ensure they are having regular unprotected sex
- Regular menstrual cycle (it’s 21-35 days) and day 21 progesterone levels are normal (serum levels should peak at 21 days, this provides evidence that ovulation has occurred)
- Check the patient tubes; history of infection, sterilization and can investigate with dye insufflation or HSG
- Adequate sperm count
Name three major methods you can use to manage/solve infertility.
When can’t you manage infertility?
- Drugs to overcome hormone problems
- Surgery to overcome tubal occlusion
- Overcome timing/fertilization issues with IVF
* No treatment if there is an issue with implantation as an embryo cannot be grown to full fetal development in a lab
How does an IVF work?
- Stimulates the ovary to release more oocytes (so you have more to play with and potentially freeze),
- Take a sperm sample and fertilize the oocyte in vitro (lab).
- Allow the embryo to develop up to the blastocyst stage in vitro before transferring it back to the uterus
Name four ways you could overcome the issue of inadequate sperm/sperm transport in a couple when providing IVF?
IUI: intrauterine insemination
ICSI: intracytoplasmic sperm injection
TESA: testicular sperm aspiration
GIFT: gamete inrafallopian transfer
Name two ways you could overcome the issue of inadequate eggs when providing a couple with IVF
Bonus: include a scenario/condition that often requires one of these solutions
- Egg donation
2. CT (cytoplasmic transfer); often relating to the mitochondria, like mitochondrial disease
What is often the cause of early miscarriages/ spontaneous abortions in women who become pregnant shortly after discontinuing the pill? What can be concluded from this?
Chromosomal abnormalities resulting from nondisjunction; such as polyploidy (cells containing 3 or more times the number of haploid chromosomes)
In conclusion, it is wise to use another type of contraception 1-2 menstrual cycles before attempting to get pregnant
What proportion of young couples that have regular unprotected sex are expected to conceive within a year?
85%
How does hyperprolactinemia cause infertility and what clinical sign may indicate this diagnosis?
May stop a woman from ovulating, may be diagnosed by observing the production of small quantities of milk
How does a patient with PCOS tend to present clinically?
Secondary amenorrhea/infertility, hirsutism (abnormal growth of facial and bodily hair especially on a woman) and obesity
What does the abnormal estrogen secretions put women with PCOS at risk of?
Endometrial malignancy!
Briefly describe the mechanism of action of the ‘morning-after pill’
Estrogen taken in large doses within 72 hours of intercourse usually prevent implantation (not fertilization) of the blastocyst; likely by altering tubal motility, interfering with corpus luteum function, causing abnormal changes in the endometrium
