Subfertility

Sexual and Reproductive Health

Clinicals - History

Fact Explanation
Age of both partners Fertility rate in both males and females have shown to reduce with advanced age. Evaluation for subfertility should start early when the partners are older particularly if the woman is older than 35 years. Age of both partners
Fertility rate in both males and females have shown to reduce with advanced age. Evaluation for subfertility should start early when the partners are older particularly if the woman is older than 35 years.
Duration of subfertility This is important to diagnose presence of subfertility as the definition states, not being able to conceive after 1 year of unprotected vaginal sexual intercourse, in the absence of any known reproductive pathology. Duration of subfertility
This is important to diagnose presence of subfertility as the definition states, not being able to conceive after 1 year of unprotected vaginal sexual intercourse, in the absence of any known reproductive pathology.
Methods used for contraception It is important to determine if the couple is on a long term contraceptive method such as subdermal implants or Intrauterine device so that it will have to be discontinued as there is expectations of pregnancy and that they are engaging in unprotected vaginal intercourse. Methods used for contraception
It is important to determine if the couple is on a long term contraceptive method such as subdermal implants or Intrauterine device so that it will have to be discontinued as there is expectations of pregnancy and that they are engaging in unprotected vaginal intercourse.
Frequency of sexual intercourse In order to achieve conception the couple should engage in regular sexual intercourse so this factor has to be elicited during the history taking. 90% of fertile couples become pregnant within a year of regular intercourse. After two years, this rises to 95%. Frequency of sexual intercourse
In order to achieve conception the couple should engage in regular sexual intercourse so this factor has to be elicited during the history taking. 90% of fertile couples become pregnant within a year of regular intercourse. After two years, this rises to 95%.
Menstrual history of the woman Presence of oligomenorrhoea, amenorrhoea may indicate a problem with hypothalamo pituitary ovarian axis. Women who are not ovulating may have variable cycle lengths, oligomenorrhoea, or amenorrhoea. Oligomenorrhoea or amenorrhoea can present as part of polycystic ovary syndrome. Menstrual history of the woman
Presence of oligomenorrhoea, amenorrhoea may indicate a problem with hypothalamo pituitary ovarian axis. Women who are not ovulating may have variable cycle lengths, oligomenorrhoea, or amenorrhoea. Oligomenorrhoea or amenorrhoea can present as part of polycystic ovary syndrome.
History of endometriosis/ adenomyosis Both these conditions are associated with female subfertility when they cause structural damage or adhesions. History of endometriosis/ adenomyosis
Both these conditions are associated with female subfertility when they cause structural damage or adhesions.
History of pelvic infections or sexually transmitted infections Subfertility is a long term complication of pelvic inflammatory disease (PID). Chlamydia and gonorrhoea are the major pathogens that cause pelvic inflammatory disease. If untreated, pelvic inflammatory disease can cause tubal factor subfertility. Bacterial vaginosis increases risk of PID and infertility in women. Trichomanas vaginalis can cause female tubal infertility and male infertility. Human papilloma virus infection can reduce sperm motility and induce abortion. Human immunodeficiency virus infection can reduce sperm quality History of pelvic infections or sexually transmitted infections
Subfertility is a long term complication of pelvic inflammatory disease (PID). Chlamydia and gonorrhoea are the major pathogens that cause pelvic inflammatory disease. If untreated, pelvic inflammatory disease can cause tubal factor subfertility. Bacterial vaginosis increases risk of PID and infertility in women. Trichomanas vaginalis can cause female tubal infertility and male infertility. Human papilloma virus infection can reduce sperm motility and induce abortion. Human immunodeficiency virus infection can reduce sperm quality
Symptoms such as constipation, cold intolerance, heavy menstrual blood loss, lethargy,weight gain with reduced appetite etc May indicate presence of hypothyroidism which affects fertility. Symptoms such as constipation, cold intolerance, heavy menstrual blood loss, lethargy,weight gain with reduced appetite etc
May indicate presence of hypothyroidism which affects fertility.
Symptoms such as diarrhea, heat intolerance, scanty or absent menstruation, weight loss with increased appetite etc May indicate presence of hyperthyroidism that can also affect fertility. Symptoms such as diarrhea, heat intolerance, scanty or absent menstruation, weight loss with increased appetite etc
May indicate presence of hyperthyroidism that can also affect fertility.
History of previous pregnancies and their out come This is important in prognostication because a previous full term pregnancy is associated with a better chance of conception, either naturally or after treatment. History of previous pregnancies and their out come
This is important in prognostication because a previous full term pregnancy is associated with a better chance of conception, either naturally or after treatment.
History of erectile dysfunction or premature ejaculation in male and vaginismus or dysperunia in female These can affect the coital frequency in the couple and thus affect fertility. History of erectile dysfunction or premature ejaculation in male and vaginismus or dysperunia in female
These can affect the coital frequency in the couple and thus affect fertility.
History of occupational heat or radiation exposure in males These can affect semen quality or cause oligospermia in males. History of occupational heat or radiation exposure in males
These can affect semen quality or cause oligospermia in males.
History of mumps or measles in males These infections can cause orchitis and affect sperm production. History of mumps or measles in males
These infections can cause orchitis and affect sperm production.
History of testicular trauma, torsion of testes, undescended testes These may cause oligospermia or testicular failure. History of testicular trauma, torsion of testes, undescended testes
These may cause oligospermia or testicular failure.
History of pelvic/ testicular/inguinal/scrotal/retroperitoneal surgery or irradiation or chemotherapy In females pelvic surgery can cause adhesions and tubal factor subfertility. In males this kind of surgery can cause ejaculatory dysfunction, vas deference obstruction etc. Irradiation and chemotherapy can cause gonadal failure History of pelvic/ testicular/inguinal/scrotal/retroperitoneal surgery or irradiation or chemotherapy
In females pelvic surgery can cause adhesions and tubal factor subfertility. In males this kind of surgery can cause ejaculatory dysfunction, vas deference obstruction etc. Irradiation and chemotherapy can cause gonadal failure
Histroy of current or recent acute or chronic medical illnesses Recurrent respiratory infections may be the presentation of cilliary dysfunction syndromes such as Kartagener's syndrome that cause male infertility. Chronic infections, other endocrine disorders etc. can also reduce fertility. Histroy of current or recent acute or chronic medical illnesses
Recurrent respiratory infections may be the presentation of cilliary dysfunction syndromes such as Kartagener's syndrome that cause male infertility. Chronic infections, other endocrine disorders etc. can also reduce fertility.
History regarding medication Anabolic steroids use can lead to hypogonadism. Medicines such as sulfasalazine, methotrexate, colchicine, cimetidine, spironolactone can affect fertility. History regarding medication
Anabolic steroids use can lead to hypogonadism. Medicines such as sulfasalazine, methotrexate, colchicine, cimetidine, spironolactone can affect fertility.
Social history regarding smoking and alcohol consumption Smoking and alcohol consumption has shown to affect fertility. Smoking reduce fertility in women and reduce semen quality in men.Excess alcohol consumption during pregnancy is toxic to the fetus and excessive alcohol intake also reduce semen quality. Social history regarding smoking and alcohol consumption
Smoking and alcohol consumption has shown to affect fertility. Smoking reduce fertility in women and reduce semen quality in men.Excess alcohol consumption during pregnancy is toxic to the fetus and excessive alcohol intake also reduce semen quality.
Headache, blurred vision, visual field defects These can be the presenting symptoms of a pituitary adenoma. Headache, blurred vision, visual field defects
These can be the presenting symptoms of a pituitary adenoma.

Clinicals - Examination

Fact Explanation
Body mass index BMI over 30 and below 19 have shown to be associated with subfertility. Body mass index
BMI over 30 and below 19 have shown to be associated with subfertility.
Hirsutism in females Is a feature of poly cystic ovarian syndrome Hirsutism in females
Is a feature of poly cystic ovarian syndrome
Secondary sexual characteristics Should be examined in order to diagnose genetic and endocrine problems that may cause subfertility Secondary sexual characteristics
Should be examined in order to diagnose genetic and endocrine problems that may cause subfertility
Testicular position and volume Genital examination is important to determine presence of undescended testes, underdeveloped testis, testicular tumor impalpable vas deferens, varicocele, inguinal scars from unreported inguinal surgery etc that can lead to infertility in males Testicular position and volume
Genital examination is important to determine presence of undescended testes, underdeveloped testis, testicular tumor impalpable vas deferens, varicocele, inguinal scars from unreported inguinal surgery etc that can lead to infertility in males
Presence of vaginal/penile discharge This may indicate presence of sexually transmitted infection Presence of vaginal/penile discharge
This may indicate presence of sexually transmitted infection
Size and characteristics of uterus and ovaries palpated abdominally and bimanually Determined to exclude presence of uterine and ovarian masses, normal uterine anatomy, endometritic nodules etc that can contribute to female subfertility Size and characteristics of uterus and ovaries palpated abdominally and bimanually
Determined to exclude presence of uterine and ovarian masses, normal uterine anatomy, endometritic nodules etc that can contribute to female subfertility
Body habitus Alterations in the normal body habitus may indicate presence of endocrine disorders.
Gynecomastia, galactorrhea may be observed in patients with pituitary adenomas.
Tall males with other features such as gynecomastia, less muscular body, less facial and body hair etc may indicate Klinefelter syndrome
Body habitus
Alterations in the normal body habitus may indicate presence of endocrine disorders.
Gynecomastia, galactorrhea may be observed in patients with pituitary adenomas.
Tall males with other features such as gynecomastia, less muscular body, less facial and body hair etc may indicate Klinefelter syndrome

Investigations - Diagnosis

Fact Explanation
Seminal fluid analysis According to World Health Organization reference values semen volume should be 1.5 ml or more; pH 7.2 or more; sperm concentration 15 million spermatozoa per ml or more; total sperm number 39 million spermatozoa per ejaculate or more; total motility 40% or more motile, or progressive motility 32% or more; vitality 58% or more live spermatozoa and sperm morphology 4% or more normal forms.
At least two semen samples should be tested at least two or three weeks apart before a diagnosis is made.
Seminal fluid analysis
According to World Health Organization reference values semen volume should be 1.5 ml or more; pH 7.2 or more; sperm concentration 15 million spermatozoa per ml or more; total sperm number 39 million spermatozoa per ejaculate or more; total motility 40% or more motile, or progressive motility 32% or more; vitality 58% or more live spermatozoa and sperm morphology 4% or more normal forms.
At least two semen samples should be tested at least two or three weeks apart before a diagnosis is made.
Serum Follicular stimulating hormone level(FSH) Both high and low FSH levels may be associated with hypogonadism. High levels suggest gonadal failure. Low level may suggest presence of hypogonadotropic hypogonadism Serum Follicular stimulating hormone level(FSH)
Both high and low FSH levels may be associated with hypogonadism. High levels suggest gonadal failure. Low level may suggest presence of hypogonadotropic hypogonadism
Serum luteinizing hormone level(LH) If serum LH level is raised, with a normal FSH level suggests PCOS. High LH level together with high FSH may suggest premature menopause (ovarian failure).
Low levels of LH are common in women with eating disorders, female athletes, high levels of stress and disorders of the pituitary or hypothalamus. LH surge is required for ovulation. Therefore low LH levels result in anovulation and subfertility
Serum luteinizing hormone level(LH)
If serum LH level is raised, with a normal FSH level suggests PCOS. High LH level together with high FSH may suggest premature menopause (ovarian failure).
Low levels of LH are common in women with eating disorders, female athletes, high levels of stress and disorders of the pituitary or hypothalamus. LH surge is required for ovulation. Therefore low LH levels result in anovulation and subfertility
Serum testosterone level Low testosterone levels in men suggests presence of hypogonadism. If associated with Low FSH level can diagnose hypogonadotropic hypogonadism Serum testosterone level
Low testosterone levels in men suggests presence of hypogonadism. If associated with Low FSH level can diagnose hypogonadotropic hypogonadism
Serum prolactin level High prolactin levels inhibit secretion of FSH. Therefore, if your prolactin levels are high, ovulation is suppressed leading to infertility. High prolactin level warrants further investigations to rule out pituitary tumour. Serum prolactin level
High prolactin levels inhibit secretion of FSH. Therefore, if your prolactin levels are high, ovulation is suppressed leading to infertility. High prolactin level warrants further investigations to rule out pituitary tumour.
Serum Thyroid stimulating hormone level Done to rule out hypothyroidism or hyperthyroidism in symptomatic patients. Serum Thyroid stimulating hormone level
Done to rule out hypothyroidism or hyperthyroidism in symptomatic patients.
Serum anti mullerian hormone level Is a good indicator of ovarian follicular reserve. Serum anti mullerian hormone level
Is a good indicator of ovarian follicular reserve.
Mid luteal progesterone assay Done to assess ovulation. A rise in the mid luteal level of progesterone suggest that ovulation has taken place. Mid luteal progesterone assay
Done to assess ovulation. A rise in the mid luteal level of progesterone suggest that ovulation has taken place.
Transvaginal ultrasound scan Is a basic imaging test done in women to assess Fallopian tubes, uterus, and pelvis. Transvaginal ultrasound scan
Is a basic imaging test done in women to assess Fallopian tubes, uterus, and pelvis.
Hysterosalpingogram Done to assess tubal patency in women to rule out tubal factor subfertility. Hysterosalpingogram
Done to assess tubal patency in women to rule out tubal factor subfertility.
Laparoscopy Is considered the gold standard to evaluate pelvic pathology in women. Laparoscopy
Is considered the gold standard to evaluate pelvic pathology in women.
Scrotal ultrasound scan Done to detect varicocele, hydrocele, cysts. abacess, tumours etc Scrotal ultrasound scan
Done to detect varicocele, hydrocele, cysts. abacess, tumours etc
Testicular biopsy Done to find cause for male infertility when a semen analysis suggests presence of abnormal sperms but hormone assays are normal. In some cases, sperm obtained from a testicular biopsy can be used for in vitro fertilization. Testicular biopsy
Done to find cause for male infertility when a semen analysis suggests presence of abnormal sperms but hormone assays are normal. In some cases, sperm obtained from a testicular biopsy can be used for in vitro fertilization.
Hysteroscopy Is done to visualize inside the uterus to rule out conditions such as congenital uterine anomalies, fibroids,polyps, uterine synechiae etc. Hysteroscopy
Is done to visualize inside the uterus to rule out conditions such as congenital uterine anomalies, fibroids,polyps, uterine synechiae etc.
Transrectal ultrasonography Can be performed to rule out ejaculatory duct obstruction Transrectal ultrasonography
Can be performed to rule out ejaculatory duct obstruction
Postejaculatory urinalysis Done in patients with a low volume of ejaculate, to rule out retrograde ejaculation Postejaculatory urinalysis
Done in patients with a low volume of ejaculate, to rule out retrograde ejaculation
Screen for sexually transmitted infections(STI) Should be done if STI are suspected Screen for sexually transmitted infections(STI)
Should be done if STI are suspected

Investigations - Management

Fact Explanation
Full blood count Done to exclude anemia in preparing for pregnancy. Full blood count
Done to exclude anemia in preparing for pregnancy.

Management - Supportive

Fact Explanation
Weight control Has shown to improve fertility in both females and males. For women who have a BMI of 30 or above, losing weight is likely to increase their chance of conception and women who have a BMI of less than 19, increasing body weight is likely
to improve their chance of conception. Men who have a BMI of 30 or above are likely to
have reduced fertility.
Weight control
Has shown to improve fertility in both females and males. For women who have a BMI of 30 or above, losing weight is likely to increase their chance of conception and women who have a BMI of less than 19, increasing body weight is likely
to improve their chance of conception. Men who have a BMI of 30 or above are likely to
have reduced fertility.
Smoking cessation Studies have shown that smoking reduce fertility in women and reduce semen quality in men. Smoking cessation
Studies have shown that smoking reduce fertility in women and reduce semen quality in men.
Limit alcohol consumption Excess alcohol consumption during pregnancy is toxic to the fetus so women should limit alcohol to 1 or 2 units once or twice per week and avoid episodes of intoxication. Excessive alcohol intake has shown to reduce semen quality. Limit alcohol consumption
Excess alcohol consumption during pregnancy is toxic to the fetus so women should limit alcohol to 1 or 2 units once or twice per week and avoid episodes of intoxication. Excessive alcohol intake has shown to reduce semen quality.
Preconceptional folate and councelling Women who are planning to conceive should take folic acid in order to prevent neural tube defects in the fetus. 0.4 mg daily is the required dose. But if there was a history of neural tube defect in a previous pregnancy the recommended dose is 5 mg. Preconceptional folate and councelling
Women who are planning to conceive should take folic acid in order to prevent neural tube defects in the fetus. 0.4 mg daily is the required dose. But if there was a history of neural tube defect in a previous pregnancy the recommended dose is 5 mg.
Avoid heat exposure at work, wearing tight under wear etc in males These measures are important because elevated scrotal temperature is shown to be associated with reduced semen quality, Avoid heat exposure at work, wearing tight under wear etc in males
These measures are important because elevated scrotal temperature is shown to be associated with reduced semen quality,
Advice on regular sexual intercourse Unprotected vaginal sexual intercourse at least 2-3 times in a week is required for a successful conception. The natural conception rate for couples who have regular unprotected sexual intercourse is shown to be over 90% in three years time. Advice on regular sexual intercourse
Unprotected vaginal sexual intercourse at least 2-3 times in a week is required for a successful conception. The natural conception rate for couples who have regular unprotected sexual intercourse is shown to be over 90% in three years time.

Management - Specific

Fact Explanation
Ovulation induction Most commonly used agent is clomifene citrate. It is an anti-estrogen agent that occupies hypothalamic estrogen receptors and interrupy normal feed back mechanisms, increasing release of FSH. FSH stimulate ovaries to produce more follicles.
Ovulation induction can also be done by laparoscopic ovarian drilling in cases of polycystic ovarian syndrome unresponsive to medical treatment.
Ovulation induction
Most commonly used agent is clomifene citrate. It is an anti-estrogen agent that occupies hypothalamic estrogen receptors and interrupy normal feed back mechanisms, increasing release of FSH. FSH stimulate ovaries to produce more follicles.
Ovulation induction can also be done by laparoscopic ovarian drilling in cases of polycystic ovarian syndrome unresponsive to medical treatment.
Intrauterine insemination A prepared small sample of sperm is introduced into the uterine cavity with a fine uterine catheter. Suitable for people with unexplained infertility, mild endometriosis or mild male factor infertility. Intrauterine insemination
A prepared small sample of sperm is introduced into the uterine cavity with a fine uterine catheter. Suitable for people with unexplained infertility, mild endometriosis or mild male factor infertility.
In vitro fertilization(IVF) IVF treatment is offered to women with unexplained infertility who have not conceived after 2 years of regular unprotected sexual intercourse. Ovarian stimulation is done and eggs are collected under ultrasound guidance. These eggs are fertilized in a petri dish with sperm or intracytoplasmic sperm injection. The fertilized embryos are then transferred into uterine cavity. A pregnancy test is performed after 2 weeks to to confirm conception. In vitro fertilization(IVF)
IVF treatment is offered to women with unexplained infertility who have not conceived after 2 years of regular unprotected sexual intercourse. Ovarian stimulation is done and eggs are collected under ultrasound guidance. These eggs are fertilized in a petri dish with sperm or intracytoplasmic sperm injection. The fertilized embryos are then transferred into uterine cavity. A pregnancy test is performed after 2 weeks to to confirm conception.
Surgical treatment Surgical procedures such as laparoscopy for ablation of endometriosis, myomectomy for uterine fibroids, tubal surgery to relieve blocked Fallopian tubes etc are done to restore fertility. Surgical treatment
Surgical procedures such as laparoscopy for ablation of endometriosis, myomectomy for uterine fibroids, tubal surgery to relieve blocked Fallopian tubes etc are done to restore fertility.

Concise, fact-based medical articles to refresh your knowledge

Access a wealth of content and skim through a smartly presented catalog of diseases and conditions.

  1. AKSGLAEDE L, JUUL A. Testicular function and fertility in men with Klinefelter syndrome: a review. Eur J Endocrinol [online] 2013 Apr, 168(4):R67-76 [viewed 20 August 2014] Available from: doi:10.1530/EJE-12-0934
  2. ALAINA B. JOSE-MILLER, JENNIFER W. BOYDEN, KEITH A. FREY. Infertility. Am Fam Physician.[online] 2007 Mar 15;75(6):849-856.[viewed on 20 Aug 2014] Available from; http://www.aafp.org/afp/2007/0315/p849.html
  3. ALAINA B. JOSE-MILLER, JENNIFER W. BOYDEN, KEITH A. FREY. Infertility. Am Fam Physician.[online] 2007 Mar 15;75(6):849-856.[viewed on 20 Aug 2014] Available from; http://www.aafp.org/afp/2007/0315/p849.html
  4. ANGEL M, GHOSE S, GOWDA M. A randomized trial comparing the ovulation induction efficacy of clomiphene citrate and letrozole. J Nat Sci Biol Med [online] 2014 Jul, 5(2):450-2 [viewed 20 August 2014] Available from: doi:10.4103/0976-9668.136241
  5. ANIFANDIS G, MESSINI C, DAFOPOULOS K, SOTIRIOU S, MESSINIS I. Molecular and Cellular Mechanisms of Sperm-Oocyte Interactions Opinions Relative to in Vitro Fertilization (IVF). Int J Mol Sci [online] 2014 Jul 22, 15(7):12972-97 [viewed 20 August 2014] Available from: doi:10.3390/ijms150712972
  6. APARI P, DE SOUSA JD, MüLLER V. Why Sexually Transmitted Infections Tend to Cause Infertility: An Evolutionary Hypothesis PLoS Pathog [online] , 10(8):e1004111 [viewed 22 August 2014] Available from: doi:10.1371/journal.ppat.1004111
  7. AQUINO CI, NORI SL. Complementary therapy in polycystic ovary syndrome. Transl Med UniSa [online] 2014 Apr:56-65 [viewed 20 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/24809037
  8. ARYANPUR M, TARAHOMI M, SHARIFI H, HEYDARI G, HESSAMI Z, AKHOUNDI M, MASJEDI MR. Comparison of spermatozoa quality in male smokers and nonsmokers of Iranian infertile couples. Int J Fertil Steril [online] 2011 Oct, 5(3):152-7 [viewed 19 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/25101159
  9. CAHILL DJ, WARDLE PG. Management of infertility BMJ [online] 2002 Jul 6, 325(7354):28-32 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1123548
  10. CHANG EM, SONG HS, LEE DR, LEE WS, YOON TK. In vitro maturation of human oocytes: Its role in infertility treatment and new possibilities. Clin Exp Reprod Med [online] 2014 Jun, 41(2):41-6 [viewed 20 August 2014] Available from: doi:10.5653/cerm.2014.41.2.41
  11. DE FLEURIAN G, PERRIN J, ECOCHARD R, DANTONY E, LANTEAUME A, ACHARD V, GRILLO JM, GUICHAOUA MR, BOTTA A, SARI-MINODIER I. Occupational exposures obtained by questionnaire in clinical practice and their association with semen quality. J Androl [online] 2009 Sep-Oct, 30(5):566-79 [viewed 20 August 2014] Available from: doi:10.2164/jandrol.108.005918
  12. Fertility. Assessment and treatment for people with fertility problems. NICE clinical guideline 156[online] Issued: February 2013.[viewed on 20 Aug 2014] Available from; http://www.nice.org.uk/guidance/cg156/resources/guidance-fertility-pdf
  13. Fertility. Assessment and treatment for people with fertility problems. NICE clinical guideline 156[online] Issued: February 2013.[viewed on 20 Aug 2014] Available from; http://www.nice.org.uk/guidance/cg156/resources/guidance-fertility-pdf
  14. Fertility. Assessment and treatment for people with fertility problems. NICE clinical guideline 156[online] Issued: February 2013.[viewed on 20 Aug 2014] Available from; http://www.nice.org.uk/guidance/cg156/resources/guidance-fertility-pdf
  15. Fertility. Assessment and treatment for people with fertility problems. NICE clinical guideline 156[online] Issued: February 2013.[viewed on 20 Aug 2014] Available from; http://www.nice.org.uk/guidance/cg156/resources/guidance-fertility-pdf
  16. Fertility. Assessment and treatment for people with fertility problems. NICE clinical guideline 156[online] Issued: February 2013.[viewed on 20 Aug 2014] Available from; http://www.nice.org.uk/guidance/cg156/resources/guidance-fertility-pdf
  17. GUO XC, SEGARS JH. The impact and management of fibroids for fertility: an evidence-based approach. Obstet Gynecol Clin North Am [online] 2012 Dec, 39(4):521-33 [viewed 20 August 2014] Available from: doi:10.1016/j.ogc.2012.09.005
  18. KOCOURKOVA J, BURCIN B, KUCERA T. Demographic relevancy of increased use of assisted reproduction in European countries. Reprod Health [online] 2014 May 26:37 [viewed 20 August 2014] Available from: doi:10.1186/1742-4755-11-37
  19. LEISEGANG K, BOUIC PJ, MENKVELD R, HENKEL RR. Obesity is associated with increased seminal insulin and leptin alongside reduced fertility parameters in a controlled male cohort. Reprod Biol Endocrinol [online] 2014 May 7:34 [viewed 20 August 2014] Available from: doi:10.1186/1477-7827-12-34
  20. NIKBAKHT R, SAHARKHIZ N. The influence of sperm morphology, total motile sperm count of semen and the number of motile sperm inseminated in sperm samples on the success of intrauterine insemination. Int J Fertil Steril [online] 2011 Oct, 5(3):168-73 [viewed 20 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/25101161
  21. PETER N. KOLETTIS, Evaluation of the Subfertile Man. Am Fam Physician.[online] 2003 May 15;67(10):2165-2172.[viewed on 19 Aug 2014] Available from; http://www.aafp.org/afp/2003/0515/p2165.html
  22. PETER N. KOLETTIS, Evaluation of the Subfertile Man. Am Fam Physician.[online] 2003 May 15;67(10):2165-2172.[viewed on 19 Aug 2014] Available from; http://www.aafp.org/afp/2003/0515/p2165.html
  23. PETER N. KOLETTIS, Evaluation of the Subfertile Man. Am Fam Physician.[online] 2003 May 15;67(10):2165-2172.[viewed on 19 Aug 2014] Available from; http://www.aafp.org/afp/2003/0515/p2165.html
  24. ROHRBECK P. Pelvic inflammatory disease among female recruit trainees, active component, U.S. Armed Forces, 2002-2012. MSMR [online] 2013 Sep, 20(9):15-8 [viewed 22 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/24093960
  25. TEMPLETON A, MORRIS JK, PARSLOW W. Factors that affect outcome of in-vitro fertilisation treatment. Lancet [online] 1996 Nov 23, 348(9039):1402-6 [viewed 21 August 2014] Available from: doi:10.1016/S0140-6736(96)05291-9
  26. WDOWIAK A, SULIMA M, SADOWSKA M, GRZEGORZ B, BOJAR I. Alcohol consumption and quality of embryos obtained in programmes of in vitro fertilization. Ann Agric Environ Med [online] 2014, 21(2):450-3 [viewed 19 August 2014] Available from: doi:10.5604/1232-1966.1108623
  27. ZHANG E, ZHANG Y, FANG L, LI Q, GU J. Combined hysterolaparoscopy for the diagnosis of female infertility: a retrospective study of 132 patients in china. Mater Sociomed [online] 2014 Jun, 26(3):156-7 [viewed 20 August 2014] Available from: doi:10.5455/msm.2014.26.156-157