Millions of sperm at coitus → about 1% reach the endocervical canal → only a few thousand reach the Fallopian tube ^[1]

How to read the journey diagram: Attrition occurs at the vagina, cervix and uterotubal junction; fertilization normally occurs in the tubal ampulla. The diagram explains why semen parameters matter, but it does not create a sharp fertile/infertile cut-off—fertile and infertile populations overlap substantially.

Normal fertility in women involves follicle development → ovulation → fertilization in the Fallopian tube → embryo implantation in the endometrium ^[1]

• Follicular phase: FSH recruits a cohort of follicles; one becomes dominant, producing rising oestradiol
• Ovulation: LH surge triggers follicular rupture ~36 hours later
• Luteal phase: Corpus luteum produces progesterone, preparing the endometrium
• Fertilization window: Oocyte viable ~12–24 hours; sperm viable ~3–5 days → fertile window is approximately 6 days ending on the day of ovulation

How to read the cycle diagram: FSH supports follicular growth and rising oestradiol during the proliferative phase. Sustained oestradiol produces the mid-cycle LH surge; follicular rupture follows, and the corpus luteum then secretes progesterone, converting the endometrium to a secretory pattern and raising basal body temperature. After fertilization in the tube, cleavage occurs during transit; the blastocyst reaches the uterine cavity for implantation.

Peak monthly pregnancy rate ~25–30%; cumulative rate at 1 year ~80%; at 2 years ~90% ^[1]

Female: Age, menstrual cycle regularity (21–35 days), history of pelvic infection or surgery, previous investigations and treatment ^[1]

Male: Age/occupation, past health, coital history, smoking/alcohol ^[1]

Why each element matters:

• Age of the woman is the single most important prognostic factor (declining oocyte quality and quantity)
• Menstrual regularity (21–35 days) suggests 95% chance of ovulation ^[1] — this is a key teaching point
• Pelvic infection/surgery → tubal damage risk
• Coital history → frequency, timing, erectile dysfunction (a commonly overlooked cause)
• Smoking → reduces ovarian reserve in women, impairs sperm quality in men
• Occupation (male) → exposure to heat, chemicals, radiation

Female: Body weight, vaginal examination (uterine size, mobility, adnexal mass) ^[1]

Male: Testicular size, vas and epididymis, varicocele (? Necessary = the slide questions whether male exam is always needed) ^[1]

Why body weight? Obesity causes anovulation via excess peripheral oestrogen conversion (aromatase in adipose tissue) and insulin resistance → hyperandrogenism. BMI > 30 significantly reduces IVF success. Conversely, BMI < 18.5 causes hypothalamic amenorrhoea.

Female: > 35 years old, irregular cycles, previous pelvic surgery, previous STD, abnormal pelvic examination ^[1]

Male: Systemic illness, previous genital pathology, previous STD, varicocele, abnormal genital examination ^[1]

Note: The lecture slide lists systemic illness under male early referral criteria ^[1].

For current practice, read the slide's “> 35” as age 35 or older, and do not wait for a time threshold when there is a known condition associated with infertility ^[13].

Serum mid-luteal progesterone levels (a week before next expected period) ^[1]

For irregular cycles: FSH, prolactin, thyroxine, USS ovarian morphology (PCO) ^[1]

For regular cycles: prolactin or thyroxine NOT indicated ^[1]

Current first step: Menstrual history is usually enough: regular 21–35-day cycles generally do not need biochemical confirmation of ovulation. Use luteal progesterone when the history is indeterminate; if cycles are clearly irregular/absent, investigate the cause rather than merely “confirming” anovulation ^[13].

Why mid-luteal? Progesterone is secreted by the corpus luteum ONLY after ovulation. Its peak is approximately 7 days post-ovulation (= mid-luteal). If sampled too early or too late, you'll get a falsely low value. In a 28-day cycle, sample on day 21. In a 35-day cycle, sample on day 28.

Other Tests of Ovulation

The lecture's biphasic BBT graph is physiologically useful—progesterone raises temperature after ovulation—but BBT charts should not be used to confirm or precisely time ovulation because the thermal shift is retrospective and imprecise ^[13][20].

Hypothalamic: weight change (obesity, anorexia nervosa), drugs (tranquillizers), psychological disturbance ^[1]

Pituitary: tumours, Sheehan's syndrome, hyperprolactinaemia ^[1]

Ovary: ovarian insufficiency (chromosomal - Turner Syndrome, surgery, radiotherapy, chemotherapy, mumps), PCOS ^[1]

Other endocrine: thyroid disorders, adrenal disorders ^[1]

Investigation of Anovulation

The slide uses FSH > 25 IU/L as a pointer to ovarian insufficiency; a single result alone is not the diagnosis. ^[1]

Check prolactin for pituitary causes ^[1]

Check for PCOS (USS), thyroid (TFT), Cushing's ^[1]

From first principles: FSH is high in ovarian insufficiency because of the loss of negative feedback from oestradiol and inhibin B. The pituitary "shouts louder" (high FSH) trying to stimulate non-responsive ovaries. Conversely, in hypothalamic/pituitary causes, FSH is low or inappropriately normal despite low oestrogen.

Current POI criteria: In a person younger than 40, diagnose premature ovarian insufficiency from at least 4 months of amenorrhoea/irregular cycles plus biochemical confirmation with FSH > 25 IU/L; repeat FSH after 4–6 weeks if the diagnosis is uncertain ^[21].

Two main methods: Hysterosalpingogram (HSG) and Laparoscopy ^[1]

Hysterosalpingo-contrast-ultrasonography (HyCoSy) may be an alternative to HSG ^[1]

Hydrosalpinx (shown on lecture slides): A blocked, fluid-filled Fallopian tube. Important because hydrosalpinx fluid is embryotoxic and reduces IVF success rates. Current practice: salpingectomy or proximal tubal occlusion before IVF if hydrosalpinx is present.

Reading the Lecture Images

• Normal HSG: contrast outlines the triangular uterine cavity, traverses thin tubes and disperses freely into both peritoneal cavities.
• Proximal block/spasm: abrupt non-filling at the uterotubal junction; cornual spasm can mimic true occlusion, so interpret in clinical context.
• Hydrosalpinx: a dilated, tortuous or club-ended contrast-filled tube with absent free spill, indicating distal occlusion.
• What HSG cannot show well: external endometriotic implants and peritubal adhesions. The laparoscopic photographs show exactly these lesions—dark/red implants, endometriomas and fibrous bands tethering the tube or ovary—while chromopertubation demonstrates spill directly.

In the endometriosis ultrasound images, an endometrioma appears as a well-defined ovarian cyst with fairly homogeneous low-level “ground-glass” echoes. Bilateral endometriomas and adhesions can markedly distort tubo-ovarian anatomy.

Laparoscopy for unexplained infertility, advanced sperm function testing (DNA fragmentation), postcoital testing, thrombophilia testing, immunologic testing, karyotype, endometrial biopsy and prolactin — NOT routine without a specific indication. ^[1][13][14]

0.4 mg folic acid whilst trying to conceive and during the first 12 weeks of pregnancy to prevent neural tube defects ^[1]

Reduce body weight in obese women ^[1]

Stop smoking, stop alcohol ^[1]

Stop smoking, avoid excessive alcohol ^[1]

Men with poor quality sperm advised to wear loose fitting underwear and trousers, and avoid occupational or social situations that might cause testicular hyperthermia ^[1]

Evidence qualifier: Avoiding sustained testicular heat is biologically plausible and low risk, but the evidence for most lifestyle/environmental interventions—including a specific underwear style—is limited. Do not present loose clothing as a proven fertility treatment ^[14].

Options: Tubal surgery vs IVF. Decision depends on: (1) The lesions, (2) The infertile couple, (3) The medical service ^[1]

Tubal surgery: microsurgical technique, laparotomy or laparoscopy. Types: adhesiolysis, re-anastomosis, salpingostomy ^[1]

When to choose surgery vs IVF:

• Mild distal tubal disease → surgery may be reasonable (cumulative pregnancy rate over multiple cycles)
• Severe tubal disease/bilateral hydrosalpinx → IVF preferred
• Reversal of sterilization → surgery if ≥4 cm of healthy tube remains
• Older woman or additional male factor → go straight to IVF

Minimal/mild endometriosis: ovarian-suppression treatment does NOT enhance fertility. Operative laparoscopy, ovarian stimulation + IUI, and IVF are possible pathways. ^[1][22]

Current nuance: ESHRE strongly advises against ovarian suppression solely to improve fertility. Operative laparoscopy may be offered for rASRM stage I/II disease (weak recommendation); the decision should account for pain, age, ovarian reserve, prior surgery, other infertility factors and patient preference. Endometrioma surgery may reduce ovarian reserve, so “ablate all visible disease” is not an automatic rule ^[22].

Historical slide message: expectant management; no clomiphene alone or unstimulated IUI; IVF for persistent infertility. ^[1]

Investigate cause and treat: psychotherapy, drugs for erectile dysfunction (e.g., Viagra). IUI by husband's sperm at time of ovulation. ^[1]

Sexual dysfunction and infertility overlap: Studies show 32.5% of subfertile women attending fertility clinics have sexual dysfunction ^[8]. Infrequent coitus → reduced exposure to sperm → infertility. Always ask about coital frequency and sexual function as part of fertility assessment.

Increases motile sperm in uterus through IUI around ovulation. Ovarian stimulation increases oocytes available. Pregnancy rate ~10% per cycle. ^[1]

How IUI works: Semen is washed and prepared (removing prostaglandins, debris and immotile sperm) → a thin transcervical catheter deposits concentrated motile sperm high in the uterine cavity around ovulation → sperm still travel through a Fallopian tube for in-vivo fertilization, so at least one functioning patent tube is generally required. If stimulation is used, oral agents or carefully monitored low-dose gonadotrophins may recruit additional follicles; excessive follicle recruitment should trigger cycle cancellation rather than accepting a high multiple-pregnancy risk ^[17].

The 2020 SAQ tested surrogacy ethics ^[9]:

• Gestational surrogacy (embryo implanted in surrogate who has no genetic relationship) vs traditional surrogacy (surrogate's own oocyte)
• Ethical challenges: commodification of reproduction, exploitation of surrogates, legal parentage, psychological impact on surrogate/child, consent issues
• Arguments supporting: reproductive autonomy, fulfilling desire for genetically related child

The 2022 SAQ tested oocyte freezing and donor sperm ethics ^[10]:

• Storage duration of oocytes in HK: 10 years (extendable under certain conditions)
• Ethical concerns: welfare of the unborn child, social vs medical egg freezing, single parenthood
• Donor sperm ethical objections: anonymity issues, commodification, welfare of child, right to know genetic origin

Hyperprolactinaemia ^[3][4][7]: Prolactin inhibits GnRH → hypogonadotrophic hypogonadism → anovulation in women, impotence/infertility in men. Causes include prolactinoma, drugs (antipsychotics, antiemetics), hypothyroidism (↑TRH). Treatment: dopamine agonists (bromocriptine, cabergoline).

Turner Syndrome (45,X) ^[6]: Ovarian dysgenesis → primary ovarian insufficiency → high FSH, streak gonads. Pregnancy only possible with donor oocyte IVF.

Klinefelter Syndrome (47,XXY) ^[3]: Small firm testes, azoospermia, tall stature, gynaecomastia. High FSH, low testosterone. Micro-TESE may rarely retrieve sperm for ICSI.

Chlamydia trachomatis is the most common bacterial cause of PID → tubal damage → infertility, ectopic pregnancy ^[11][12]. Gonorrhoea can also cause PID and infertility. This is why previous STD history is a red flag for tubal factor infertility and warrants laparoscopy over HSG.