ABOG Reproductive Endocrinology and Infertility cheat sheet

GnRH is released in pulsatile fashion from hypothalamic neurons; continuous GnRH exposure downregulates pituitary GnRH receptors and suppresses gonadotropins.

Gonadotropin secretion is governed by pulsatility: rapid pulses favor LH, slower pulses favor FSH.

Estradiol feedback is biphasic: negative feedback at low/moderate levels and positive feedback at sustained high preovulatory levels triggering the LH surge.

Inhibin B from small antral follicles selectively suppresses FSH; inhibin A from the dominant follicle rises in the late follicular phase.

Progesterone from the corpus luteum raises basal body temperature via central thermoregulatory effects and thickens cervical mucus.

Prolactin suppresses GnRH; hyperprolactinemia causes hypogonadotropic hypogonadism and is treated with dopamine agonists.

Anti-Müllerian hormone from granulosa cells inhibits primordial follicle recruitment and serves as an ovarian reserve marker.

Kisspeptin neurons in the arcuate nucleus are upstream regulators of GnRH pulse generation.

WHO 2022 anovulation classification: Type I hypothalamic, Type II normogonadotropic (PCOS), Type III ovarian insufficiency, Type IV other/functional.

PCOS Rotterdam criteria require 2 of 3: oligo/anovulation, clinical or biochemical hyperandrogenism, polycystic ovaries.

Menstrual cycle length 21-35 days is normal; cycles >35 days suggest oligo-ovulation.

Ovulation induction first-line in PCOS is letrozole; metformin is adjunctive, especially with insulin resistance.

Hypothalamic amenorrhea shows low FSH, low LH, low estradiol, and is treated with pulsatile GnRH or gonadotropins, not clomiphene.

Progesterone challenge test: withdrawal bleeding indicates estrogenized endometrium and outflow tract patency.

Primary ovarian insufficiency is defined as amenorrhea with FSH >40 mIU/mL before age 40.

Heavy menstrual bleeding is quantified as >80 mL per cycle; structural causes are classified by PALM-COEIN.

Infertility is failure to conceive after 12 months of regular unprotected intercourse; evaluate earlier if age ≥35 or known risk factors.

Standard evaluation includes semen analysis, ovulation assessment, tubal patency (HSG), and ovarian reserve testing.

Day 3 FSH, estradiol, and AMH estimate ovarian reserve; AMH is cycle-independent.

IVF success declines with age, driven largely by aneuploidy rates in oocytes.

Controlled ovarian hyperstimulation risk includes ovarian hyperstimulation syndrome, marked by hemoconcentration and third-spacing.

OHSS prevention: GnRH antagonist protocol with GnRH agonist trigger in high responders, plus freeze-all strategy.

ICSI is indicated for severe male factor, prior fertilization failure, and preimplantation genetic testing cycles.

Intrauterine insemination is generally offered for mild male factor, cervical factor, or unexplained infertility before IVF.

WHO 2021 semen reference limits: volume ≥1.4 mL, concentration ≥16 million/mL, total motility ≥42%, progressive motility ≥30%, normal morphology ≥4%.

Azoospermia is obstructive or nonobstructive; FSH is typically elevated in nonobstructive and normal/low in obstructive.

Varicocele is the most common correctable cause of male infertility; repair may improve semen parameters.

Klinefelter syndrome (47,XXY) causes nonobstructive azoospermia with small firm testes and elevated FSH.

Y chromosome microdeletions: AZFc deletions may permit sperm retrieval; AZFa/AZFb deletions carry poor prognosis.

Sperm retrieval options include TESE, micro-TESE, PESA, and TESA depending on obstruction status.

Hypogonadotropic hypogonadism in men is treated with gonadotropins or pulsatile GnRH to restore spermatogenesis.

Retrograde ejaculation produces low-volume ejaculate with post-ejaculate urinalysis showing sperm.

Early pregnancy loss is pregnancy loss before 10 weeks; most are chromosomally abnormal.

Recurrent pregnancy loss is conventionally defined as ≥2 or ≥3 consecutive losses, depending on guideline.

Antiphospholipid syndrome is a treatable cause; treat with low-dose aspirin plus prophylactic heparin.

Management options for early pregnancy loss: expectant, medical (misoprostol), or surgical (suction dilation and curettage).

Ectopic pregnancy is diagnosed by transvaginal ultrasound and serial β-hCG; treat with methotrexate or surgery.

Methotrexate is contraindicated with intrauterine pregnancy, breastfeeding, or significant renal/hepatic disease.

Anembryonic gestation and embryonic demise are distinct ultrasound categories of early pregnancy failure.

Parental karyotyping is indicated when products of conception show balanced translocations or recurrent losses occur.

Menopause is diagnosed clinically after 12 months of amenorrhea; FSH is not required for diagnosis.

Perimenopause features variable cycle length and vasomotor symptoms; contraception remains necessary until menopause confirmed.

Systemic hormone therapy is the most effective treatment for vasomotor symptoms.

Estrogen alone is used after hysterectomy; combined estrogen-progestogen is required with a uterus to prevent endometrial hyperplasia.

Transdermal estrogen has less venous thromboembolism risk than oral estrogen.

Hormone therapy is not recommended for primary prevention of cardiovascular disease or dementia.

Genitourinary syndrome of menopause responds to local vaginal estrogen, which carries minimal systemic absorption.

Osteoporosis prevention includes calcium, vitamin D, weight-bearing exercise, and pharmacologic therapy when indicated.

Müllerian anomalies include unicornuate, didelphys, bicornuate, septate, and arcuate uteri; septate uterus is associated with recurrent loss.

Imperforate hymen presents with cyclic pelvic pain and bulging membrane in puberty; treat with hymenotomy.

Transverse vaginal septum causes hematocolpos; distinguish from imperforate hymen by anatomy.

Mayer-Rokitansky-Küster-Hauser syndrome: 46,XX with Müllerian agenesis, primary amenorrhea, and normal ovaries.

Androgen insensitivity syndrome: 46,XY with absent uterus, blind vaginal pouch, and testes; testosterone is elevated.

Primary amenorrhea evaluation includes karyotype, FSH, and pelvic imaging when puberty fails to progress by age 15.

Precocious puberty is breast or pubic hair development before age 8; evaluate with bone age, LH, and imaging.

Ovarian torsion in adolescents presents with acute unilateral pain and requires prompt surgical detorsion.

PGT-A screens for aneuploidy; PGT-M tests for monogenic disorders; PGT-SR detects structural rearrangements.

Preimplantation genetic testing requires trophectoderm biopsy at the blastocyst stage.

Mosaicism in PGT results reflects a mixture of euploid and aneuploid cells in the biopsy.

Carrier screening is offered for cystic fibrosis, spinal muscular atrophy, fragile X, and hemoglobinopathies.

Balanced translocations increase risk of unbalanced gametes and recurrent pregnancy loss.

Aneuploidy risk rises with maternal age, primarily due to meiotic nondisjunction.

Noninvasive prenatal testing can be performed from maternal blood after 10 weeks.

Genetic counseling precedes testing and addresses results, reproductive options, and implications for relatives.

Combined hormonal contraception prevents ovulation by suppressing the LH surge and thickening cervical mucus.

Estrogen-containing contraception is contraindicated with migraine with aura, smoking over age 35, and history of VTE.

Progestin-only methods include pills, implant, injectable, and levonorgestrel IUD.

Copper IUD is nonhormonal and causes a spermicidal inflammatory endometrial reaction.

Emergency contraception: copper IUD most effective; levonorgestrel and ulipristal are oral options.

Pelvic inflammatory disease is treated with broad-spectrum antibiotics covering gonorrhea and chlamydia.

Chlamydia screening is recommended annually for sexually active women under age 25.

Bacterial vaginosis is characterized by clue cells and a fishy odor with amine whiff test.

Oocyte and embryo cryopreservation require controlled ovarian stimulation and carry a time delay.

Ovarian tissue cryopreservation is an option for prepubertal patients and those needing urgent treatment.

GnRH agonist cotreatment during chemotherapy may reduce ovarian toxicity.

Sperm cryopreservation should be offered before gonadotoxic therapy in males.

Ovarian transposition (oophoropexy) protects ovaries from pelvic radiation.

Alkylating agents carry the highest gonadotoxicity risk among chemotherapeutics.

Fertility preservation counseling should occur before initiating gonadotoxic treatment whenever feasible.

Ovarian reserve after cancer treatment is assessed with AMH and menstrual history.

Laparoscopic cystectomy for endometrioma should preserve ovarian cortex to limit follicle loss.

Myomectomy improves fertility outcomes for submucosal fibroids; intramural fibroids may benefit from removal.

Hysteroscopic polypectomy and myomectomy treat structural causes of abnormal uterine bleeding and infertility.

Tubal surgery for hydrosalpinx: salpingectomy before IVF improves implantation outcomes.

Adhesiolysis for Asherman syndrome restores cavity; recurrence is prevented with postoperative estrogen and barrier methods.

Endometriosis stage does not correlate directly with pain or fertility outcomes.

Laparoscopy is preferred for ectopic pregnancy when hemodynamically unstable or ruptured.

Robotic and laparoscopic approaches reduce recovery time versus laparotomy for benign gynecologic surgery.

Informed consent for ART must cover risks, alternatives, success rates, and disposition of embryos.

Embryo disposition options include transfer, donation to research, donation to another couple, or discard per patient directive.

Conflict of interest disclosure is required for research and clinical decision-making.

Equitable access to fertility care raises distributive justice considerations.

Quality improvement uses plan-do-study-act cycles and tracking of clinical outcomes.

Root cause analysis reviews adverse events to identify system-level failures.

Maintenance of certification requires ongoing learning and practice assessment.

Patient autonomy governs reproductive decisions, including refusal of treatment.