BASICS
- Definition: Failure to conceive after 12 months of regular unprotected intercourse.
- Evaluation: Start at 6 months if woman >35 years; immediate if >40 years.
- Types: Primary (never pregnant), Secondary (previous pregnancy).
EPIDEMIOLOGY
- Fertility declines starting early 30s, accelerates late 30s.
- 85% couples conceive within 12 months; 95% within 24 months.
- ~12.7% of reproductive-age women seek infertility treatment annually in the US.
- Prevalence: 8.8% of US women aged 15-49 affected.
- Higher infertility rates in women >35 years.
ETIOLOGY AND PATHOPHYSIOLOGY
- ~85% due to identifiable causes: tubal disease, ovulatory dysfunction, male factor.
- Acquired causes: PID (most common), endometriosis, PCOS, premature ovarian failure.
- 25% due to ovulatory disorders (PCOS, hyperprolactinemia, thyroid disease, etc.).
- Diminished ovarian reserve (DOR): low oocyte quantity/quality.
- Congenital/genetic abnormalities: Klinefelter syndrome, Turner syndrome, fragile X, Y chromosomal microdeletions, CFTR mutations.
RISK FACTORS
Female
- Gynecologic: irregular menses, STIs, fibroids, dysmenorrhea.
- Medical: advanced age, endocrinopathies, autoimmune disease, obesity, cancer.
- Surgical: appendicitis, pelvic/intrauterine surgery, tubal ligation.
- Social: smoking, alcohol/substance use, eating disorders, delayed childbearing.
Male
- Medical: STIs, prostatitis, endocrinopathy, cancer.
- Surgical: orchiopexy, hernia repair, vasectomy/reversal.
- Social: smoking, alcohol/substance abuse, anabolic steroids, environmental heat exposure.
COMMONLY ASSOCIATED CONDITIONS
- Pelvic pathology, endocrine dysfunction, anovulation (e.g., PCOS).
DIAGNOSIS
HISTORY
- Reproductive history, menstrual cycles, sexual function.
- Prior pregnancies, abortions, surgeries.
- STI, malignancy, chronic illness.
- Family reproductive issues.
- Medications and environmental exposures.
PHYSICAL EXAM
- BMI, fat distribution, waist circumference.
- Female: Tanner staging, PCOS signs, vaginal and uterine exam.
- Male: genital exam (penis, testes, vas deferens, varicocele).
DIFFERENTIAL DIAGNOSIS
- Kallmann syndrome, hypogonadotropic hypogonadism, hormonal deficiencies, hemochromatosis, endometriosis, thyroid disease, prolactinoma, PCOS.
DIAGNOSTIC TESTS
Initial Tests
- Ovulation assessment: basal body temperature, LH surge testing, progesterone levels.
- Ovarian reserve: day 3 FSH, estradiol, AMH, antral follicle count.
- Semen analysis: volume, concentration, motility, morphology; repeat 2-3 times.
- Additional labs: prolactin, TSH, 17-hydroxyprogesterone, androgens.
- Infectious disease screening: HIV, HSV, chlamydia, gonorrhea, RPR, hepatitis B, CMV.
- Imaging: transvaginal US, hysterosalpingogram (HSG).
Follow-Up
- Hysteroscopy and laparoscopy for anatomical abnormalities or endometriosis.
TREATMENT
GENERAL MEASURES
- Lifestyle: ideal BMI, smoking cessation, limit caffeine/alcohol.
- Timing intercourse around ovulation.
- Folate supplementation (0.4-0.8 mg/day) for all women.
- Male diet: carotenoids may improve sperm quality.
Assisted Reproductive Techniques
- IVF: egg retrieval, fertilization outside body, embryo transfer.
- IUI: sperm placed directly into uterus; success 7-10% per cycle.
- ICSI: single sperm injected into egg for severe male factor.
MEDICATIONS
First Line
- Women with anovulation:
- Hypogonadotropic: daily FSH/LH injections.
- Normogonadotropic (mostly PCOS): letrozole preferred over clomiphene.
- Unexplained infertility: controlled ovarian hyperstimulation, IUI, IVF.
- Male: lifestyle, discontinue offending meds, clomiphene to improve sperm count.
Second Line
- Metformin for PCOS with glucose intolerance.
- Oral contraceptives for certain anovulatory cases.
- Dopamine agonists (cabergoline, bromocriptine) for hyperprolactinemia.
- Gonadotropins for clomiphene-resistant or hypogonadotropic patients.
ISSUES FOR REFERRAL
- To reproductive endocrinologists and urologists.
- Consider surrogate pregnancy if female cannot conceive.
SURGERY/OTHER PROCEDURES
- For anatomical causes: polypectomy, myomectomy, salpingectomy.
- Male surgery: varicocele repair, vasectomy reversal, sperm retrieval.
- Ovarian drilling/wedge resection for PCOS.
ONGOING CARE
- Refer if no success after 3-6 cycles of oral ovulation induction.
DIET
- Limit caffeine and alcohol intake.
PATIENT EDUCATION
- American Society for Reproductive Medicine: https://www.asrm.org
- Resolve: The National Infertility Association: https://www.resolve.org
PROGNOSIS
- 80-90% of couples conceive within 12 months of trying.
- Fertility declines with age.
COMPLICATIONS
- Anxiety, multiple pregnancies, ovarian hyperstimulation syndrome (OHSS).
- Slightly increased risk of congenital anomalies.
- Higher maternal morbidity in infertile women and those receiving fertility treatments.
REFERENCES
- Carson SA, Kallen AN. Diagnosis and management of infertility: a review. JAMA. 2021;326(1):65-76.
ICD10
- N97.9 Female infertility, unspecified
- N46.9 Male infertility, unspecified
- N97.1 Female infertility of tubal origin
CLINICAL PEARLS
- Infertility is often multifactorial and requires a comprehensive approach.