Infertility

Infertility is defined as the inability to conceive after 12 months of regular, unprotected sexual intercourse in women under 35 years, or after 6 months in women 35 years or older, affecting either the female, male, or both partners.

Definition

Infertility is defined as the inability to conceive after 12 months of regular, unprotected sexual intercourse in women under 35 years, or after 6 months in women 35 years or older, affecting either the female, male, or both partners.

Epidemiology

Affects approximately 10–15% of couples worldwide.
Female factors account for about 40–50%, male factors 30–40%, and combined or unexplained causes 10–20%.
Risk increases with advanced maternal age, obesity, smoking, and certain chronic illnesses.
Infertility prevalence is higher in low-resource settings due to untreated infections and limited access to care.

Etiology

Female factors: ovulatory disorders, tubal obstruction, endometriosis, uterine abnormalities, cervical factors.
Male factors: low sperm count, poor motility, abnormal morphology, hormonal disorders, genetic defects, varicocele.
Unexplained infertility: normal evaluations in both partners.
Lifestyle and environmental factors: smoking, alcohol, obesity, stress, occupational exposures.
Iatrogenic factors: pelvic surgery, chemotherapy, radiation.

Pathophysiology

Disruption of ovulation, fertilization, or implantation.
Tubal damage impairs egg transport to the uterus.
Endometrial or cervical abnormalities interfere with implantation or sperm migration.
Sperm defects reduce fertilization capability.
Hormonal imbalances (FSH, LH, prolactin, thyroid hormones) alter reproductive function.