Ectopic Pregnancy

Ectopic pregnancy is the implantation of a fertilized ovum outside the uterine cavity, most commonly in the fallopian tube, leading to a potentially life-threatening condition if untreated.

Definition

Ectopic pregnancy is the implantation of a fertilized ovum outside the uterine cavity, most commonly in the fallopian tube, leading to a potentially life-threatening condition if untreated.

Epidemiology

Occurs in approximately 1–2% of all pregnancies.
Most common in women aged 25–34 years.
Risk higher in women with prior pelvic infection, tubal surgery, or infertility treatments.
Leading cause of maternal morbidity and mortality in the first trimester.
Incidence rising due to assisted reproductive technologies and increased detection.

Etiology

Tubal damage from pelvic inflammatory disease (Chlamydia, Gonorrhea).
Previous tubal surgery or sterilization failure.
Endometriosis or pelvic adhesions.
Use of intrauterine devices (IUD) does not increase risk but ectopic pregnancy more likely if pregnancy occurs.
Assisted reproductive technologies and ovulation induction.

Pathophysiology

Fertilized ovum fails to reach the uterine cavity and implants in ectopic site, most commonly fallopian tube (ampulla, isthmus).
Growth leads to tubal distension, ischemia, and risk of rupture.
Hemorrhage occurs with rupture, causing hemoperitoneum and hypovolemic shock.
In rare cases, implantation can occur in ovary, cervix, or abdominal cavity.
Progesterone and hCG support early ectopic development but insufficient for full-term gestation.