Pelvic Pain During Early Pregnancy

ByEmily E. Bunce, MD, Wake Forest School of Medicine;
Robert P. Heine, MD, Wake Forest School of Medicine
Reviewed/Revised Jul 2023
View Patient Education

Pelvic pain is common during early pregnancy and may accompany serious or minor disorders. Some conditions causing pelvic pain also cause vaginal bleeding. In some of these disorders (eg, ruptured ectopic pregnancy, ruptured hemorrhagic corpus luteum cyst), bleeding may be severe, sometimes leading to hemorrhagic shock.

Causes of upper and generalized abdominal pain are similar to those in nonpregnant patients.

Etiology

Causes of pelvic pain during early pregnancy (see table Some Causes of Pelvic Pain) may be

  • Obstetric

  • Gynecologic

  • Nongynecologic

Sometimes no particular etiology is identified.

The most common obstetric causes of pelvic pain during early pregnancy are

  • Normal changes of pregnancy

  • Spontaneous abortion (threatened, inevitable, incomplete, complete, missed, or septic)

The most common serious obstetric cause is

Gynecologic causes include adnexal torsion, which is more common during pregnancy because the corpus luteum causes the ovaries to enlarge, increasing the risk of the ovary twisting around its pedicle.

Common nongynecologic causes include various common gastrointestinal and genitourinary disorders:

During late pregnancy, pelvic pain may result from labor, obstetric complication, or one of the many nonobstetric causes of pelvic pain.

Table
Table

Evaluation

Evaluation of patients with pelvic pain during early pregnancy should exclude potentially serious treatable causes (eg, ruptured or unruptured ectopic pregnancy, septic abortion, appendicitis).

History

History of present illness should include the estimated due date (and whether this is based on last menstrual period or ultrasonography), any risk factors for obstetric complications, and prior testing or complications during the current pregnancy. It should include any events associated with the onset of the pain (eg, physical trauma) and characteristics of the pain: onset (sudden or gradual), location (localized or diffuse), character (crampy, colicky, or sharp), pattern (constant or intermittent), and effect of movement. Any fever, chills, or vaginal bleeding or discharge should be noted. A history of self-induced or illegal termination of pregnancy suggests septic abortion, but absence of this history does not exclude this diagnosis.

Review of systems should include genitourinary and gastrointestinal symptoms that suggest a cause.

Important genitourinary symptoms and suggested etiologies include

Important gastrointestinal symptoms and suggested etiologies include

Past medical history should include gravidity (number of confirmed pregnancies), parity (number of term and preterm deliveries) and number of abortions (spontaneous or induced), and questions relevant to disorders known to cause pelvic pain (eg, inflammatory bowel disease, irritable bowel syndrome, nephrolithiasis, ectopic pregnancy, spontaneous abortion). Risk factors for these disorders should be identified.

The most significant risk factors for ectopic pregnancy include

  • Previous ectopic pregnancy (the most important)

  • Previous abdominal surgery (especially tubal surgery, eg, tubal ligation)

  • Tubal abnormalities (eg, hydrosalpinx)

  • Current use of intrauterine device

  • In vitro fertilization in current pregnancy

Additional risk factors for ectopic pregnancy include history of sexually transmitted infection or pelvic inflammatory disease, current use of estrogen/progestin oral contraceptives, cigarette smoking, infertility, and prior spontaneous or induced abortion.

Risk factors for spontaneous abortion include

  • Age > 35

  • History of spontaneous abortion

  • Cigarette smoking

  • Uterine abnormalities (eg, leiomyoma, adhesions)

Risk factors for bowel obstruction include

  • Previous abdominal surgery

  • Hernia

  • Intraabdominal malignancy

Physical examination

Evaluation of patients during pregnancy should include routine prenatal evaluation to assess maternal and fetal status, including

  • Assessment of maternal vital signs

  • Abdominal examination for fundal height

  • Sometimes, pelvic examination

  • Evaluation of fetal status with fetal heart rate auscultation

  • Sometimes pelvic ultrasonography (depending on symptoms and gestational age)

Physical examination directed at evaluating pelvic pain includes noting whether vital signs indicate fever and signs of hypovolemia (hypotension, tachycardia).

The abdomen is palpated for tenderness, peritoneal signs (rebound, rigidity, guarding), and uterine size and is percussed for tympany.

Pelvic examination includes inspection of the cervix for discharge, dilation, and bleeding. Vaginal or cervical discharge, if present, should be sampled and tested for infection, if vaginitis or cervicitis is suspected.

Bimanual examination should check for cervical motion tenderness, adnexal masses or tenderness, and uterine size. If ectopic pregnancy is suspected, pelvic examination should be done carefully without placing excess pressure on the adnexa, which could cause rupture of a tubal pregnancy.

Red flags

The following findings are of particular concern:

  • Hemodynamic instability (hypotension, tachycardia, or both)

  • Syncope or near syncope

  • Peritoneal signs (rebound, rigidity, guarding)

  • Fever, chills, and/or purulent vaginal discharge

  • Vaginal bleeding

Interpretation of findings

Certain findings suggest causes of pelvic pain but are not always diagnostic (see table Some Causes of Pelvic Pain).

For all women who present with pelvic pain during early pregnancy, the most serious cause—ectopic pregnancy—must be excluded, regardless of any other findings. Nonobstetric causes of pelvic pain (eg, acute appendicitis) must always be considered and investigated as in nonpregnant women.

As in any patient, findings of peritoneal irritation (eg, focal tenderness, guarding, rebound, rigidity) are a concern. Common causes include appendicitis, ruptured ectopic pregnancy, and, less often, ruptured ovarian cyst. However, absence of peritoneal irritation does not rule out such disorders, and index of suspicion must be high.

Findings that suggest a cause include

  • Vaginal bleeding accompanying the pain: Spontaneous abortion or ectopic pregnancy

  • An open cervical os or tissue passed through the cervix or vagina: Generally, an inevitable, incomplete, or complete abortion

  • Presence of fever, chills, and a purulent vaginal discharge: Septic abortion (particularly in patients with a history of instrumentation of the uterus or illicitly attempted termination of pregnancy)

Pelvic inflammatory disease is rare during pregnancy but may occur.

Testing

If an obstetric cause of pelvic pain is suspected, quantitative measurement of beta-hCG and complete blood count should be done,

If the patient also has vaginal bleeding or suspected internal bleeding, blood type and Rh typing are done. If there is hemodynamic instability (with hypotension, persistent tachycardia, or both), blood should be cross-matched, and fibrinogen level, fibrin split products, and prothrombin time/partial thromboplastin time (PT/PTT) are determined.

Pelvic ultrasonography is done to confirm an intrauterine pregnancy and to evaluate for

  • Fetal heartbeat, size, and movement

  • Uterine pathology

  • Fallopian tube or ovarian mass or other abnormalities

  • Free fluid in the pelvis

Both transabdominal and transvaginal ultrasonography should be used as necessary. If the uterus is empty and the patient has not noted passage of tissue from the vagina, ectopic pregnancy is suspected. If Doppler ultrasonography shows that blood flow to the adnexa is absent or decreased, adnexal (ovarian) torsion is suspected. However, this finding is not always present because spontaneous detorsion can occur.

However, ultrasonography can and should be deferred, as needed, to expedite surgical treatment in the hemodynamically unstable patient with a positive pregnancy test, given the very high likelihood of either ectopic pregnancy or spontaneous abortion with hemorrhage.

Laparoscopy can be used to diagnose pain that remains significant and undiagnosed after the usual evaluation.

Treatment

Treatment of pelvic pain during early pregnancy is directed at the cause.

If ectopic pregnancy

Treatment of spontaneous abortion

Women who have an Rh-negative blood type and have vaginal bleeding or an ectopic pregnancy should be given Rho(D) immune globulin to prevent alloimmunization.

Ruptured corpus luteum cysts and degeneration of a uterine fibroid are treated conservatively with oral analgesics.

Treatment of adnexal torsion is surgical:

  • If the ovary is viable: Manual detorsion

  • If the ovary is infarcted and nonviable: Oophorectomy or salpingectomy

Key Points

  • Pelvic pain in early pregnancy should always raise concern for ectopic pregnancy.

  • Consider nonobstetric etiologies as a cause of acute abdomen during pregnancy.

  • If no clear nonobstetric cause is identified, ultrasonography is usually necessary.

  • Suspect a septic abortion when there is a history of recent uterine instrumentation or induced abortion.

  • Determine blood type and Rh status for all women during early pregnancy; if heavy vaginal bleeding or ectopic pregnancy occurs, all women with Rh-negative blood should be given Rho(D) immune globulin.

Drugs Mentioned In This Article
quizzes_lightbulb_red
Test your KnowledgeTake a Quiz!
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID