The appearance of blood in your urine, medically termed hematuria, is an unsettling symptom that warrants prompt medical attention, particularly during pregnancy. Hematuria can manifest as visibly red or pink urine (gross hematuria) or as microscopic amounts detectable only through laboratory testing. While this symptom causes anxiety, it signals the need for immediate medical evaluation. Investigating the source of the bleeding is necessary to protect both maternal and fetal health.
When to Seek Medical Attention Immediately
Noticing any change in the color of your urine requires an immediate call to your obstetrician or midwife for guidance. Certain accompanying symptoms, however, signal a potential emergency requiring a visit to the nearest emergency department without delay. Severe pain in the lower back, abdomen, or flank suggests a serious issue like a kidney stone or severe infection.
Fever and chills combined with blood in the urine can indicate pyelonephritis, a kidney infection that requires prompt treatment. Additionally, the inability to pass urine or passing urine with large blood clots represents an obstruction requiring urgent intervention. Any instance of heavy bleeding, whether accompanied by pain or not, should be evaluated immediately.
Underlying Causes of Blood in Urine
The most frequent cause of hematuria in pregnant patients is a urinary tract infection (UTI), ranging from a simple bladder infection to a kidney infection. Pregnancy increases the risk for UTIs because the growing uterus puts pressure on the bladder and ureters, impeding urine flow and allowing bacteria to multiply. Hormonal changes also contribute by causing the ureters to dilate and the urinary tract muscles to relax, further slowing urine movement.
A lower-tract infection (cystitis) involves bladder lining inflammation, which can cause small blood vessels to rupture and result in visible blood. If the infection travels up to the kidneys, it becomes pyelonephritis, a serious condition associated with fever and flank pain.
Another common cause is the formation or passage of kidney or bladder stones. Pregnancy can exacerbate these stones due to changes in mineral metabolism and the potential for them to become lodged as the uterus displaces the ureters. Moving stones can scrape the urinary tract lining, causing pain and bleeding.
Less common reasons include structural changes or increased vascularity of the urinary tract. Increased blood flow to the pelvic region can make blood vessels more fragile and susceptible to mild trauma. Rarely, hematuria can signal kidney disease or temporary compression of the renal vein by the enlarged uterus, which resolves after delivery.
Identifying the Source Through Safe Testing
Identifying the precise source of bleeding begins with diagnostic testing tailored to minimize risk to the developing fetus. The initial step is a urinalysis to determine the concentration of blood cells and check for signs of infection. This is followed by a urine culture, which diagnoses bacterial infection and identifies the specific strain.
Blood work is often performed concurrently to assess kidney function and check for systemic signs of infection. If infection is ruled out, or if pain suggests a stone, imaging is necessary. The primary tool used is the renal and pelvic ultrasound, which is safe because it relies on sound waves rather than radiation. Ultrasound allows physicians to visualize the kidneys, ureters, and bladder for stones, structural abnormalities, or obstruction.
Advanced imaging like computerized tomography (CT) scans and X-rays are avoided during pregnancy due to the risk of fetal radiation exposure. In complex cases where ultrasound is inconclusive, magnetic resonance urography (MRU) without contrast may be considered. The diagnostic strategy prioritizes non-invasive, radiation-free methods.
Managing and Treating the Condition While Pregnant
Once a diagnosis is confirmed, treatment focuses on resolving the underlying issue using methods safe during pregnancy. For a urinary tract infection, standard treatment involves a course of pregnancy-safe antibiotics. Commonly prescribed options include amoxicillin-clavulanate or cephalexin; nitrofurantoin is frequently used in the second trimester.
Certain antibiotics, such as trimethoprim-sulfamethoxazole, are avoided in the first and late third trimesters due to potential fetal risks.
If hematuria is caused by a kidney stone, initial management is conservative, focusing on pain control with approved analgesics and hydration to encourage natural passage. Most symptomatic stones in pregnant patients pass spontaneously with this approach.
If conservative management fails, or if the stone causes obstruction or uncontrolled infection, a procedure may be necessary. This intervention typically involves placing a ureteral stent to bypass the obstruction or performing a ureteroscopy to remove the stone. Consistent follow-up testing, including repeat urine cultures and urinalysis, is performed to ensure the infection or obstruction has fully cleared.