Why You Pee A Lot During Pregnancy: What’s Normal and What’s Not
Pregnancy brings many changes to your body. One of the earliest and most persistent may be the increased need to urinate.
For many pregnant individuals, frequent bathroom trips can begin as early as the first trimester and continue until delivery. But how do you know if this is just a normal part of pregnancy or a sign that something else is going on?
As a pelvic floor physical therapist, I see many clients who are unsure whether their urinary frequency is expected or problematic. The answer lies in understanding the complex interplay between pregnancy hormones, anatomy, and pelvic floor health.
Why Does Urinary Frequency Increase in Pregnancy?
Increased urination during pregnancy is largely due to hormonal changes and physical pressure from a growing uterus. Early in pregnancy, rising levels of progesterone and human chorionic gonadotropin (hCG) increase renal blood flow.
This boosts the glomerular filtration rate by up to 50%, meaning your kidneys are working harder and producing more urine well before your baby starts pressing on your bladder.
As the uterus enlarges, even as early as the first few weeks, it starts to compress the bladder, decreasing its capacity.
In the first trimester, this can lead to a hypersensitive bladder that triggers the urge to urinate more frequently. By the second trimester, the uterus lifts higher into the abdomen, often relieving some of this pressure temporarily. However, in the third trimester, as the baby's head moves deeper into the pelvis, bladder compression returns, and frequency increases again.
In addition, your blood volume increases by 30–50% during pregnancy to support the developing fetus. Your body needs to manage this extra fluid, and the kidneys play a major role in this process, again contributing to increased urination.
When Is Frequent Urination Not Normal?
Although frequent urination is expected during pregnancy, certain symptoms suggest a need for medical evaluation.
If you experience burning or pain during urination, cloudy or foul-smelling urine, fever, or lower back pain, these could be signs of a urinary tract infection (UTI). UTIs are common during pregnancy and, if untreated, can lead to complications like kidney infections or preterm labor.
Another red flag is excessive urination accompanied by unusual thirst or large volumes of urine. These symptoms may indicate gestational diabetes, which typically develops in the second or third trimester and requires timely screening and management.
Additionally, if you feel like you're not emptying your bladder completely, are leaking urine involuntarily, or are waking up several times at night to urinate (a condition called nocturia), these symptoms could point to pelvic floor dysfunction or bladder irritability, which are both treatable.
The Pelvic Floor Perspective
Your pelvic floor muscles play a critical role in supporting the bladder, uterus, and rectum. During pregnancy, these muscles are under increased strain from hormonal changes and the weight of the growing baby.
When the pelvic floor is weakened or poorly coordinated, bladder control can be compromised, leading to urgency, frequency, or leakage.
Many pregnant individuals report needing to urinate frequently even when the bladder isn’t full. This could be due to increased sensitivity or decreased bladder capacity from external pressure. In other cases, pelvic floor tension or scar tissue from previous deliveries can restrict bladder function.
As a pelvic floor physical therapist, I often use techniques like bladder retraining, breath work, muscle coordination training, and gentle release work to help patients reduce urinary frequency and regain control over bladder habits.
What’s Normal…And What’s Not
Increased urinary frequency is one of the earliest signs of pregnancy and often persists throughout gestation. A 2021 systematic review in BMC Pregnancy and Childbirth found that up to 77% of pregnant women experience increased urination by the third trimester.
The causes are multifactorial, including:
Hormonal changes: Rising levels of human chorionic gonadotropin (hCG) and progesterone early in pregnancy promote blood flow to the pelvic region and kidneys, increasing urine production.
Increased blood volume: By the second trimester, a pregnant woman’s blood volume increases by up to 50%, causing the kidneys to filter more fluid.
Uterine pressure: As the uterus expands, it exerts increasing pressure on the bladder, especially in the first and third trimesters.
These changes are usually harmless and resolve postpartum.
When Is Increased Urination Not Normal?
While frequent urination is often benign, there are scenarios where it may signal an underlying issue. This includes the following:
Urinary Tract Infection (UTI)
Gestational Diabetes Mellitus (GDM)
Urinary Incontinence or Overactive Bladder (OAB)
Urinary Tract Infection (UTI)
UTIs are common in pregnancy due to hormonal and mechanical changes that slow urinary flow. According to a 2019 article in Obstetrics & Gynecology, 8–10% of pregnant women develop a UTI.
Symptoms to watch for include:
Burning or pain during urination
Urgency with little output
Cloudy or foul-smelling urine
Lower abdominal pain or fever
UTIs during pregnancy should be treated promptly to avoid complications like pyelonephritis or preterm labor.
Gestational Diabetes Mellitus (GDM)
Uncontrolled blood sugar levels can cause osmotic diuresis, leading to excessive urination. A 2020 study in the Journal of Maternal-Fetal & Neonatal Medicine noted increased urinary output as a subtle early symptom in some cases of GDM. If you're experiencing other signs like excessive thirst or fatigue, screening may be warranted.
Urinary Incontinence or Overactive Bladder (OAB)
Distinguishing between true urinary frequency and urinary urgency/incontinence is important. In a 2018 study published in International Urogynecology Journal, researchers found that up to 40% of pregnant women report symptoms consistent with OAB, which may worsen after delivery if left unmanaged.
Final Thoughts
Frequent urination is one of the earliest signs of pregnancy and often persists throughout, but persistent pain, urgency, or dysfunction are not normal and shouldn’t be ignored.
Understanding what’s happening physiologically can empower you to distinguish between common changes and concerning symptoms.
Your bladder is just one part of a complex and dynamic system during pregnancy.
If you’re unsure about what you’re experiencing, talk to your healthcare provider and don’t forget to consult a pelvic floor physical therapist who can assess the full picture.
Early intervention can go a long way in making your pregnancy more comfortable and setting you up for a smoother postpartum recovery.
Need help to prepare for an easier pregnancy and birthing experience?
If you’re looking for personalized, one-on-one sessions to address your pregnancy concerns, we provide pelvic health physical therapy services to women in the Jacksonville Beach area.
If you’re looking for providers who will listen to you and help you get to the root cause of your pregnancy concerns, we’ve got you. We’re here to help you if you’re experiencing pain, heaviness, leaking, or are pregnant/postpartum and want to continue safely working out/running/lifting during your pregnancy and get back to your sport after birth.
Get started today by booking a discovery call.
Resources:
Masoumi, Seyedeh Zahra, Fatemeh Simbar, and Zohreh Shahhosseini. "Prevalence and Risk Factors of Urinary Incontinence During Pregnancy: A Systematic Review and Meta-Analysis." BMC Pregnancy and Childbirth 21, no. 1 (2021): 343. https://doi.org/10.1186/s12884-021-03836-0.
Matuszkiewicz-Rowińska, Joanna, Teresa Małyszko, and Anna Wieliczko. "Urinary Tract Infections in Pregnancy: Old and New Unresolved Diagnostic and Therapeutic Problems." Archives of Medical Science 11, no. 1 (2015): 67–77. https://doi.org/10.5114/aoms.2013.39202.
Yogev, Yariv, and Moshe Hod. "Gestational Diabetes Mellitus: Diagnosis, Classification, and Management." Journal of Maternal-Fetal & Neonatal Medicine 33, no. 17 (2020): 3053–3059. https://doi.org/10.1080/14767058.2019.1576621.
Wesnes, Stian Langeland, Tone Hunskaar, and Kari Bo. "Urinary Incontinence and Weight Change during Pregnancy and Postpartum: A Cohort Study." International Urogynecology Journal 29, no. 3 (2018): 393–401. https://doi.org/10.1007/s00192-017-3417-6.
American College of Obstetricians and Gynecologists. Optimizing Postpartum Care: ACOG Committee Opinion Number 736. Washington, DC: ACOG, 2022. https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2022/07/optimizing-postpartum-care.