Updated by the Progyny Clinical Team — June 2025.
If you’re not in fertility treatment, you may not know what a “chemical” or “clinical” pregnancy means.
A chemical pregnancy is a very early miscarriage that happens before the fifth week of pregnancy. It usually happens around the time of your expected period, so you may not even know you were pregnant.
After an egg is fertilized, your body starts to make a hormone called human chorionic gonadotropin (hCG). This hormone is tested by urine and blood pregnancy tests and is often the first and earliest evidence of a pregnancy. Pregnancy tests become positive at much lower levels of hCG than when a pregnancy can be identified on ultrasound.
In a chemical pregnancy, there’s enough hCG to get a positive test, but the pregnancy stops growing before anything can be seen on an ultrasound. The test may turn negative a few days or weeks later.
What’s the difference between a chemical and clinical pregnancy?
A chemical pregnancy happens too early to see anything on an ultrasound. A clinical pregnancy is one that shows up on an ultrasound, usually seen as early as five to six weeks gestational age.
What conditions may cause a chemical pregnancy?
There are different reasons that a chemical pregnancy may occur. Sometimes, the embryo has genetic problems that stop it from growing. This can happen at any age but is more common in people in their late 30s or older. Other times, problems with the uterus, like fibroids or polyps, can make it harder for the embryo to attach and grow. In many cases, the cause is unknown.
Conditions that may be related to an early miscarriage and lead to chemical pregnancy include:
- Uterine fibroids
- Congenital uterine malformations such as uterine septum
- Sperm issues
- Endometrial polyps
- Hormonal abnormalities which create luteal phase defects
- Genetic/chromosomal abnormalities
- Underlying medical conditions such as thyroid disease, diabetes, or clotting disorders
What role does sperm play in a chemical pregnancy?
Sperm is needed to fertilize an egg, which is the first step in forming an embryo. If everything goes well, the embryo may implant in the uterus and begin to grow. But sometimes, a pregnancy doesn’t progress successfully.
A low sperm count, poor movement, or irregular shape can make it harder to fertilize an egg or support a healthy pregnancy. Known as “male factor infertility,” it’s one of many reasons a chemical pregnancy occurs.
How does a chemical pregnancy affect future pregnancies?
A chemical pregnancy from unassisted conception means that fertilization happened and the embryo started to implant in the uterus. In fertility treatments, fertilization occurs in a lab and is transferred to the uterus. A chemical pregnancy in both cases suggests early embryo attachment. And if you’ve had more than one loss, schedule a visit to talk about it with your provider.
In the absence of an underlying cause, the likelihood of success in future pregnancy is reassuring. However, the chance of getting pregnant is lower for older couples.
Summary
Chemical pregnancies are early losses that happen before a pregnancy can be seen on an ultrasound. They’re common, but if it happens more than once, talk to your provider about testing for possible treatable causes like hormonal, structural, or genetic factors.
If you have questions or concerns, Progyny is here for you. Please contact your Progyny Care Advocate for support.
Disclaimer: The information provided by Progyny is for educational purposes only and is not medical advice. Always consult a qualified healthcare provider for medical guidance.