What is a Chemical Pregnancy?

Until about 40 years ago, the concept of a chemical pregnancy was virtually unknown. This is not because such pregnancies didn’t occur, but because we simply lacked the tools to detect them.  

A chemical pregnancy can be defined as a pregnancy that is only diagnosed by chemical means  —most commonly, means by a pregnancy test. At this extremely early stage, the pregnancy develops long before anything can be seen through an ultrasound. 

Before advancements in reproductive medicine, these early losses went largely unnoticed. The only subtle indication that a chemical pregnancy may have occurred was maybe through an irregular or delayed menstrual cycle. Occasionally, women would notice that their period arrived a few days late and wonder if they might have briefly been pregnant for a short time, but there was no way to confirm it. 

Today, with advanced testing, we now understand that chemical pregnancies are not only happening but also that they happen quite frequently. In fact, research suggests that one-third of all implantations end up as a chemical pregnancy. This statistic highlights just how frequently early pregnancy loss can occur, often without individuals even realizing it. 

An important point to understand is that a chemical pregnancy can only happen if implantation has already taken place. That embryo that implants needs a good number of days to get to the point where it makes contact with a maternal vascular system. This process can take almost two weeks.  

Therefore, if a chemical pregnancy is diagnosed, implantation did occur. And if that implanted pregnancy is lost, it is medically considered a miscarriage. In other words, a chemical pregnancy is simply a very early miscarriage. 

If you’d like to learn more, you can watch Dr. Gleicher explain chemical pregnancies in greater detail below or visit our YouTube channel.