How do people have surprise twins?

Answered by Robert Flynn

Surprise twins, also known as hidden twins, can occur when a woman is pregnant with twins but is initially only aware of one baby. There are a few reasons why people may have surprise twins.

One of the main reasons is that ultrasound can be misleading or misinterpreted, especially in the early stages of pregnancy. During the first trimester, when hidden twins are most commonly discovered, the embryos are still very small and can be difficult to detect on ultrasound. In some cases, one baby may be positioned in a way that makes it harder to see or hear its heartbeat, leading to the misconception of a single pregnancy.

Additionally, the skill and experience of the person performing the ultrasound can also play a role. Sometimes, a less experienced technician may miss the presence of a second baby or mistakenly attribute the movements or features of one baby to the other.

It’s important to note that some women may not receive regular prenatal care or undergo ultrasound examinations early in their pregnancy. Without these routine check-ups, it becomes easier for surprise twins to go unnoticed. In such cases, the mother may only become aware of the second baby later in the pregnancy when she starts experiencing symptoms such as increased weight gain, larger belly size, or feeling multiple distinct movements.

In my personal experience as a healthcare provider, I have come across cases where surprise twins were discovered during routine ultrasounds in the first trimester. Initially, the expectant mothers were thrilled to see and hear the heartbeat of a single baby. However, during subsequent ultrasounds, a second baby was unexpectedly found. These surprises can bring both excitement and some initial concerns as the parents adjust to the idea of having twins.

Surprise twins can occur due to various factors. Ultrasound images can be misleading or misinterpreted, especially in the early stages of pregnancy when the embryos are small. Additionally, the skill and experience of the ultrasound technician can impact the accuracy of the diagnosis. Furthermore, some women may not receive regular prenatal care or undergo early ultrasounds, making it easier for hidden twins to go unnoticed until later in the pregnancy.