Q: Hey Doc! What is the meaning of that black line under the belly button and on top just a little?

A: Hello dear, thanks for writing in.

What you’re noticing is most likely related to something called the linea alba and linea nigra.

Let me explain.

First, linea alba. This is a natural line that runs vertically down the middle of the abdomen, from the chest area down to the lower tummy. Everyone has it, but in many people it’s very faint and barely visible.

Then, linea nigra. When the linea alba becomes darker or more visible, it is called linea nigra. This darkening happens due to hormonal changes, especially increased estrogen and progesterone.

Therefore, it is very common in:

Important things to know

Linea nigra is not dangerous

It is not a disease

It does not mean something is wrong with your womb

It does not automatically mean pregnancy

It is simply increased skin pigmentation triggered by hormones.

Will it go away? In many women, the line fades gradually over time once hormones stabilize. In some, it may remain faintly visible and that is completely normal.

Please see your doctor is if the dark line is accompanied by:

Missed periods

Breast tenderness

Nausea

Lower abdominal pain

Then a pregnancy test or medical review is advised not because the line itself is dangerous, but to understand what’s driving the hormonal change.

I hope this helps!