Natural periods and periods while on hormonal birth control are not the same. In fact, a period on hormonal birth control (HBC) is not a period at all and has several differences.
Often the pill is described as something used to regulate your period, and while on the pill, your cycle can appear completely regular and last the same amount of time every month. However, in reality, that period you may experience while on the pill is not actually a period at all, but something called a breakthrough bleed. To understand this, it is helpful to understand how HBC affects your body.
Your Body on Hormonal Birth Control
HBC shuts down your natural hormonal system. The pill has synthetic estrogen and progestin and these hormones inhibit your natural hormones to create a cycle completely dependent on the pill. HBC works to prevent pregnancy by stopping natural ovulation and facilitating an environment in the vagina that is not conducive to sperm health. When you stop taking the pill on the days indicated by the directions, it causes a breakthrough bleed, i.e. bleeding caused by hormonal withdrawal. When you stop taking the synthetic hormones, your body will have a sudden drop in hormone level, which then causes the lining of the uterus to shed. This may resemble a normal period in some people; in others the period may be very light or uncomfortably heavy. Some people may only spot or not bleed at all.
The Myth of Period Regulation
Hormonal birth control is often touted as a method to regulate a period or cycle. However, it actually does nothing of the sort. It essentially creates a fake cycle that only lasts as long as you are on the pill. This can temporarily ease the discomfort of those who have polycystic ovary syndrome (PCOS) by causing the uterine lining to shed every month. It may also return a “period” to those who haven’t had one in awhile. Additionally, it can stop excessive hormone production that results in very heavy periods or endometriosis. Once you stop taking the pill, these benefits go away. The problem with using the pill to treat these issues is that it ultimately only treats the symptoms and not the underlying problem. For people who are hoping to conceive, HBC will not correct these problems and they will reappear when the pill is stopped.
What Happens In a Natural Period?
In a normal cycle, your body’s hormones fluctuate as it prepares for an egg for release, followed by your uterus is preparing for a fertilized egg. In a natural cycle, your uterine lining thickens in preparation for the fertilized egg. When this doesn’t happen, it naturally sheds in a period at the end of the cycle. In some people, unbalanced hormones may cause the uterine lining to get thicker than it should, which can cause very heavy periods. With HBC, your lining doesn’t thicken at all and you do not ovulate. This is one of the reasons why you may experience very little bleeding while on the pill.
Breakthrough and Unexpected Bleeding
Another fairly common occurrence of HBC is breakthrough bleeding or spotting outside of the normal period time. It happens to as many as one in five people who first start taking the pill. It may stop after a few months or you may need to switch to a different pill or hormone level.
The main concern with taking HBC for a long period of time is that the consistent dose of synthetic hormones may completely shut down your body’s ability to make natural hormones. This can lead to difficulties with conception and other specific health problems normally regulated by natural hormones such as blood clotting, cancer, bone density loss and more. It is especially detrimental to teens whose bodies have not formed a regular cycle yet.