Understanding the Causes and Effects of Late Periods on Birth Control Pills

May 18, 2023
Tripti Mohan – May 18, 2023
Understanding The Causes and Effects of Late Periods on Birth Control Pills

The idea of taking birth control pills is not to get pregnant. But you might…

The idea of taking birth control pills is not to get pregnant. But you might miss your periods or get late periods when on birth control. Does that get you nervous and confused? In this article, we will tell you what causes these missed/late periods and how they can affect you. But first, – how late can a period be on birth control? what is a birth control pill, and how does it work?

How to Prevent Pregnancy?

In simple terms, these are oral contraceptives used to prevent pregnancy. There are several types of birth control. The most common ones act on your hormones so that you don’t ovulate and hence, don’t conceive. Most of these contain both estrogen and progesterone, while some contain only progesterone. They play games with your natural menstrual cycle so that you do not produce any eggs for fertilization. To learn how this works, read on.

How Birth Control Pills Affect Menstrual Cycle

Birth control pills come in different combinations, those with estrogen and progesterone or only with progesterone (known as mini-pills). Usually, there are 21 active pills and 7 placebo pills. The placebo pills are inactive and meant to be taken every day at the required time without fail to keep you on track. These 7 days when you are not taking active birth control are referred to as the rest week when you can expect your periods. What happens here is that the uterine lining is made very thin. During the placebo days, this lining is shed, leading to a light period.

How Birth Control Pills Affect Menstrual Cycle different phases

The interesting fact here is that this period is also not your regular period. It is called “withdrawal bleeding,” which simply means that your body is reacting to not receiving the normal hormones. If you continue to take active pills during these 7 days, you can skip your periods altogether.

Side Effects of Birth Control Pills

  • Changes in the menstrual cycle
    • Bleeding during the active period is known as the breakthrough period or spotting
    • Missed or late period
  • Tender or sore breasts
  • Headaches
  • Nausea
  • Weight gain.
  • Vaginal discharge
  • Decreased sex drive

Note that not everyone experiences all of these or any of these side effects. Some rare, yet serious side effects that can cause risk to pregnancy and health are given below.

  • Blood clots in the heart, lungs, eyes, brain, legs, etc
  • Liver tumor
  • High blood pressure
  • Risk of breast and/or cervical cancer

Reasons for a Late Period on Birth Control Pills

Normally, there could be several reasons for late periods such as diet change, stress, high-intensity workout, and hormonal imbalance caused by thyroid or PCOS. If taken religiously every day at around the same time, birth control pills can be 99% effective. In 2-3 months, your menstrual cycle can also be regulated so that you get your periods during the placebo week. In this case, you need not think of pregnancy if you miss a period or if there is a delay.

Reason for a later period by use of birth control pills

However, if you have skipped the dosage or even taken it at a different time, then you must check if you are pregnant.
So, if your period is over 90 days late, it could be because you are breastfeeding, pregnant, or facing menopause. It may also occur if you have changed your birth control method from pills to EluRyng.

When to Seek Medical Attention

Stress could be why you missed your period. If not, you could be pregnant, using hormonal birth control, breastfeeding, or experiencing menopause. In case none of these reasons align, you may need to seek medical help. If you are facing some of the following problems along with late periods while using progestin birth control pills, meet your doctor.

when to seek medical attentions for later periods
Abdomen pain and vomiting
Depression and mood swings
Excessive growth of body hair
Blurred vision
Difficulty in balance and coordination

Your healthcare provider will most likely ask you about your existing pill and discuss the possibility of changing it from one type to another. They may also probably advise you to try any other type of contraceptive. These decisions are made based on changes in your weight, blood pressure, vision, and other external symptoms.

Preventing Late Periods on Birth Control Pills

On your part, there are a few steps you can take to prevent late periods on birth control pills.

preventing late periods on birth controll pills

Some of these are listed here:

  • Always follow the usage instructions provided by your doctor. The format could be different from your friend’s, depending on each of your menstrual cycles. So listen to your doctor.
  • Follow a routine. The pill should be taken every day at the same time. A change in this timing can also upset your cycle.
  • Keeping a reminder on your phone is a good idea.
  • Track your periods using a calendar so that you don’t miss the dates. Even more convenient is to use menstrual tracker apps.
  • If you miss a pill due to vomiting soon after consuming it or forgetting to take it on time, you may need to take it again immediately.
  • Don’t wait for one pack of pills to finish to buy another set. Always be ready with your next set of pills.


Getting a late period on birth control pills is not an uncommon event. There could be several reasons why you missed or got a delayed period. Being aware of the possibilities is your way of keeping ahead of the situation.

Do you always take your pills religiously without missing any? Then you need not worry.99% chance is that you are not pregnant if that is what is on your mind. We hope this article has answered all your questions in this regard. Do not hesitate to approach your doctor and clear your mind of doubts about your menstrual cycle and birth control pills.

  • https://www.sciencedirect.com/science/article/abs/pii/
  • https://youngwomenshealth.org/askus/bcp-placebo-pills/

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