Signs of Pregnancy When Taking Oral Contraceptives

Julie Kirk
Contributor: Rachel Hanson
woman looking at pregnancy test

Oral birth control is highly effective in preventing pregnancy when taken correctly. However, even though the pill is about 99% effective, there is a very small percentage of women who will still get pregnant while on the pill.

Signs of Pregnancy While On the Pill

If by chance you have become pregnant while on the birth control pill, it may be initially difficult to determine definitively by the signs alone.

Similar Hormonal Symptoms

Early symptoms of pregnancy can be very similar to the side effects of the birth control pill. The similar symptoms of both pregnancy and birth control side effects you may experience include:

  • Nausea
  • Headaches
  • Breast tenderness
  • Spotting
  • Fatigue
  • Missed period (depending on the type of birth control pill you're on)
  • Mood swings
  • Weight gain
  • Acne
  • Frequent urination
  • Constipation or diarrhea
  • Stomach upset

Most of these symptoms can be attributed to hormonal changes related to pregnancy or to the pill which is why they are so similar. Therefore, it will be difficult to determine if you are pregnant by symptoms alone.

Spotting Compared to Light Periods

Spotting may occur when you first start using the pill. However, it is also common to experience spotting during early pregnancy. If a woman typically has lighter cycles, it may also be possible for her to mistake the spotting for a period.

Taking a Pregnancy Test Is Best

If you're worried that you may be pregnant while on the birth control pill, you should take a home pregnancy test and make an appointment with your OB/GYN doctor to discuss your concerns.

Additional Things to Know About Birth Control Pills

The side effects of birth control pills may differ depending on the pill you're prescribed.

Different Pills Have Different Effects

The type of hormones and the dose of hormones in the various pills, like Yaz or Loestrin, may cause different or possibly stronger side effects. This can vary from woman to woman. Some women will have no problem at all with side effects from the birth control pill, others may have just minimal side effects while others experience extreme side effects.

Side Effects and Adjustment Period

It is not unusual to experience these side effects when you initially start your birth control prescription. Typically, it takes about 2 to 3 months for your body to adjust to the hormones and the side effects should go away. However, if they do not go away after 3 months then you may need to stop the pill altogether and try a different type or brand of the many birth control pills available or possibly another form of birth control.

Discontinuing Birth Control Pills

There is a chance that you may not realize that you are pregnant and continue to take your birth control pills. This is especially true if you are using a continuous, extended-cycle type of birth control pill which would cause you not to have a period for months at a time. Under these circumstances, it would be difficult to determine if you missed a period, therefore, not recognizing one of first and most common pregnancy symptoms. Once you confirm that you are pregnant, you should discontinue the use of your birth control pills.

Can Taking the Birth Control Pill Harm the Baby?

It is imperative that you discontinue the use of the birth control pill once you learn that you're pregnant. However, there is actually very little evidence that unknowingly continuing birth control during pregnancy has a negative impact on the baby. There also appears to be no correlation between taking birth control pills during early pregnancy and an increased risk of birth defects.

Your Doctor Is Your Best Resource

If you are pregnant or think you are pregnant despite your use of oral contraceptives, visit your doctor as soon as possible. Don't ignore your symptoms or concerns. It is important to talk to your doctor especially if you find yourself in the position of an unplanned pregnancy. He will help inform and guide you while discussing your options. While this can be a difficult and stressful situation to find yourself in, be reassured that your doctor will provide the support and medical care that you need at this time.

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Signs of Pregnancy When Taking Oral Contraceptives