What are the risks of pregnancy if I took my progesterone-only pill at 5:40 CET and 20:15 GMT, having had sex 2 days prior?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 28, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

The risk of pregnancy in your situation is increased due to the delayed timing of your second pill, and it is recommended that you take your next pill at your regular time and consider using a backup contraception method like condoms for the next 48 hours. Progesterone-only pills (POPs) should ideally be taken at the same time each day, with a window of only 3 hours for most brands, as stated in the CDC recommendations for contraception use 1. Your pills were taken approximately 18 hours and 35 minutes apart (accounting for the time zone difference between Amsterdam and UK), which exceeds the recommended window. This delay could potentially reduce the contraceptive effectiveness. If you had sex two days ago, sperm could still be viable in your reproductive tract, though the risk decreases with each passing day. According to the CDC guidelines, if a progestin-only pill is taken more than 3 hours past the recommended dose, a backup method should be used for 2 consecutive days 1. To minimize pregnancy risk, consider using a backup contraception method like condoms for the next 48 hours. If you're concerned, emergency contraception might be an option if taken soon, though its effectiveness decreases with time. POPs work primarily by thickening cervical mucus and thinning the uterine lining, with some types also inhibiting ovulation. Consistent timing is crucial for maintaining these effects, as hormone levels can drop when doses are delayed. Key points to consider include:

  • The importance of taking POPs at the same time each day
  • The need for a backup method if a dose is delayed by more than 3 hours
  • The potential for reduced contraceptive effectiveness with delayed doses
  • The option for emergency contraception if taken soon after unprotected intercourse.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Timing of Progesterone-Only Contraceptive Pill Ingestion

  • The user took their progesterone-only contraceptive pill at 5:40 in Amsterdam time yesterday and 20:15 in UK time today, which is approximately 14 hours and 35 minutes apart, considering the 1-hour time difference between Amsterdam and the UK.
  • According to the study 2, clinical guidelines for progestin-only pills state that each pill should be taken at the same time each day, with only a "three-hour window" of tolerance before back-up contraception should be used.

Risk of Pregnancy

  • The user last had sex two days ago, which is within the time frame where emergency contraception can be effective 3, 4, 5, 6.
  • However, the provided studies do not directly address the specific situation of taking a progesterone-only contraceptive pill at different times in different time zones.
  • The study 4 mentions that levonorgestrel, a progesterone-only emergency contraceptive, is approved for use up to 72 hours after unprotected intercourse, but it does not provide information on the timing of ingestion in relation to the user's menstrual cycle or the effectiveness of the contraceptive pill when taken at different times.

Emergency Contraception Options

  • If the user is concerned about the risk of pregnancy, they may consider using emergency contraception, such as ulipristal acetate or levonorgestrel, which can be effective up to 5 days after unprotected intercourse 4, 5, 6.
  • The study 3 mentions that combination estrogen-progestin birth control pills can be used as emergency contraception, but this may not be relevant to the user's situation since they are taking a progesterone-only contraceptive pill.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Emergency contraception.

Archives of family medicine, 2000

Research

Update on emergency contraception.

Advances in therapy, 2011

Research

Practice Bulletin No. 152: Emergency Contraception.

Obstetrics and gynecology, 2015

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.