Progesterone is crucial in women of childbearing age. It is secreted by the ovary after ovulation naturally. The hormone is responsible for the slightly high body temperature during the second half of a female menstrual cycle. The hormone prepares the lining of the uterus in readiness for embryo implantation. If fertilization doesn’t occur, the lining of the uterus (endometrium) breaks down and monthly periods start. If a pregnancy occurs, progesterone is crucial to sustaining the pregnancy. Low progesterone hormone may be a cause of infertility in women. Additionally, women on fertility drugs can experience low levels of progesterone as a result of the medicines used to restore fertility. In such situations, a doctor may prescribe Endometrin. Many women on Endometrin have experienced a monthly period delay. Does Endometrin delays period, or other factors are to be blamed? Before answering the question, what is Endometrin and how does it work. 


What is Endometrin?


It is a drug which contains progesterone hormone. It supports embryo implantation and is used in assisted reproductive technology. The medication works by changing the uterus lining. The common dosage is 100 mg in form of a vaginal insert. It is inserted into the vagina three times once daily or as directed by the fertility specialist. Follow the directions of the doctor strictly; they (directions) may differ from the information in the patients' leaflet. It’s an easy procedure to insert the drug; you may request the nurse to guide you on the procedure. The good thing is that an applicator is available in the pack to aid in administering the tablet. The following are the main reasons Endometrin is prescribed:


  • To treat endometriosis –endometriosis is a painful condition and may cause heavy bleeding.
  • Treat certain types of breast cancer such as breast cancer and cancer of the uterus.
  • To regulate monthly periods.
  • To support a pregnancy, especially in the first trimester for women who are at risk of a miscarriage.
  • To prevent thickening of the uterus caused by estrogen in female around menopause on hormonal replacement therapy, also known as ovarian hormonal therapy. Estrogen is used during the therapy.


The physician may prescribe the medication for other reasons apart from those listed above, engage the medical care practitioner if unclear why you are on the drug. The medication is a prescription drug; don’t buy it without the direction of the doctor, it can lead to complications if taken without supervision.


You are now familiar with what Endometrin is and how it works. It is believed that Endometrin does delay periods. As earlier explained, the drug contains progesterone; the hormone is produced by the body naturally and is important for three main functions namely:


  • Thickening the lining of the uterus
  • Secreting a fluid to nourish the fertilized egg
  • Support embryo implantation


Think of this, the body still release progesterone hormone, although the levels might be low. On taking the Endometrin drug, it increases progesterone in the body. Therefore, with the rise of progesterone levels, the uterus lining becomes thicker. What does this imply? The uterus lining will need more time for the full breakdown. Bear in mind the uterus lining causes menstruation. With the extra time required, the periods are delayed for days or even weeks, depending on the dosage; the higher the dosage the more the periods would be delayed. Is Endometrin to be blamed for the delayed periods alone? Well, continue reading.


Other Causes for Delayed Periods


Period delays can occur as a result of other factors; there are countless reasons for this. The following are five main causes of period delay apart from Endometrin.


  • Pregnancy – if your monthly period delays, this is the first thing you think of. The idea of being pregnant to some is exciting, to others it is scary. If on Endometrin to help in conception, it’s advisable to see the doctor to carry out a pregnancy test to confirm if indeed pregnant or the periods are late.
  • Medications – any medicine you take affects how the body works or functions, even your reproductive system isn’t spared, thus drugs may delay period and Endometrin happen to fall under this category.
  • Stress - anything that puts mental pressure can delay menstruation, be it a new job, or any expected change can trigger a hormonal imbalance in the body, consequently pushing the periods off.
  • Weight – if one is extremely underweight, one doesn’t have adequate body fat for the menstrual periods to occur on a normal schedule. On the other hand, overweight females have a hormonal imbalance due to the extra weight as a result delayed or irregular periods.
  • Calculation – sometimes the explanation for late periods is the wrong calculation, most likely you timed wrongly, leading to a wrong conclusion that periods are late.


If the period is late, before concluding Endometrin has delayed the periods, rule out the wrong calculation, weight, stress and pregnancy.


Side Effects

Endometrin Progesterone 100 mg

Women not only worry about periods delay while on Endometrin but also on the side effects associated with the drug. The unwanted effects are innumerable, depending from one woman to another. It’s advisable to seek medical intervention if the side effects are bothersome, more so the common side effects. For the serious undesirable effect, consult the doctor with immediate effect. Below is a list of the expected unfavorable side effects:


  • Abdominal pains
  • Bloating
  • Breast tenderness
  • Constipation 
  • Cramps
  • Mood swings 
  • Nausea
  • Pain 
  • Vaginal discharge
  • Bleeding or spotting between periods
  • Urinary tract infection
  • Depression
  • Blood clot
  • Heart attack
  • Allergic reactions


As stated earlier, the side effects are numerous; you may refer to the fertility doctor for additional unwanted effects and the action to take in case they occur. Although the medication has helped many dealing with infertility and other health conditions, there is a category of women who should avoid using the medication because of existing medical conditions and other reasons for example:


  • Existing allergies - you may react to ingredients of Endometrin
  • Vaginal bleeding without any explanation
  • Breast cancer
  • Have problems with blood clotting, heart attacks, liver disease or stroke.
  • If on other vaginal products, because they may interfere with how the drug works and aggravate the side effects


In Conclusion


The above is an explanation why Endometrin does delay period; nonetheless, it’s not the only cause for delayed periods, as earlier mentioned.