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Irregular periods: causes and solutions to get pregnant
When Laura came to Vida Fertility, she had been trying to get pregnant for over a year. Her irregular periods were unpredictable: sometimes she would go 40 days without a period, sometimes she would bleed twice in the same month. She had tried everything: supplements, ovulation calculator apps, dietary changes… but nothing worked.
At Vida, we explained to her that her irregular menstrual cycle could be affecting her reproductive capacity.
After a series of female fertility tests, we designed a treatment adapted to her case. Today, Laura has a 1-year-old baby.
Like her, many women with irregular menstrual cycles have difficulty conceiving. Below, we talk to Dr. Marta Zermiani, fertility specialist at Vida Fertility about why irregular periods can affect fertility and what solutions exist to achieve pregnancy.
What are menstrual cycles?
It is important to differentiate between menstrual cycle and menstruation, as the menstrual cycle encompasses a series of hormonal and physical changes that occur in a woman’s body month by month.
The length of the cycle varies from woman to woman, usually between 23 and 35 days, although the average is 28 days. Its main function is to prepare the body for a possible pregnancy.
Understanding how the menstrual cycle works and recognising its variations is key to identifying fertile days and increasing the chances of conception.
How many days are considered irregular periods?
According to Dr. Marta Zermiani, fertility expert at Vida Fertility, ‘We consider a woman to have an irregular menstrual cycle when the time between one period and the next does not follow a pattern within the usual range of 21 to 35 days. In other words, if your period comes less than 21 days apart or is delayed beyond 35 days, it is an irregular period.
The duration of bleeding usually ranges from 3 to 8 days, but in women with irregular cycles, this time may not appear for long periods (amenorrhoea) or it may be significantly shortened or prolonged. In addition, it is common for bleeding to be heavier or heavier than usual, accompanied by more intense cramping.
In consultation, many patients say to me: ‘Dr. Marta, my period never comes when it should, some months it comes earlier and others it is late. Is this normal?’ The answer is that, although some variations are normal, when cycles are too unpredictable, they may be affecting your fertility and it is worth studying it in depth.’
Causes of irregular periods
The causes of irregular menstrual cycles can be related to
- Hormonal disturbances affecting the development of the menstrual cycle
- Polycystic ovary syndrome
- Gynaecological infections
- Perimenopause
There are also other situations that can cause temporary menstrual irregularities, such as recurrent miscarriages, breastfeeding or the postpartum period, where it takes time for the body to recover its normal hormonal rhythm.
Síntomas de un periodo menstrual irregular
If your menstrual cycle is unpredictable or significantly altered, it is essential to be aware of certain symptoms that may indicate the need for a medical consultation.
Some of the most common signs of irregular menstruation or periods are:
- Absence of menstruation for a prolonged period without being pregnant.
- Cycles that are too short, with periods occurring in less than 21 days.
- Excessive bleeding or, conversely, very scanty periods.
- Severe menstrual pain, which can affect your daily routine.
- Spotting or bleeding between cycles, outside of your expected period.
Although some variations may be common, when these symptoms recur or interfere with the search for pregnancy, it is essential to study their cause and evaluate possible treatments.
Is it possible to get pregnant with irregular periods? What is the probability?
According to Dr. Marta Zermiani: ‘Yes, but a more medical and personalised approach will be necessary’.
If you have extremely irregular cycles or no ovulation, pregnancy can be difficult without medical help. However, with a proper diagnosis and personalised treatment, it is possible to regain ovulation or resort to assisted reproductive techniques to achieve it.
At Vida Fertility, we analyse each case individually to offer the best strategy to help you achieve your dream of becoming a mother.
If you have been trying for more than 6 months without success, ask for a consultation with a fertility specialist.
How to get pregnant with irregular periods
If a woman has extremely irregular menstrual cycles, with periods exceeding 40-60 days or even with prolonged absence of menstruation (amenorrhoea), predicting ovulation becomes very difficult and, in many cases, the cycle may be anovulatory (i.e. no ovulation occurs).
Before considering treatment, it is essential to determine why the cycles are so irregular or non-existent. To do this, we carry out a complete fertility study that includes:
- Hormonal analysis (FSH, LH, estradiol, AMH, prolactin, thyroid hormones) to evaluate ovarian function.
- Transvaginal ultrasound to analyse ovarian reserve, rule out cysts or polycystic ovarian syndrome (PCOS).
- Ovulation monitoring by means of hormonal and ultrasound controls.
If we detect that there is no ovulation or that the cycle is highly unpredictable, specific treatment will be necessary.
Ovulation induction
If the problem is that ovulation does not occur regularly, ovulation induction can be used with drugs such as:
- Clomiphene citrate or letrozole
- Gonadotrophins
- Metformin
Cycle monitoring
In women with unpredictable cycles, the simple use of ovulation tests may not be sufficient, as in some cases the LH hormone may be elevated without actual ovulation. Therefore, more accurate monitoring is recommended:
- Monitoring ultrasound scans to confirm follicular growth and ovulation.
- Luteal phase progesterone analysis to verify that ovulation has indeed occurred.
Assisted reproduction treatments
When ovulation is not achieved with medication or there are other associated infertility factors, it is recommended to resort to treatments such as:
- Artificial insemination (AI): If there is an adequate ovulatory response, AI can be scheduled to increase the chances of fertilisation.
- In vitro fertilisation (IVF): If ovulation is not achieved naturally or there are other fertility problems (low ovarian reserve , male infertility problems, blocked tubes), IVF is the most effective option.
- Egg donation: In cases of premature ovarian failure or early menopause, egg donation allows pregnancy to be achieved with high success rates.
Frequently asked questions about irregular periods
How long can an irregular period last?
Dr. Marta Zermiani answers:
The length of an irregular period can vary significantly from one woman to another. While a normal menstrual cycle lasts between 21 and 35 days, in women with irregular periods this interval can be shorter or longer, with no predictable pattern.
Some women may experience prolonged periods of more than 7-8 days with heavy bleeding, while others may have extremely short and scanty menses.
If the irregularity continues for several months or interferes with quality of life, it is advisable to see a fertility specialist to identify the cause.
Is it normal to have irregular periods after a miscarriage?
Dr. Marta Zermiani answers:
Yes, it is completely normal for menstruation to take a long time to become regular after an abortion, whether spontaneous or induced. The first period usually reappears between 4 and 8 weeks later, depending on factors such as:
- How long the pregnancy lasted before the miscarriage.
- Whether a curettage or miscarriage was performed.
- The woman’s previous hormonal status.
- If there is any alteration in the endometrium after miscarriage.
The first few cycles may be irregular in duration and amount of bleeding, but with time they should stabilise. If after three months the cycles continue to be very inconsistent or menstruation does not reappear, it is advisable to have a gynaecological evaluation to rule out hormonal alterations or problems in the endometrium.
How to calculate my fertile days if I have irregular periods
Dr. Marta Zermiani answers:
If cycles do not follow a predictable pattern, identifying fertile days can be a challenge, but there are strategies to improve accuracy:
- Cervical mucus observation: During fertile days, vaginal mucus becomes clear, stretchy and egg-white-like.
- Ovulation test: Detects the LH hormone surge, which occurs 24-36 hours before ovulation. However, in women with very irregular cycles they can give confusing results.
- Medical monitoring: If you are seeking pregnancy, at fertility clinics we can do ultrasound monitoring and hormone tests to detect your ovulation more accurately.
If your cycles are excessively irregular (more than 40 days without a period or with differences of more than 10 days between cycles), it is advisable to see a specialist to assess whether there is an ovulatory dysfunction that needs to be treated.
What happens if I have a menstrual period every other month?
Dr. Marta Zermiani answers:
When menstruation appears intermittently, it is possible that there is an ovulatory dysfunction. This means that some months the ovaries do not release an egg (anovulation), which prevents menstruation.
The most frequent causes of this disorder include:
- Polycystic Ovary Syndrome (PCOS): Many women with PCOS ovulate irregularly or not at all in certain months.
- Thyroid disorders: Both hypothyroidism and hyperthyroidism can affect the regularity of the menstrual cycle.
- Low ovarian reserve: In women over the age of 35, a decrease in the number of eggs can cause ovulation to become less frequent.
- Stress and changes in body weight: Sudden weight loss or gain, as well as prolonged stressful situations, can inhibit ovulation.
If your period comes every other month, it is advisable to have a gynaecological and endocrine evaluation to determine the cause and evaluate possible treatments to regulate the cycle, especially if you are looking for pregnancy.
How long is the menstrual cycle in women with irregular periods?
Dr Marta Zermiani answers:
In women with irregular periods, the menstrual cycle can vary significantly. While a regular cycle typically lasts between 21 and 35 days, an irregular cycle may be shorter, longer, or completely unpredictable.
If you’re experiencing irregular menstruation and trying to get pregnant, it’s important to understand your cycle patterns and consult a fertility specialist. Irregular cycles may indicate underlying hormonal imbalances or ovulatory issues that could make it more difficult to conceive without support.
Irregular periods at 40: what’s happening?
Dr Marta Zermiani explains:
Irregular periods in your 40s are common and often linked to perimenopause, the transition phase before menopause. During this time, hormonal fluctuations can cause changes in cycle length, bleeding intensity and frequency.
However, if you’re trying to get pregnant at 40 and notice your period becoming irregular, it’s essential to act quickly. Both egg quality and ovarian reserve decline sharply after 40, and cycle irregularity can be a sign of reduced ovarian function. In many cases, women in their 40s may benefit from advanced fertility treatments such as IVF with donor eggs, which significantly increases the chances of a healthy pregnancy.
If you have irregular periods and want to get pregnant, speak to a fertility specialist as soon as possible. A proper diagnosis and personalised treatment plan can make all the difference.
