Perimenopause and Pregnancy: Is It Possible?

Turning 40 – or even 45 – no longer means giving up the desire to become a mother. Increasingly, women are choosing to delay motherhood for personal or professional reasons and, when hormonal changes begin, one question frequently arises in consultations: Can I get pregnant during perimenopause?

In reality, perimenopause – more specifically, the premenopausal phase – is a transitional stage leading up to menopause. Changes in a woman’s body mean that fertility declines during this period; however, pregnancy is still possible, both naturally and through assisted reproductive treatments.

Pregnancy During Perimenopause is Possible

We know that pregnancy is no longer possible after menopause because the ovaries have ceased functioning and ovulation no longer occurs. However, during premenopause or perimenopause, the ovaries are still active. And where there is ovulation – even if unpredictable – there remains a possibility of pregnancy.

Although most women begin to notice the first changes of this stage around the age of 47 (approximately four years before menopause), it is considered normal for premenopause to begin between the ages of 40 and 45. If menstruation stops completely before the age of 40 (defined as 12 consecutive months without a period), this is referred to as premature menopause.

Therefore, we are typically looking at a transition period of around 4 to 8 years before reaching menopause. During this time, significant changes occur: menstrual cycles become irregular, ovulation becomes less predictable, and ovarian reserve gradually declines.

These disruptions do not mean that pregnancy is impossible during perimenopause. It is certainly more difficult, but as long as ovulation occurs, natural conception remains possible. So, if you are wondering, ‘Can I get pregnant during premenopause?’, the answer is yes – although the natural chances are significantly lower.

In fact, many women are surprised by an unexpected pregnancy during perimenopause when they believed it was no longer possible. For this reason, even at the age of 45 – when the probability of natural conception falls below 1–2% per cycle – specialists recommend continuing contraception until 12 consecutive months without a period have been confirmed, if pregnancy is not desired.

Your Fertility Changes During this Stage

Fertility declines with age, but it does not disappear suddenly. Instead, it undergoes a gradual and irregular decline due to key biological changes that occur during perimenopause and directly affect the likelihood of pregnancy:

1. Decline in ovarian reserve and egg quality

• Quantity: The number of eggs available in the ovaries gradually decreases.
• Quality: The remaining eggs are of lower quality and are more likely to have chromosomal abnormalities, making fertilisation more difficult and increasing the risk of miscarriage or genetic conditions.

2. Unpredictable ovulation

• Irregular cycles: Early in premenopause, cycles may become shorter; later on, they tend to become longer and more spaced out, as the ovaries produce fewer hormones.
• Anovulatory cycles: Many cycles occur without the release of an egg, even if menstrual bleeding is present.
• Erratic or unpredictable fertile window: As ovulation may occur earlier or later than expected, it becomes harder to identify the most fertile days.

3. Hormonal and uterine changes

• Hormones: Fluctuations in oestrogen and progesterone make it more difficult for the body to maintain an optimal environment for conception.
• Uterine receptivity: Hormonal changes may cause the endometrium (the uterine lining where the embryo implants) to become thinner, reducing the likelihood of successful implantation.

Confusion Between Pregnancy and Perimenopause Symptoms

It is very common to confuse the symptoms of pregnancy with those of perimenopause, as both share the same underlying cause: hormonal fluctuations that affect the menstrual cycle and mood. Here is a guide to help distinguish between them:

Shared symptoms

The confusion between perimenopause and pregnancy stems from the fact that there are common symptoms which can be attributed either to pregnancy during perimenopause or to the hormonal changes typical of this stage:

• Absence or irregular periods: This is the most misleading symptom. Towards the end of perimenopause, cycles become more spaced out, which may lead to the assumption that pregnancy is no longer possible. However, the absence of menstruation may, in fact, indicate pregnancy.
• Mood changes and fatigue: Both perimenopause and pregnancy can cause irritability, anxiety, and tiredness.
• Breast tenderness: Hormonal changes may lead to swollen or sore breasts in both cases.
• Abdominal bloating: Fluid retention and digestive changes are common in both.

Key differences to distinguish between pregnancy and perimenopause

Symptom	More likely in pregnancy	More likely in perimenopause
Nausea and vomiting	Very common (morning or evening sickness).	Very rare.
Body temperature	Generalized feeling of warmth.	Sudden hot flashes and night sweats.
Smell and taste	Hypersensitivity to smells and cravings/aversions.	Usually no changes in these senses.
Vaginal discharge	Usually increases (leukorrhea).	Tends toward vaginal Risks of late Pregnancy When discussing pregnancy during premenopause or after the age of 40, it is important to consider potential risks for both mother and baby due to biological ageing: Risks for the Mother Pregnancy complications: Higher likelihood of developing pre-eclampsia (high blood pressure) and gestational diabetes. Delivery: Increased rates of caesarean section, preterm birth, and postpartum haemorrhage. Risks for the Baby Genetic abnormalities: The risk of Down’s syndrome increases significantly (around 1 in 30 pregnancies at age 45, compared to 1 in 1,000 under age 30). Pregnancy loss: Higher risk of miscarriage or stillbirth due to reduced egg quality. Low birth weight: Greater likelihood of restricted foetal growth. The Importance of Contraception Contraception remains important during this stage because ovulation does not stop abruptly – it declines gradually. As long as you are still having periods, even if they are irregular or very light, there is a risk of an unplanned pregnancy with the associated risks mentioned above. Key Reasons not to Stop Using Contraception False assumptions: A delay of 3–4 months does not guarantee infertility; the ovaries may still release an egg unexpectedly. Dual benefit: Many hormonal methods (such as the mini-pill or intrauterine device) not only prevent pregnancy but also help relieve perimenopausal symptoms by regulating cycles and reducing hot flushes. Bone health: Some hormonal contraceptives help maintain bone mineral density, which begins to decline during this phase. When is it Safe to Stop? The standard medical recommendation is to wait until you have had 12 consecutive months without a period (confirmed menopause). Only at that point is the likelihood of pregnancy effectively zero. If you are using hormonal contraception, it can sometimes be difficult to determine whether menopause has been reached. In such cases, it is advisable to consult a gynaecologist to assess your situation and decide when to discontinue contraception. Confirming a Pregnancy If you suspect you may be pregnant – due to a delayed period or other symptoms – the first step is to take a pregnancy test (urine or blood). If the result is positive: It is important to consult a gynaecologist promptly. The gestational age should be assessed via ultrasound. Age-appropriate screening tests should be carried out. If, on the other hand, you have been trying to conceive during perimenopause without success, it is advisable to attend a specialised clinic for a comprehensive fertility assessment. Do you Want to Become a Mother During Perimenopause? Your desire to become a mother does not disappear simply because your cycles become irregular. If you are beginning to notice menstrual irregularities, unpredictable periods, or other symptoms of perimenopause – and you still wish to conceive – it is important not to delay. Fertility declines progressively at this stage, but real possibilities still exist with the right diagnosis and support. At Clínica Tambre, we carry out a personalised assessment of your ovarian reserve, hormonal profile, and reproductive situation in order to offer the most appropriate strategy – whether through in vitro fertilisation or other assisted reproductive techniques. When age and hormonal changes come into play, early evaluation can significantly improve your chances of achieving pregnancy. Modern reproductive medicine, as practised at Tambre, allows us to mitigate several of the biological risks associated with age, focusing primarily on genetic quality and the uterine environment. For this purpose, we may use Preimplantation Genetic Testing (PGT), ensuring that the transferred embryo has the correct number of chromosomes, thereby significantly reducing the risk of Down’s syndrome and other trisomies. We also optimise endometrial preparation to create the most receptive and stable environment for implantation. Finally, in cases where eggs are no longer viable, egg donation may be considered. If you would like to understand your real options for achieving pregnancy during premenopause, contact our clinics in Madrid or Alicante. At Clínica Tambre, we care for women’s reproductive health at every stage of life – and perimenopause is one of the most decisive. While it does not mark the end of fertility, it is a key moment to assess your situation and make informed decisions with the support of a specialised team. Frequently asked questions about perimenopause and fertility Can I get pregnant if I have irregular cycles? Yes, because irregularity does not mean a total absence of ovulation. The problem is that, since ovulation is unpredictable, it is difficult to identify fertile days. What are the chances of natural pregnancy after age 45? They are low (less than 1–2% per cycle), mainly due to the decrease in egg quality. Can the end of fertility be predicted? There is no single test that can predict with absolute certainty when your fertility will end or exactly when menopause will arrive. However, there are two main indicators of the state of your ovarian reserve: Anti-Müllerian hormone (AMH), which is the most common marker for estimating the quantity of remaining eggs (although it does not predict egg quality); and follicle-stimulating hormone (FSH), whose elevated levels indicate that the body is working harder to ovulate. Up to what age can assisted reproduction treatment be performed during perimenopause? Although there is no strict legal limit, most Spanish clinics, following ethical consensus, set the limit at 50 years of age. Is it possible to use my frozen eggs if I am already in perimenopause? Yes, as long as the eggs were vitrified at a younger age. The uterus usually does not “age” as quickly as the eggs, and it is possible to carry a pregnancy successfully. Back to list Older PGT-A in egg donation: when it can provide useful information before embryo transfer Sidebar Make an appointment Contact us