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Podcast: 女性备孕 (Female Fertility Planning), Episode 6 — “What Is Infertility”

Featured expert: Dr. Helena, Fertility Specialist, KL Fertility Centre

Source: DoctorSays360 podcast, Episode 6

Medically informed by a licensed fertility specialist; independently fact-checked against current reproductive medicine guidance and cited research. Not a substitute for individual medical advice.

 

A lot of couples get the timeline wrong in one direction or the other – either worrying after two or three months of trying, or waiting years past the point where a specialist could actually help. In this episode, Dr. Helena Lim Yun Hsuen (Dr. Helana Lim), a fertility specialist at KL Fertility Centre, lays out the clinical picture directly: what infertility technically means, when it is worth getting checked, what tends to cause it, and how much age really moves the odds.

What Doctors Actually Mean by “Infertility”

“Today, my topic is actually about infertility, or more importantly, more accurately, we should be calling it sub-fertility. Now, the definition of sub-fertility is the inability for a couple to conceive after trying for 12 months with regular sexual intercourse.” – Dr. Helena Lim

The 12-month mark isn’t an arbitrary cutoff – it is tied to how conception odds accumulate over time, as Dr. Helena Lim explains next:

“The reason why is because we know that about 84% of the couples would have conceived by the time they reach one year mark.” – Dr. Helena Lim

That statistic is also why the American Society for Reproductive Medicine (ASRM) and equivalent bodies elsewhere set evaluation thresholds at 12 months for women under 35 and 6 months for women 35 and up, the same split Dr. Helena Lim uses with her own patients.

When It’s Actually Time to See a Doctor

“If you and your partner have been trying for more than 12 months and still have not achieved a pregnancy, it is time for you to see a doctor to check what are the things that prohibits you from getting pregnant naturally. But it is also important to note the age of the female partner. Now, if your female partner’s age is more than the age of 35, then you should be seeing a doctor if you have not achieved a pregnancy by six months.” – Dr. Helena Lim

Under 35: 12 months of trying without success is the point to get checked.

While 35 and older, that window shortens to 6 months.

The shorter window for women 35+ isn’t an urgency for its own sake. It’s because, as Dr. Helena Lim explains later, egg quantity and quality start declining measurably around that age.

Where Sub-Fertility Actually Comes From

“Now, there are many causes for infertility. There are actually 30% is actually due to the female factors, 30% is due to male factors and about 30% is due to both female and male factors, and about 10% of sub-fertility is what we call unexplained sub-fertility.” – Dr. Helena Lim

In summary, Dr. Helena Lim splits the causes into four roughly equal groups: female-factor only, male-factor only, and combined female-and-male factors, each makes up about 30% of cases, with the remaining 10% unexplained even after testing. 

Add the male-only group to the combined group (30% + 30%), and a male factor is actually involved in about 60% of cases, six in ten. That’s the basis for testing both partners in a fertility work-up, not just the woman.

Why 35 Is the Number Everyone Quotes

“Now, if you ask me why the age of 35, it is important to note that medical statistics have shown that after the age of 35, the number of eggs that we produce in our ovaries, as well as the quality of eggs that we produce in our ovaries, actually reduces remarkably. So even if you try to get pregnant naturally or with a fertility treatment such as IVF, we know that your success rate actually starts to reduce gradually after the age of 35. But if you actually hit the age of 40, your chances of pregnancy, even with IVF, reduce remarkably.” – Dr. Helena Lim

“So we know that at the age of 40, your chances of pregnancy are actually about 40%. But by the time you reach the age of 45, your chance of pregnancy is almost zero. So therefore, even though IVF remains one of the most powerful tools we have to get you pregnant, we know that you will never ever be able to reduce or reverse the damage of ageing problem due to your ovaries and your fertility.” – Dr. Helena Lim

SART CORS data on IVF using a woman’s own eggs shows live birth rates in the 20-25% range around age 38-40, dropping into the single digits by the mid-40s – the same downward curve Dr. Helena Lim describes, just in more statistical language. The point she is making is one that IVF cannot get around: the treatment can help sperm and egg meet, but it cannot restore egg quality that has already declined with age.

The 25-35 “Window” and What Changes Outside It

“I would say that the best age for pregnancy would be between 25 to 35. Now we know that if you are actually pregnant before the age of 18 or below, we know that there is actually a higher risk of high blood pressure in pregnancy. The risk of having anemia in pregnancy is also higher. The risk of having an operative delivery, such as caesarean section is also higher.” – Dr. Helena Lim

“If you are actually over the age of 35, we know that your risk of having high blood pressure in pregnancy, diabetes in pregnancy, miscarriages and also fetal anomalies is also higher after the age of 35.” – Dr. Helena Lim

  • Under 18: higher rates of hypertensive disorders in pregnancy, anemia, and operative delivery.
  • Over 35: higher rates of hypertension, gestational diabetes, miscarriage, and fetal chromosomal or structural anomalies.

Both ends of that pattern show up consistently in the obstetric literature on adolescent and advanced-maternal-age pregnancies, which is part of why 25-35 gets described as the physiologically easiest window for pregnancy, not because pregnancy outside it is unsafe, but because the risk profile shifts in both directions.

It’s Not Just the Woman’s Age

“It is also important to note the age of the male partner as well, because we know that if your male partner’s age is advanced, it is associated with reduced sperm quality and quantity, and it is also increased risk of autism in the offspring if your male partner’s age is advanced.” – Dr. Helena Lim

This point gets left out of most fertility content aimed at couples, but it is backed by published research on paternal-age effects: advanced paternal age is associated with declining sperm parameters and a modestly elevated risk of certain neurodevelopmental conditions, including autism spectrum disorder, in offspring.

Key Takeaways

  • Subfertility is defined as 12 months of trying without success (6 months if the woman is 35+), not an immediate cause for alarm, but a clear signal to get evaluated.
  • Causes are split fairly evenly between female factors, male factors, and both partners together, so a full workup usually involves both people.
  • Egg quantity and quality decline measurably after 35 and more steeply after 40, which is why timing matters for anyone planning to use IVF or conceive naturally.
  • The lowest-risk pregnancy window is roughly 25–35; both very young and older maternal ages carry distinct, well-documented risks.
  • Male age affects sperm quality and is linked to a modestly higher neurodevelopmental risk in children; fertility planning isn’t only about the female partner.

About the Specialist

Dr Helena Lim Yun Hsuen

Dr Helena Lim qualified as a doctor from Universiti Kebangsaan Malaysia in 1999. She obtained her specialist degree in the UK in 2006 and completed her master’s degree in Obstetrics & Gynaecology in the same year. In 2018, Dr Helena Lim received her Fellowship award from the Royal College of Obstetricians & Gynaecologists, UK (FRCOG). Currently, she is one of the Senior Fertility Specialists at KL Fertility Centre.

Full profile & appointments: https://www.klfertility.com/dr-helena-lim-yun-hsuen/

Sources & Further Reading