Ways to boost fertility: How to increase your chances of getting pregnant

If you’ve ever looked into how to increase your fertility or how to increase your chances of getting pregnant, you’ve probably realised that there can be a myriad of factors that can influence a person’s ability to conceive. Certain conditions, such as endometriosis and polycystic ovary syndrome (PCOS) in women, and testicular cancer or infection in men, can impact fertility. However, here, we’ll concentrate on the nutrition and lifestyle elements that are worth being aware of for both sexes as you embark on your journey.

Aim for a healthy weight

Obesity is likely to induce resistance to the hormone, insulin, and Hyperinsulinemia (where the amount of insulin in the blood is higher than what’s considered healthy). In response to insulin resistance, your pancreas increases secretion of this hormone to compensate. In turn this higher insulin level leads to the reduction of something called sex hormone-binding globulin and hyperandrogenaemia (an excess amount of the group of sex hormones known as androgens in the body). It can also lead to disruption of a hormone called IGF (insulin-like growth-factor) affecting how it works.

♀ The result is increased chances of menstrual and ovulatory disturbance in obese women. Fortunately, it’s been shown, when women are able to lose weight, this is associated with a reduction in insulin resistance and a return to effective ovulation.

♀ For women, especially those with PCOS, even losing 2-5% of total body weight improves ovulation and is more likely to lead to spontaneous pregnancy, plus improved outcomes for ovulatory cycles and pregnancy in women can be seen if 5 and 10% of body weight is lost.

♂ For would-be fathers, insulin resistance can lead to a reduction in semen volume (number of millilitres per ejaculation), sperm counts (number of sperm per millilitre) and motility (the ability to move independently), plus abnormal sperm morphology (size, shape, structure and form).

♂ The good news is that weight loss in men may potentially lead to better sperm quality as one cohort pilot study of 43 men concluded.

If this is relevant for you, our article on ways to reduce body fat may help.

Support your metabolic health

♀ Somewhat related to the above, women experiencing fertility issues can have underlying metabolic disorders. Indeed, there’s a two-way link between metabolic and reproductive health, with the former being important for successful conception. The combination of obesity, insulin resistance, high blood pressure and an imbalance in lipids (fatty compounds like the different types of cholesterol) is known as metabolic syndrome. This condition can significantly disrupt your hormone system. One of the knock on affects is on ovulation; women with metabolic syndrome may have an unsettled menstrual cycle because of higher levels of androgenic male sex hormones.

♀ Polycystic ovaries can also be an indication that your metabolic health could be out of balance. Hyperandrogenism (excess levels of male sex hormones) in the blood and hyperandrogenic features, such as facial hair growth form some of the diagnostic criteria for the condition. PCOS can make getting pregnant harder due to irregular or no ovulation.

♂ Meanwhile, erectile dysfunction in men can be a sign that your metabolic health could be out of balance. In fact, diabetes-induced high blood sugar (hyperglycaemia) can negatively effect sperm quality. Men with metabolic syndrome may also have lower testosterone levels than those who aren’t overweight, plus there’s an association between the condition and premature ejaculation.

Below are some of the ways you can support your metabolic health. You can also read more in our article here.

Test your vitamin D levels and supplement

♀ If you’re a woman reading this, did you know you have vitamin D receptors (VDRs) in your ovaries, placenta, myometrium (middle layer or your uterus wall) and endometrium (the lining you shed during your period)? VDRs prompt cell-signalling to maintain healthy calcium levels, which, in turn, regulate many biological functions. As such, there’s growing evidence that indicates the pro-hormone vitamin D is important to fertility, with a meta analysis concluding that sufficient serum vitamin D levels are linked with more positive pregnancy tests, clinical pregnancies and live births in women using artificial reproductive technology.

♂ Should you be a man reading this, you may be interested to know that VDRs are located in your sperm and testicles. Having both a too low (less than 20 ng/ml) or high (more than 50 ng/ml) concentration of vitamin D in serum adversely affected sperm count, movement and morphology.

♂ A small randomised study of 86 infertile men with vitamin D3 deficiency found that supplementation of vitamin D over three months improved sperm motility, but semen volume, sperm count and morphology weren’t significantly impacted. However, the study was limited, in that the sample size was small and all the participants were from an infertility clinic in Iran, so the results may not be generalisable.

♀ ♂ Regardless, to compensate for food sources not being sufficient and a lack of sunlight, in the UK, from the beginning of October until the end of March, it’s necessary for most people, men and women, to take supplements. Taking a vitamin D test will give you an idea of how much you need.

Lose the booze

Alcohol can use up many of the essential nutrients your body needs, such as zinc, iron, vitamin B, calcium, along with others like magnesium (found in dark green leafy vegetables, nuts, seeds and wholegrains), sodium (present in good quality sea salt) and potassium (sources include avocados, spinach and sweet potatoes), which are all needed for reproduction (amongst many other things!). Moreover, chronic alcohol intake can change how effectively macronutrients and micronutrients are absorbed in your small intestine.

♂ It’s also responsible for altering hormone activity, particularly in men. Alcohol seemingly:

• disrupts the production of the reproductive hormones:
  • GnRH (Gonadotropin-releasing hormone),
  • FSH (Follicle-stimulating hormone),
  • LH (Luteinizing hormone),
  • and testosterone.

• and hampers the way the Leydig cell (the main source of testosterone in men) and Sertoli cells (that provide physical, nutritional and regulatory support for developing germ cells that evolve into sperm) and work.

The result is the potential impairment of spermatozoa (sperm capable of moving) developing.

♂ For men, chronic alcohol consumption has been linked with negative outcomes, including shrinking testicles (known as testicular atrophy, which, if diagnosed early enough, may be reversible), lower sex drive and depleted sperm count. By chronic alcohol consumption we’re talking about drinking at least 180ml/18 units of alcohol daily (brandy and whisky, both 40%-50% alcohol content) for a minimum of five days per week. A meta analysis of 57 studies with 29,914 participants from 26 countries/regions also found alcohol is a risk factor for reduced sperm volume.

♀ In women, high alcohol consumption (more than 140g/17.5 units a week) was associated with an elevated risk of having infertility examinations at hospital in a study of 7,393 women. Another study of 155 women found those who experienced more hangovers during the previous year were more likely to be infertile, indicating that the amount of alcohol drank matters.

But how much alcohol is too much in terms of fertility?

♀ The answer remains unclear, however, women in an assessment of 1,924 couples, who exceeded seven units of alcohol per week, had a considerably longer time to pregnancy (the number of menstrual cycles needed to conceive) than those who drank one-seven units each week. Additionally, there was over 50% less of a chance of conception during a menstrual cycle when female participants in another older study had drank alcohol compared to those who did not.

So, perhaps considering cutting out alcohol altogether when trying to conceive is the way to go. At the very least, the British Fertility Society advises having no more than 1-2 units of alcohol per week if you’re a woman trying to get pregnant and don’t exceed 4 units per week if you’re a man trying for a baby.

Control your caffeine

♀ For women trying to conceive, caffeine should be limited, perhaps to 1-2 coffees as day, according to the British Fertility Society. A 2018 review of evidence on caffeines effects on fertility remained inconclusive but more recent research in 2021 suggested that a high intake of caffeine (more than five cups or 500mg per day) may delay pregnancy as the stimulant can interfere with egg fertilisation and the implantation process.

♂ For men, the way in which caffeine impairs fertility, or if it does at all, isn’t well understood, but it may adversely impact fertility via sperm DNA damage, as one systematic review of 28 research papers involving 19,967 men suggested. However, evidence from the review that caffeine was a culprit for low quality sperm and fertility was inconsistent and inconclusive.

♀ ♂ Another 2020 systematic review and meta analysis conducted on four studies of 12,912 participants (this time prospective studies involving men and women without a history of infertility, but who were willing to have children, and both sexes who were diagnosed with infertility in retrospective studies), found that caffeine, regardless of the intake dose, didn’t seem to increase the infertility risk. Yet, researchers noted the quality of evidence for this conclusion was low and to treat it with caution.

So in the absence of anything concrete at this stage, if you’re trying for a baby, it can do no harm to trial reducing your caffeine intake and seeing for yourself how that supports you.

Stop smoking

♀ ♂ The British Fertility Society states that smoking reduces the chances of conception for both men and women, regardless of whether e-cigarettes or conventional cigarettes are smoked.

♀ For women, it has long been established that a history of increasing tobacco exposure is associated with lower levels of the female sex hormone, oestradiol, and less oocytes (cells in an ovary which may divide to form a mature egg / ovum) and embryos being retrieved in those undergoing assisted reproduction cycles.

♂ For men, this is backed up by the majority of evidence.

♀ Additionally, a retrospective study of 225 women undergoing IVF found that implantation rate was lower in women who were exposed to second hand smoke (living with a partner who regularly smoked), compared to those who weren’t exposed to smoke (12.6% vs 25.0%), as was the pregnancy rate (20.0% vs 48.3%). In fact, the data revealed that the impacts of second-hand smoking were equally as damaging as directly smoking on fertility. So, if your partner or someone you live with smokes, you may want to encourage them to consider quitting.

What’s more, smoking, among many other harmful affects, can restrict essential oxygen from getting to your baby, should you conceive, so it’s wise to quit now if you’re planning on becoming a parent.

♂ A couple of extra tips for men:

Embrace loose fitting underwear

Yes, you read correctly. It’s established that healthy sperm production relies on a testicular temperature that’s below body temperature. Testicular temperature correlates highly with scrotal temperature. It’s also agreed that when scrotal temperature rises (it gets hotter in the area under the penis), it negatively impacts sperm quality and creation. Fortunately, scrotal and testicular cooling can enhance semen quality.

Eat more omega-3 fatty acids rather than trans fats

Following a diet abundant in anti-inflammatory omega-3 fatty acids appears to enhance sperm health, quality and motility. Sources include oily fish, such as salmon, mackerel, anchovies, herring and sardines, whilst vegetarians or vegans may get their fill from algae / seaweed or supplements, like algae oil. Meanwhile, eating trans fats negatively impacts sperm quality. Therefore, it can be wise to limit fried, processed and commercially baked foods that are rife with industrial trans fats.

Reviewed by:

Anna Keeble MA BA Head of Content and Wellbeing Expert

Dr Claire Marie Thomas MRCGP DFSRH DTMH DipNLP MBChB BMedSci Medical Expert

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