Most fertility gains come from a handful of changes you can start today: eating better, reaching a healthier weight, timing intercourse correctly, and cutting out a few specific exposures. These adjustments won’t guarantee conception, but they shift the odds meaningfully for both partners. Here’s what the evidence actually supports.
Know Your Fertile Window
Your highest chance of conceiving from a single act of intercourse falls on the day before ovulation and the day of ovulation itself, with roughly a 29 to 39 percent probability on each of those days. But the fertile window is wider than most people realize. Sperm can survive in the reproductive tract for up to five days, so intercourse anywhere from five days before ovulation through the day after it can result in pregnancy. Even five days out, the probability per encounter is still above 20 percent.
For most women with regular cycles, ovulation happens about 14 days before the next period starts. Ovulation predictor kits, which detect a hormone surge in urine, give you roughly 24 to 36 hours of advance notice. Having intercourse every one to two days during the fertile window gives you the best coverage without needing to pinpoint the exact day.
Shift Toward a Mediterranean-Style Diet
What you eat affects ovulation regularity, egg quality, and sperm production. The strongest dietary evidence points to a Mediterranean-style pattern: vegetables, fruits, whole grains, legumes, fish, and olive oil, with less red meat and processed food. Women who closely follow this pattern have about a 22 percent higher likelihood of achieving a clinical pregnancy compared to those who don’t.
The benefits likely come from the combination of antioxidants, healthy fats, and lower inflammation rather than any single food. You don’t need to overhaul your diet overnight. Swapping refined grains for whole grains, adding a few more servings of vegetables per week, and choosing fish over red meat two or three times a week moves you in the right direction. Both partners benefit from these changes.
Get to a Healthy Weight
Body weight is one of the strongest modifiable factors in fertility. A BMI between 18.5 and 24.9 is associated with the most regular ovulation. Obesity, defined as a BMI above 30, increases the risk of abnormal ovulation and irregular menstrual cycles. Being significantly underweight disrupts ovulation too, sometimes stopping periods entirely.
The encouraging part: you don’t need to hit a perfect number. Losing just 2 to 5 percent of your body weight can improve your chances of conceiving and having a healthy pregnancy. For someone weighing 200 pounds, that’s 4 to 10 pounds. Even modest changes in body composition help restore hormonal balance and improve ovulatory function.
Supplements That Have Real Evidence
Folic acid is non-negotiable. The CDC recommends 400 micrograms daily for all women who could become pregnant, primarily to prevent neural tube defects. Start taking it at least one month before you try to conceive, though earlier is better.
CoQ10 is the supplement with the most promising fertility-specific data. It supports mitochondrial function in eggs, which matters because egg cells are among the most energy-demanding cells in the body. Clinical trials have used 200 mg three times daily (600 mg total) for 60 days in women with diminished ovarian reserve, showing improved ovarian response. For women with normal ovarian reserve, 200 mg per day for 30 to 35 days before attempting conception has been studied. CoQ10 is also beneficial for men (more on that below).
Vitamin D deficiency is common and has been linked to lower fertility in observational studies. If you haven’t had your levels checked recently, it’s worth doing.
What Male Partners Can Do
About half of infertility cases involve a male factor, so optimizing sperm quality matters just as much. Two supplements stand out in clinical trials involving nearly 1,800 subfertile men. CoQ10 produced the largest increase in sperm concentration, adding roughly 6 million sperm per milliliter compared to placebo. Carnitine, an amino acid the body uses for energy metabolism, was the most effective for improving sperm motility, increasing it by about 12 percentage points.
Heat is the most underappreciated threat to sperm production. Testicles need to stay cooler than core body temperature, which is why they sit outside the body. A study tracking men who used a sauna twice weekly for three months found significantly impaired sperm count and motility by the end of the exposure period. The good news: all effects fully reversed within six months of stopping. Hot tubs, laptops on laps, and prolonged cycling can have similar effects. If you’re trying to conceive, minimize regular heat exposure to the groin area.
Tight underwear gets a lot of attention, but the evidence is weaker than for direct heat sources. Switching to boxers won’t hurt, but skipping the hot tub matters more.
Caffeine, Alcohol, and Smoking
Caffeine up to about 200 mg per day (roughly one 12-ounce cup of coffee) appears safe for fertility. A meta-analysis found no significant effect on the ability to conceive at intakes up to 400 mg daily. The risk shows up more clearly during pregnancy itself: at 300 mg per day, the risk of miscarriage rises by 37 percent compared to no caffeine. At 600 mg daily, that risk more than doubles. Keeping intake under 200 mg per day gives you a comfortable margin.
Alcohol has a dose-dependent relationship with fertility. Heavy drinking clearly impairs both ovulation and sperm production. Even moderate intake (more than a few drinks per week) has been associated with longer time to conception in some studies. There’s no established “safe” amount for optimizing fertility, so less is better.
Smoking damages fertility on every front. It accelerates egg loss, reduces sperm quality, and increases miscarriage risk. Quitting is one of the single highest-impact changes either partner can make.
Manage Stress, but Don’t Blame It
Chronic stress can disrupt the hormonal signals that trigger ovulation, and high cortisol levels may interfere with implantation. That said, the relationship between stress and fertility is complicated, and “just relax” is neither helpful nor accurate advice. Plenty of highly stressed people conceive without difficulty.
What does help: regular moderate exercise (which improves insulin sensitivity and hormone balance), adequate sleep, and whatever stress management genuinely works for you. Intense endurance exercise, on the other hand, can suppress ovulation in some women, so balance matters more than intensity.
When to Seek a Specialist
The standard timeline, per the American Society for Reproductive Medicine, is 12 months of trying for women under 35 and 6 months for women 35 and older. For women over 40, earlier evaluation is reasonable. These timelines assume regular unprotected intercourse during the fertile window.
Certain signs warrant evaluation sooner regardless of age: cycles shorter than 21 days or longer than 35 days, known conditions like endometriosis or polycystic ovary syndrome, a history of pelvic infections, or a male partner with a known testicular issue. A basic fertility workup is straightforward and can identify common problems quickly, so there’s no reason to wait out the full timeline if something feels off.