Short answer: in a large North American preconception study, women and men who drank seven or more sugar-sweetened beverages a week took longer, on average, to conceive. The link was strongest for sugared sodas and energy drinks. Diet soda and fruit juice showed little association. It's an observational finding, so it doesn't prove that soda causes slower conception, but cutting back on sugary drinks is low-cost, low-risk, and good for health in other ways too.
This post covers sugar-sweetened drinks. If you're wondering about diet drinks and sweeteners, we cover those separately in artificial sweeteners and reproductive health.
What the study measured
The study, led by Elizabeth Hatch and published in Epidemiology in 2018, followed 3,828 women planning a pregnancy and 1,045 of their male partners. Participants reported their beverage intake and were followed for up to 12 menstrual cycles to see how long it took to conceive.
The key measure is the fecundability ratio (FR): the chance of conceiving in a given cycle compared with a reference group. An FR of 1.0 means no difference. An FR of 0.80 means about a 20% lower chance of conception per cycle. It doesn't mean 20% of people couldn't conceive; it means conception tended to take longer.
What it found
Sugar-sweetened beverages and fecundability (7 or more per week vs. none)
| Who was drinking | Any sugar-sweetened beverage | Sugared sodas specifically |
|---|---|---|
| Female partner | FR 0.81 (95% CI 0.70–0.94) | FR 0.75 (95% CI 0.59–0.95) |
| Male partner | FR 0.78 (95% CI 0.63–0.95) | FR 0.67 (95% CI 0.51–0.89) |
Source: Hatch EE et al., Epidemiology 2018;29(3):369–378 (PMID 29384791). Lower FR = lower per-cycle chance of conception.
In plain terms, drinking seven or more sugar-sweetened beverages a week was associated with roughly a 19% lower per-cycle chance of conception when the woman drank them and about 22% lower when the man did. For sugared sodas, the associations were larger. The authors concluded that sugar-sweetened beverages, particularly sodas and energy drinks, were associated with lower fecundability, while diet soda and fruit juice showed little association.
Why both partners matter
It's easy to read fertility nutrition advice as aimed only at women. This study is a useful reminder that the male partner's habits showed associations of similar size. Earlier cross-sectional studies, noted by the authors, had already linked sugar-sweetened beverages with poorer semen quality.
Why might sugary drinks matter?
The study can't say why, but there are plausible pathways worth knowing about. Sugary drinks deliver a lot of sugar quickly without fullness, which can contribute to weight gain and to insulin resistance, both of which are linked to ovulation problems and to poorer sperm parameters. Energy drinks add a large caffeine load on top. These are hypotheses, not findings from this study.
The limits
- Observational design. People who drink a lot of soda may differ in diet, sleep, weight or other habits. The researchers adjusted for many factors, but residual confounding is always possible.
- Self-reported intake. Beverage questionnaires estimate typical intake and carry measurement error.
- Planners, not a random sample. Participants were people actively planning pregnancy who enrolled in an online study.
- One cohort. It's a well-designed study, not the final word.
The energy drink caffeine math
Energy drinks combine sugar and caffeine, and the caffeine varies more than most people realize. FDA's figures:
Caffeine in common drinks (FDA ranges)
| Drink | Caffeine |
|---|---|
| Energy drink, 16 fl oz | about 54–328 mg |
| Energy drink, 12 fl oz (some brands) | about 41–246 mg |
| Brewed coffee, 12 oz | about 113–247 mg |
| Decaf coffee, 8 oz | about 2–15 mg |
Source: FDA, "Spilling the beans: how much caffeine is too much?"
FDA says up to 400 mg a day is generally not associated with negative effects in healthy adults, and advises people who are pregnant, trying to become pregnant or breastfeeding to talk with their health care provider about whether to limit caffeine. One large energy drink at the top of FDA's range, plus a coffee or two, can reach that ceiling. If you also use pre-workout, add that in; our gym supplements guide covers the stacking problem.
For what the fertility research says about caffeine specifically, see our alcohol and caffeine limits, howtohaveababy.com's caffeine and fertility guide, and fertilestart.com's summary of what the research says on caffeine and alcohol.
What about juice?
In this study, fruit juice showed little association with fecundability. That doesn't make juice a health drink: it's still a concentrated source of sugar without the fiber of whole fruit. If you like juice, a small glass with a meal is a different thing from juice as your main drink. Whole fruit is the better everyday choice.
Sugary drinks that don't look like soda
Many sugar-sweetened drinks don't register as "soda" when people tally their intake. Check these too:
- Coffee-shop drinks: flavored lattes, frappés and syrups can carry as much sugar as a can of soda.
- Bottled teas and lemonades, including ones marketed as natural or organic.
- Sports drinks sipped through the day rather than during long exercise.
- Flavored waters and "vitamin" drinks, some of which are sweetened.
- Smoothies and juice blends from shops, which can be large and very sweet.
- Kombucha, which varies widely in residual sugar.
On U.S. packaged drinks, the Nutrition Facts panel lists Added Sugars separately from total sugars. That line is the fastest way to compare two bottles, and it helps you spot a "healthy-looking" drink that is mostly sugar. Serving size matters too: some bottles count as more than one serving.
Practical swaps
Swap ideas for both partners
| Instead of | Try |
|---|---|
| Regular soda | Sparkling water with citrus, cucumber or a splash of juice |
| Energy drink | A measured coffee or tea, and a look at your sleep |
| Sweet tea or lemonade | Unsweetened iced tea with lemon, or half-and-half while you adjust |
| Sports drink at your desk | Water; keep electrolyte drinks for long, sweaty exercise or illness |
| Large juice | Whole fruit, or a small juice with a meal |
If you sweat heavily at work or in training, our electrolytes for TTC and pregnancy guide covers lower-sugar options and what to check on the label.
A two-week reset plan
- Count for three days. Write down every sweetened drink, including coffee-shop drinks, sweet tea and sports drinks.
- Pick the biggest source and replace it first, rather than quitting everything at once.
- Keep the ritual. If the afternoon soda is a break, keep the break and change the drink.
- Do it together. The study linked both partners' intake to time to pregnancy, so this is a shared change.
- Watch the caffeine as you swap. Replacing soda with energy drinks or large coffees trades one issue for another.
Drinks are one piece of the diet. conceiveguide.com's conception diet evidence review and our fertility diet hub cover the rest of the plate.
When to see a doctor: if you've been trying for 12 months, or 6 months if the female partner is 35 or older, ASRM recommends an infertility evaluation for both partners. Don't wait on diet changes if your cycles are irregular.
Sources
- Hatch EE, Wesselink AK, Hahn KA, et al. Intake of sugar-sweetened beverages and fecundability in a North American preconception cohort. Epidemiology. 2018;29(3):369–378. PubMed 29384791
- FDA. Spilling the beans: how much caffeine is too much? fda.gov
- ASRM Practice Committee. Definition of infertility: a committee opinion (2023). asrm.org (PDF)
Keep reading
Frequently Asked Questions
Does drinking soda affect fertility?
In a 2018 study of 3,828 women and 1,045 male partners, drinking seven or more sugar-sweetened beverages a week was associated with a lower per-cycle chance of conception for both partners, and the association was stronger for sugared sodas. The study was observational, so it shows a link rather than proof of cause.
Is diet soda better for fertility than regular soda?
In this study, diet soda showed little association with fecundability. Artificial sweeteners raise their own questions, which we cover in a separate guide, but diet soda was not linked to slower conception here.
Are energy drinks bad when trying to conceive?
The study's authors highlighted sodas and energy drinks as most associated with lower fecundability. Energy drinks also vary widely in caffeine; FDA lists about 54 to 328 mg per 16 ounces. Talk with your provider about your total caffeine while trying to conceive.
Does fruit juice affect fertility?
Fruit juice showed little association with fecundability in this study. It is still a concentrated sugar source, so whole fruit is the better everyday choice.
Does the male partner's soda intake matter?
Yes. Male intake of seven or more sugar-sweetened beverages a week was associated with lower fecundability, and the association with sugared soda was among the largest in the study.
When lifestyle and nutrition changes have been addressed and you're ready to look at treatment options, understanding the clinical path is the next step.
Explore IVF Treatment Education →Part of the FertileStart family of fertility resources.