Is watermelon good during pregnancy?

The only trials of watermelon itself in pregnancy are in severe pregnancy sickness. In a randomized trial in 128 Malaysian women discharged from hospital with hyperemesis gravidarum, adding about an eighth of a watermelon a day for two weeks led to a median weight gain of 0.55 lb (0.25 kg) against a loss of 1.1 lb (0.5 kg) on dietary advice alone, with better symptoms, appetite and wellbeing. It did not reduce readmission or the use of anti-sickness drugs.

Unsettled. Watermelon helped women recovering from hyperemesis eat and gain a little weight, in one open label trial with partly self-reported outcomes. It did not keep them out of hospital, and one trial is not yet a settled answer.

Myth. Watermelon is often said to prevent preeclampsia because of its citrulline and lycopene. Both were tested as supplements in pregnant women, and neither prevented or treated it.

What the trials found

The hyperemesis trial gave each woman two red-fleshed watermelons of about 8.8 lb (4 kg) and told her to eat an eighth of the flesh a day, in smaller portions, for two weeks. That is the amount instructed, and the trial did not measure how much was actually eaten. The women in the watermelon arm also got the same dietary advice leaflet as the control arm. At one week the median weight change was -0.11 lb (-0.05 kg) against -1.1 lb (-0.5 kg). Rehospitalisation and antiemetic use did not differ significantly, and the trial was too small to detect a difference in something as uncommon as readmission.

An earlier crossover trial in 72 women within a day of their first admission for hyperemesis had each woman taste four foods. Watermelon scored 7.0 out of 10 for agreeability, just behind apple at 7.2 and ahead of crackers and white bread. After tasting it, 10 percent gagged or vomited, against 4 percent for apple and 17 percent for white bread.

The preeclampsia claim does not survive the trials of the compounds behind it. In a double-blind trial in 115 French women who already had preeclampsia, oral L-citrulline did not lengthen pregnancy, with a hazard ratio for time to delivery of 0.90 (95% CI 0.62 to 1.31). The liver enzyme ALT was 65.1 against 33.2 on placebo, and systolic pressure at delivery was higher on citrulline. Those were pharmacological doses, far above what watermelon supplies. In a pilot trial in 36 pregnant women with chronic hypertension, 3 g of L-citrulline twice a day for 8 weeks did not lower diastolic pressure, though the trial was too small to detect changes under 9 mmHg. A meta-analysis of 19 prevention trials of antioxidant supplements, lycopene among them, found no reduction in preeclampsia, a risk ratio of 0.89 (95% CI 0.79 to 1.02).

Sugar is the other common worry. A meta-analysis of 5 cohort studies found no link between how much fruit women ate during pregnancy and gestational diabetes, a risk ratio of 1.18 with a confidence interval from 0.48 to 2.91. That covers fruit in general, with very high disagreement between studies, and has no watermelon-specific data. In a glycemic index test in 10 healthy Malaysian adults, watermelon scored 55, in the low range. That was one test of one fruit, other tables list watermelon higher, and a serving holds little carbohydrate.

Unsettled. Whether watermelon does anything for the common web claims, swelling, heartburn or leg cramps in pregnancy, is unknown. We found no trial of any of them.

Who should be careful

The caution with watermelon in pregnancy is food safety. The CDC advice on preventing Listeria, aimed at pregnant women and other higher risk groups, is to avoid cut melon left out for more than 2 hours, or 1 hour above 90 F, such as at a picnic or in a hot car. Listeria outbreaks from melon have mostly involved cantaloupe. Watermelon has its own record with Salmonella. In a New Zealand outbreak, the 15 people who fell ill were seven times more likely than 40 controls to have eaten watermelon, though no Salmonella was recovered from the food. A systematic review of Salmonella Javiana infections in the US named watermelons and tomatoes among the produce linked to human cases, without a risk estimate for pregnancy.

Not for everyone. The CDC advice for pregnancy is to avoid cut melon that has been left out for more than 2 hours, or 1 hour in heat above 90 F, such as at a picnic or in a hot car.

What expert bodies say

We found no expert body position on watermelon as a food for pregnancy. The CDC addresses it only as a food safety question, advising pregnant women and other higher risk groups to avoid cut melon left out for more than 2 hours.

How we searched

What would change this answer

• A multicentre randomized trial of watermelon in nausea and vomiting of pregnancy, large enough to measure readmission. We found none registered.
• Any trial of watermelon itself for swelling, blood pressure or preeclampsia in pregnancy. The supplement trials above do not answer what the whole fruit does.

More on the fruit itself is on the watermelon page.

Sources

1. ev-wmpg-01 · Randomized controlled trial(s) · randomized controlled trial, 2 arms, 2 weeks · n = 128
   CONCLUSION: Adding watermelon to the diet after hospital discharge for HG improves bodyweight, HG symptoms, appetite, wellbeing and satisfaction.
   
   Who: women after hospitalization for hyperemesis gravidarum, Malaysia; watermelon plus dietary advice leaflet vs leaflet alone
   Effect: weight change week 2: median +0.55 lb (0.25 kg) vs -1.1 lb (-0.5 kg) (P = 0.001); week 1: -0.11 vs -1.1 lb (-0.05 vs -0.5 kg) (P = 0.014); PUQE-24, appetite and wellbeing also better
   Certainty: Open-label single-center trial; outcomes partly self-reported.
   BMC Pregnancy Childbirth, 2023 · checked 2026-10-07 · we read the abstract
2. ev-wmpg-02 · Randomized controlled trial(s) · randomized controlled trial, 2 arms, 2 weeks · n = 128
   These participants were instructed to consume 1/8 of the whole fruit flesh daily, in further divided portions for the following two weeks and to read and heed the dietary advice leaflet.
   
   Who: women after hospitalization for hyperemesis gravidarum, Malaysia; two red-fleshed watermelons of about 8.8 lb (4 kg) each
   Effect: 1/8 of a whole watermelon's flesh per day, split into portions, for 2 weeks
   Certainty: Amount instructed, not measured intake.
   BMC Pregnancy Childbirth, 2023 · checked 2026-10-07 · we read the fulltext
3. ev-wmpg-03 · Randomized controlled trial(s) · randomized controlled trial, 2 arms, 2 weeks · n = 128
   However, rehospitalization for HG and antiemetic usage were not significantly different.
   
   Who: women after hospitalization for hyperemesis gravidarum, Malaysia
   Effect: rehospitalisation for HG and antiemetic use not significantly different between arms
   Certainty: Trial too small for rare outcomes such as readmission.
   BMC Pregnancy Childbirth, 2023 · checked 2026-10-07 · we read the abstract
4. ev-wmpg-04 · Randomized controlled trial(s) · randomized within-subject crossover trial, single tasting · n = 72
   RESULTS: On agreeability scoring, apple (mean±SD 7.2±2.4) ranked highest followed by watermelon (7.0±2.7) and crackers (6.5±2.6), with white bread ranked lowest (6.0±2.7); Kruskal-Wallis H test, p=0.019.
   
   Who: women 18 or older within 24 hours of first admission for hyperemesis gravidarum, under 16 weeks, Malaysia
   Effect: agreeability apple 7.2, watermelon 7.0, crackers 6.5, white bread 6.0 (p = 0.019); intolerant response apple 4%, watermelon 10%, crackers 11%, white bread 17%
   Certainty: Single small tasting, 10-minute outcome.
   BMJ Open, 2021 · checked 2026-10-07 · we read the abstract
5. ev-wmpg-05 · Randomized controlled trial(s) · multicentre randomized double-blind placebo-controlled trial · n = 115
   CONCLUSIONS: The current trial found no benefit of oral L-citrulline supplementation to females with PE regarding either the duration of pregnancy, fetal growth, or maternal and neonatal outcomes.
   
   Who: women with single-fetus preeclampsia enrolled before 36 weeks, France; oral L-citrulline vs placebo
   Effect: time to delivery HR 0.90 (95% CI 0.62 to 1.31); ALT 65.1 vs 33.2 UI; systolic BP higher at delivery (P = 0.015)
   Certainty: Pharmacological doses of citrulline, far above what watermelon supplies.
   Am J Clin Nutr, 2025 · checked 2026-10-07 · we read the abstract
6. ev-wmpg-06 · Randomized controlled trial(s) · early-phase randomized placebo-controlled feasibility trial · n = 36
   L-citrulline had no effect on diastolic BP (L-citrulline: - 1.82 95% CI (- 5.86, 2.22) vs placebo: - 5.00 95% CI (- 12.76, 2.76)), uterine artery Doppler or angiogenic biomarkers.
   
   Who: pregnant women with chronic hypertension, randomized at 12 to 16 weeks, 3 g L-citrulline twice daily (n = 24) or placebo (n = 12) for 8 weeks
   Effect: diastolic BP change -1.82 mmHg (95% CI -5.86 to 2.22) vs placebo -5.00 (-12.76 to 2.76); underpowered for changes under 9 mmHg
   Certainty: Feasibility trial; supplement doses, not food.
   Reprod Sci, 2024 · checked 2026-10-07 · we read the abstract
7. ev-wmpg-07 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized clinical trials · n = 19 trials
   The antioxidants used in these studies were vitamins C and E, selenium, l-arginine, allicin, lycopene and coenzyme Q10, none of which showed beneficial effects on the prevention of preeclampsia (RR: 0.89, CI 95%: [0.79-1.02], P = 0.09; I2 = 39%, P = 0.04) and other outcomes.
   
   Who: pregnant women in randomized trials of oral antioxidants (vitamins C and E, selenium, L-arginine, allicin, lycopene, coenzyme Q10)
   Effect: preeclampsia RR 0.89 (95% CI 0.79 to 1.02), I2 39%
   Certainty: Supplements pooled together; no trial of watermelon itself.
   Nutr Metab Cardiovasc Dis, 2018 · checked 2026-10-07 · we read the abstract
8. ev-wmpg-08 · Observational data · meta-analysis of cohort studies · n = 5 cohort studies
   No link was obtained between fruit consumption during the pregnancy and GDM onset (1.18, 95 % CI: 0.48, 2.91; I2:94.6 %, p = 0.0001).
   
   Who: women in cohort studies, highest vs lowest fruit intake
   Effect: during pregnancy RR 1.18 (95% CI 0.48 to 2.91), I2 94.6%; before pregnancy RR 0.95 (0.91 to 0.99)
   Certainty: Fruit in general; very high heterogeneity; no watermelon-specific data.
   Complement Ther Med, 2020 · checked 2026-10-07 · we read the abstract
9. ev-wmpg-09 · Randomized controlled trial(s) · randomized crossover glycemic index test · n = 10
   Similarly, the glycemic index of pineapple, 82+/-4, was significantly greater than those of papaya, 58+/-6, watermelon, 55+/-3, and durian, 49+/-5 (p<0.05).
   
   Who: healthy volunteers (5 women, 5 men), 50 g available carbohydrate portions in random order
   Effect: GI watermelon 55 +/- 3, papaya 58, durian 49, pineapple 82
   Certainty: One test per fruit, Malaysian fruit; other GI tables list watermelon higher; low carbohydrate per serving.
   Asia Pac J Clin Nutr, 2008 · checked 2026-10-07 · we read the abstract
10. ev-wmpg-10 · Observational data · case-control outbreak investigation · n = 55
    RESULTS: The case control study included 15 cases and 40 controls and found that cases were seven times more likely to have eaten watermelon compared with controls (p=0.026).
    
    Who: 15 cases and 40 controls, Gisborne region, New Zealand, 2009
    Effect: cases 7 times more likely to have eaten watermelon (p = 0.026); watermelons traced to one grower
    Certainty: Single outbreak; no Salmonella recovered from food samples.
    N Z Med J, 2010 · checked 2026-10-07 · we read the abstract
11. ev-wmpg-11 · Observational data · systematic review of observational studies and outbreak reports · n = 12 studies
    Consumption of fresh produce (tomatoes and watermelons), herbs (paprika-spice), dairy products (cheese), drinking contaminated well water and animal contact were associated with human S. Javiana infections.
    
    Who: human S. Javiana infections in 12 published studies and outbreak reports
    Effect: watermelon and tomatoes among food exposures associated with infection
    Certainty: Qualitative synthesis; no risk estimate for pregnancy.
    PLoS One, 2019 · checked 2026-10-07 · we read the abstract
12. ev-wmpg-12 · Position of an expert body · agency consumer advice · n = —
    Cut melon left out for more than 2 hours (1 hour if it's exposed to temperatures hotter than 90°F, such as a picnic or hot car)
    
    Who: pregnant women and other higher-risk groups
    Effect: avoid cut melon left out more than 2 hours (1 hour above 90 F)
    Certainty: General melon advice; listeriosis outbreaks have mostly involved cantaloupe.
    US CDC, Preventing Listeria Infection (Safer Food Choices) · checked 2026-10-07 · we read the section