How Long Are Guppies Pregnant?

A guppy pregnancy typically lasts three weeks to four weeks. Pregnancy can take as long as 5 weeks in rare cases depending on the mother’s stress levels and health.

In this article, I’ll explain the guppy gestation process and what you need to be prepared for to raise healthy, happy guppy babies.

How Long Are Guppies Pregnant?

Guppies are pregnant from 21 days to 31 days on average. If the guppy mother is stressed in her environment or is unhealthy, her pregnancy may last up to 35 days or could be cut short by premature birth or miscarriage.

While a guppy’s initial pregnancy may only last a few weeks, you should know that your female guppy may get pregnant again soon after, even if she only mated once. Female guppies can store sperm for long periods of time. One mating session can result in up to six pregnancies, which typically occur in 30-day cycles.

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How Do You Know When a Guppy Is Going To Give Birth?

You’ll know your guppy is going to give birth based on her behavior, eating patterns, and physical appearance. Below, I’ll detail what to look out for in each of these categories.

You Witness Mating

If you keep male and female guppies in the same tank, they will most certainly mate, and this mating process is unmistakable. It will begin by the male chasing the female around the tank, and this mating ritual will last a few minutes before quick insemination occurs. In the following days, you may notice signs of pregnancy.

A Darkened Gravid Spot

One of the first things you will notice if your female guppy is pregnant is a darkened gravid spot that gets progressively darker as the gestation period goes on. The gravid spot is located at the base of the guppy’s tail where it meets her belly.

At first, this spot could be dark yellow in color, but can become nearly black as your guppy nears the end of her pregnancy. It will also get larger as the mother’s belly grows.

The gravid spot may appear spotted as your guppy gets closer to giving birth. Those spots are the eyes of the guppy fry!

They Try To Hide

Pregnant guppies will try to find a safe space in your tank to hide from other fish if they’re sensing that they’re about to give birth. This is unusual behavior for a guppy, as you know, since guppies tend to be very social.

If you find your guppy hiding, it may be time to move her to a different tank to prepare her for delivery.

They Get Aggressive

Pregnant guppies will get more aggressive when they’re expecting to ward off unwanted male attention. The females may even chase the males or bite them to keep them from trying to inseminate them again.

They Don’t Want To Eat

Guppies do get stressed when they’re pregnant, and just like humans, the stress affects their appetites. A pregnant guppy may avoid food, but it’s important to continue to try to feed her so she stays healthy. You want her to have all the nutrition she needs for her fry.

You See Small Dots

Guppies are livebearers, meaning the eggs develop inside of the female guppy’s womb. Once they’re fully developed, the mother will give birth to live babies.

As the eggs reach maturity, their translucent nature means you may be able to see their eyes through the eggs and through the mother’s belly. These eyes appear as tiny black dots near the gravid.

The Guppy’s Belly Gets Bigger

As with humans, the guppy’s belly will get bigger as the eggs mature. The fish could even develop an almost angular shaped belly or appear boxy.

How Many Babies Will My Guppy Have? 

A healthy guppy will produce anywhere between 20 to 120 babies per pregnancy. Of course, not all these fry will survive. In its lifetime, a female guppy can give birth to 2,000 fry.

The large range of fry per pregnancy depends on several factors including the female’s health, whether she is stressed, if she is eating well, her genetics, and her age. The older a guppy is when she is pregnant, the more babies she will likely have.

How Long Does It Take For Guppies To Give Birth?

It will take a guppy approximately four to six hours to deliver all her fry. If she is stressed, it could take as long as 12 hours to deliver.

As the fry are born, the healthy babies will eventually swim upward. Any unhealthy or stillborn guppy fry will fall to the bottom of the tank and should be removed.

If the delivery lasts longer than 12 hours, it is rare that many fry will survive.

How Do You Help A Guppy Give Birth?

To help your guppy give birth, first make sure to keep her healthy and happy. Consider her environment and food.

Her environment should be spacious and clean, and she should be given places to hide in the event the males continue to chase her after she becomes pregnant.

Her meals should include plenty of vegetables and protein, which can look like brine shrimp, bloodworms, spirulina, and peas. Fish flakes may have been sufficient when your guppy was not pregnant, but she will have a healthier pregnancy with an improved diet.

Do I Need To Separate A Pregnant Guppy From Other Fish?

You do not need to separate your pregnant guppy from other fish during her pregnancy. However, once she’s about to give birth, she must be moved to another tank for a few reasons.

Your pregnant guppy will become very stressed when she’s about to give birth. To ensure the healthiest babies, it’s important that she is moved to a peaceful space such as a birthing tank or a breeding box where she won’t be bothered.

In addition, guppies – especially the parents – will eat their young. It’s not exactly clear why they do this, but some scientists suspect that, at least for the mother, the pregnancy leaves her protein-deficient, so she immediately eats her babies.

When she is finished giving birth, remove her from the birthing tank immediately so she does not consume her young.

The fry should be left to mature in a separate tank for two to three months to protect them from their parents and other larger fish. If you choose to utilize a breeding box for the delivery, fry should be removed from the breeding box and put in a different tank, so their growth is not stunted.

In Conclusion

It takes anywhere from 21 days to 35 days for a guppy to give birth, and they need to be well-cared for during this time to make sure they deliver healthy fry. Remember, guppies are prolific breeders, so if you’re not planning on having lots of guppy babies, keep your males and females separated!