Brief Answer:
Bio identical hormones

Detailed Answer:
The two brand name medications you have listed proper pharmaceutical medications that are formally and systematically regulated by the FDA. And this is a very good thing.

Stomach cramps and related side effects are possible with both these medicines. You may wish to call the prescribing doctor and discuss if you can stop them temporarily to see if the symptoms improve. Then later you can restart one at a time to see which one, if any, was responsible for the stomach cramps.

Let me tell a little bit about Bioidentical hormones.

Bioidentical hormones are identical to the hormones that women make in their bodies. Bioidentical hormones are sometimes called “natural” hormones—even though they are made in a laboratory—because they come from plant sources before being altered to be like human hormones. Not all hormones made from natural sources are bioidentical.
There are two types of bioidentical hormone products:
Pharmaceutical products. These products have been approved by the U.S. Food and Drug Administration (FDA). Their quality and safety is regulated so it is the same high-quality product every time.
Custom-made products. When many people think of bioidentical hormones, they think of custom-made products. These are made in a compounding pharmacy(a pharmacy that mixes medications according to a doctor’s instructions). These products may contain varying amounts of two or three types of estrogen, often mixed with other hormones. Although the individual ingredients are approved by the FDA (except for estriol), the compounds themselves (the final product after the ingredients are combined) are not. Because these compounds are not regulated by the FDA, they can be of low quality. The amount of hormone can change with each batch.
Most menopause specialists start with FDA-approved products because they’ve been proven to be safe and effective. For women who cannot take these products due to allergies, or who need a special prescription, custom-made products are an option. Because the quality of custom-made products can vary, however, it is safer to use pharmaceutical products. This way, you’ll know exactly what you’re getting and how much.
If your doctor prescribes Hormone Therapy (HT) for Menopause, the FDA recommends using the lowest possible dose for the shortest time needed to relieve symptoms. The idea is to avoid taking too much medication for too long to reduce potential risks linked to HT. You might also want to consider the wide range of non-hormonal options available to treat menopausal symptoms.
Finding the type of treatment that works best for you may take some time. Whatever you choose, your doctor will monitor your therapy regularly.

Menopause is a natural stage in a woman’s life. Some symptoms such as hot flashes can go away in a few years. Others, such as vaginal dryness, often do not go away. Many treatment options exist for problems that come with menopause.

To date, there is no scientific proof that bioidentical hormones, whether prepared by a compounding pharmacy or pharmaceutical company, are safer to use than other forms of HT. All forms of HT may have potential risks, whether compounded or pharmaceutical, bioidentical or not.

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