Update 10/17/19. After writing a review on the hair, skin, and nails supplement Halo Beauty, I received feedback from people on a topic I was not aware of. Many women started alerting me that one of the ingredients – saw palmetto – was linked to unplanned pregnancy by way of interfering with birth control pills. In over 20 years of investigating supplements, this was a new one. Sure enough, those women quickly pointed me to evidence. That is what I want to discuss here. Is saw palmetto really linked to getting pregnant? Does it interfere with birth control pills? Let's find out. Read the Halo Beauty review too.
What Is Saw Palmetto?
Saw palmetto (Serenoa repens) is a type of small palm tree common to Florida and Georgia that ranges from 2 feet to 10 feet tall. The tree produces berries that are used in dietary supplements. As a supplement, the herb is sometimes used to help prostate problems, especially begin prostatic hyperplasia (BPH), where the prostate grows in size as a man ages. This can cause problems during urination.
At least one study has shown the herb helped BPH symptoms as well as a prescription drug called finasteride which is used to treat BPH and hair loss.
How Does Saw Palmetto Work?
The berries in from the tree contain compounds like beta-sitosterol and others that seem to inhibit an enzyme called 5-alpha-reductase which converts testosterone into dihydrotestosterone (DHT). By blocking DHT formation, this is thought to stop the prostate gland from growing.
DHT also seems to be bad for hair too and some research has noted saw palmetto helps hair grow by blocking DHT. While there are not many studies, this blocking of DHT may be why the herbal is in hair supplements such as Halo Beauty.
Saw Palmetto And Birth Control Pills
Some women are concerned that supplements containing saw palmetto might interfere with birth control pills and put them at an increased risk of pregnancy. After I did some digging, I noticed other credible websites like WebMD mentioning this also.
I got more interested and decided to do a deep dive into the research.
I first searched the National Library of Medicine for:
- Saw Palmetto Birth Control
- Saw Palmetto Pregnancy
- Serenoa repens Birth Control
- Serenoa repens Pregnancy
I wanted to go right to the heart of the matter and reveal if anyone had gotten pregnant while taking this herbal supplement. No reports describing accidental pregnancy while taking this herbal supplement could be located.
In other words, there seems to be no direct evidence of anyone getting pregnant while taking this herb.
But, if that's the case, why are people saying this can happen?
Turns out, there is a reason.
Research suggests the herb has anti-estrogen effects. In other words, it lowers estrogen levels. The evidence for this is that in men with BPH, saw palmetto (480 mg/day, taken for 3 months) reduced estrogen levels.
This seems to be one of the main arguments for cautioning women against using this herb.
Basically, what they are saying is if the herb reduced estrogen in men, it might also reduce estrogen in women – and interfere with birth control pills. So far, however, human evidence is lacking. That doesn't mean this cannot occur. Rather it means it may not have occurred or have been noticed by anyone or reported to doctors if it did occur.
One ironic point is that as far back as the late 1960s, the herb was recognized as having estrogen-like properties. In other words, it didn't lower estrogen levels – it might raise them.
Saw Palmetto And Birth Defects
Testosterone is needed for proper fetal growth. If saw palmetto is anti-estrogenic and anti-DHT, what effect would that have on the growth of babies?
Animal studies have noted inhibiting the 5-alpha reductase enzyme during pregnancy is associated with abnormal male genitalia development. These studies used the prostate/hair growth drug finasteride and not saw palmetto. In some cases, the finasteride was injected rather than taken orally.
While there seems to be no direct evidence linking the herb to birth defects, the results from lab animal studies are too important to overlook. If you are pregnant, do not take this herb. The same goes for breastfeeding too. It's not worth the risk.
Supplements Containing Saw Palmetto
This herb often found in the following categories of supplements:
- Hair, skin and nails supplements
- prostate supplements
For example, it's found in popular hair supplements like Nutrafol and Halo Beauty. No reports of unplanned pregnancy in women taken these supplements could be located.
In contrast, Viviscal, does not contain this herb.
Does It Interfere With Birth Control Pills?
Various medical websites caution women about saw palmetto supplements while taking birth control pills. This is out of a fear the herb may reduce the effects of birth control pills and risk an unplanned pregnancy. However, the proof cited stems from lab animals and cells in test tubes. I can understand how women would be concerned although no reports of unplanned pregnancies in women while taking saw palmetto can be found.