Colleen O’Rourke is a women’s fertility expert. She has been teaching women and couples natural family planning (NFP) for over 20 years, and is now in charge of all the volunteer teachers at one of the largest NFP organizations in the world, the Couple to Couple League (CCL).
In her late 20’s however, Colleen was trying to avoid pregnancy however she could. She was advised by her doctor to get on Depo-Provera, otherwise known as the birth control shot. “I trusted my family doctor… She recommended what she said was ‘the wonderful option of using Depo-Provera.’ She said she would even give this to her own daughter, that’s how wonderful it was.”
Indeed, in the first few months, Colleen was happy with Depo. The only effect was the total discontinuation of her period, which she thought was convenient, especially since she was very athletic and played multiple sports. Per the Depo schedule, Colleen would return to her doctor to get a shot every three months. Each time, she would fill out a questionnaire about her health and how she was responding to the drug.
About 9 to 12 months into her Depo regimen, she started feeling depressed and experiencing obsessive thoughts. It was time for another shot, but when she went to the doctor for her next dose of Depo, they found that her blood pressure was abnormal, and that she was indeed suffering from depression. They decided she shouldn’t get another shot.
That’s when the doctor first broke the news to her: even though Colleen would be discontinuing the prescription, “You won’t be able to get pregnant for another year,” her doctor said.
What Depo does to your endometrium
One of the documented (and intentional) effects of Depo-Provera is its impact on the lining of the uterus, known as the endometrium.
In a natural cycle, hormonal changes that prepare for and trigger ovulation also lead to the thickening of the endometrium. In case a child is conceived during that cycle, the embryo would implant within this rich and nutritive lining, and continue being able to grow. In the absence of conception, the thicker lining that was hence built, now useless, is sloughed off. This results in a normal menstrual period.
In Depo-Provera’s documented mechanism of action, we read that “progestins such as medroxyprogesterone,” the principal artificial hormone contained within the shot, “lead to atrophy of the endometrial tissue. They may also suppress new growth and implantation.” In other words, the endometrium doesn’t grow as it would in a normal, natural cycle, unimpeded by Depo. Instead, “it becomes thin and atrophic.” (For those unfamiliar with the term “atrophic,” it comes from the verb “atrophy,” which literally means “to waste away.”)
This mechanism explains one of the ways in which Depo acts as a contraceptive, and why a woman’s period will be suppressed when she’s on Depo. In fact, the product label for this drug reports that “As women continue using Depo-Provera CI…. in clinical studies of Depo-Provera CI, by month 12, amenorrhea (absence of periods) was reported by 55% of women, and by month 24, amenorrhea was reported by 68% of women using Depo-Provera CI.” As you can see from these statistics, the large majority of women on Depo simply do not have periods.
The return to fertility after stopping Depo can take a while
At the same time Colleen stopped Depo, she started charting her cycle using the Sympto-Thermal Method, a method of natural family planning (sometimes called fertility awareness methods) which includes following two signs of fertility: cervical fluid (sometimes called cervical mucus) and basal body temperature.
Colleen reports that it took several months before her cervical fluid production resembled a pattern of fertility, and before she saw the tell-tale basal body temperature rise that indicates ovulation has occurred. Both a distinctive fertile cervical fluid pattern and a post-ovulatory basal body temperature rise are signs of a normal, fertile menstrual cycle; the long delay Colleen witnessed before seeing these signs of fertility was just as her doctor had predicted.
For women like Colleen, a concerning, yet little-known side-effect of Depo-Provera is the very slow return of a normal cycle after one stops the injections. Unlike other hormonal contraceptive methods, data suggest that Depo-Provera’s effect on fertility is much more long-lasting after one quits the method. This can be especially dismaying if a woman has quit Depo in an effort to conceive a child—and confusing if she is unaware of these lingering effects of Depo on her fertility.
Again, the drug’s label confirms this effect, stating: “The median time to conception for those who do conceive is 10 months following the last injection with a range of 4 to 31 months, and is unrelated to the duration of use.” However, trying to find additional data on this issue is difficult, as there are only a few studies that contain any information about the average return to fertility after discontinuation of Depo.
I find it strange that so little research has been done on this subject, and that medical authorities seem content to rely on just a few, older studies on Depo and fertility. At best, it shows a real disinterest in women’s fertility, and for their natural concerns about becoming mothers when they’re ready to do so—at worst, it shows outright disdain.
Long term effects of Depo: Could miscarriage be one of them?
One effect of Depo-Provera that is not formally documented, but was experienced by Colleen and other women who have been on Depo, is the inability to keep a pregnancy—that is, miscarriage. Sadly, this happened to Colleen not just once, but three times.
“We were very excited when we got pregnant,” she remembers. “When we were 6 weeks along, we went to the doctor” for a confirmatory ultrasound. After the ultrasound, “the doctor walked in, and she told me that it looked like I had a blighted ovum, and that I was going to miscarry.” A blighted ovum, Colleen explains, is when “the baby is able to attach, but once attached, no nutrients are there to help your pregnancy progress. It’s just an empty sac, there is nothing inside.”
Colleen faults the long-term impact of Depo-Provera for her three miscarriages. While other key fertility functions returned, like ovulation, production of fertile cervical fluid that led to her getting pregnant, and even a thick enough endometrium to facilitate the implantation of the embryo at 6-9 days after conception, Colleen believes that the endometrium was still not providing the nutrients which would insure the survival of the child. At 6 weeks, their first child was dead—a crushing experience for Colleen.
All told, this experience happened three times to Colleen, the last one being right before Christmas. She and her husband had waited a whole year hoping her uterus would heal, and that its normal functioning would be restored.
Colleen’s experience of serial miscarriages following Depo is sadly not the only one, as one can read in forums like this one or that one, and one can surmise that many more women have gone through these very painful events. But solid studies to confirm the existence of this issue are lacking, preventing anyone from making a definite determination as to the nature of the relationship between miscarriages and Depo. Could we suspect that the conclusions of a would-be study would be so detrimental to Depo-Provera that it would lead to a general outrage?
“You need to know what you’re putting in your body”
Even if the data from one study showed a relatively low percentage of women experiencing miscarriages after Depo, this powerful drug is still prescribed so often that the sheer number of attributable miscarriages would likely shock us. In the US alone, 1.7 million women used the shot in 2019, according to the United Nations report. Worldwide, that number is a staggering 74 million, mostly in developing countries located in sub-Saharan Africa and Central and South America. That number was only 17 million in 1990, which means that use of Depo has increased by 435% since then, despite all the documented side effects and risks of this drug.
To put numbers in absolute terms: if only 1% of Depo users have a miscarriage after they quit the shots, that would mean 740,000 miscarriages (and 740,000 brokenhearted mothers) worldwide. Something to think about for women who are concerned about their long-term fertility, and for doctors who advise them.
After summing up her experience with Depo, Colleen’s last word is a message for all women: “You need to know what you’re putting in your body, you need to know what the side effects are, and you need to stop taking this stuff…” She has a message for their doctors, too: “Doctors need to stop giving these drugs to patients who trust them. They really do.”
Given the serious risks and side effects inherent to Depo-Provera use, and the wide availability of effective birth control alternatives, do women really need Depo? We don’t think so. That’s why, in Natural Womanhood’s petition to the FDA, we are calling for the removal of the Depo-Provera birth control shot from the market. If you agree that this dangerous product should be removed from the market, and that women deserve better information about the evidence-based risks and side effects of hormonal contraception, please sign our petition today.
Additional Reading:
FDA Citizen’s Petition on Birth Control: Shocking Stories of How Women Are Getting Hurt
I’ve been on the depot shot since Feb 2019 and I had my last shot in October 2021. I had a few light periods in Jan 2022 if you can even call them that but nothing since. Wanting to have a baby with my husband in the next few years but scared that it will take a very long time. I was never told about most of the side effects and my doctor never did evaluations between shots.