Vulvodynia is a chronic pain condition of the vulva that affects between 3 and 15% of women. What makes vulvodynia particularly challenging is the cause is unknown and even the mechanism of the pain itself has not been well elucidated. For that reason, like many inadequately studied conditions, there are a myriad of therapies and recommendations that are based more on opinion, and often what amounts at best to be quasi-science. One example, which I have posted about before, is the low oxalate diet. This diet is recommended by many providers and has been turned into a veritable cottage industry all based on a single case report. It has been disproven by several other studies, but still I am asked about it on a regular basis. That is sad.
Suffice it to say good, prospective data on vulvodynia is needed.
One vulvodynia myth/idea/hypothesis that has been floating about for years is that it related to birth control pills. However, I have always had a lot of issues with this concept as:
A) The studies are often underpowered or otherwise not well designed to answer the question. They are also conflicting.
B) If you have sex you are more likely to be diagnosed with vulvodynia as a percentage of women with this condition only have pain with sex. If you have sex you are more likely to be on the birth control pill. Controlling for this confounder is hard.
C) I have never seen anyone improve when they stopped the pill and I see a lot of women with vulvodynia (although granted, if they improved they probably wouldn’t be seeing me).
D) Women with vulvodynia are more likely to have other pain conditions, such as painful periods, so may be more likely to be on the pill on the pill for pain before they even initiate sex thus skewing the stats
E) I have a hard time with the biologic plausibility. While hormones definitely have a role in pain for women (the increased incidence of chronic pain for women vs. men starts with puberty and ends with menopause), but women are exposed to far more estrogen during pregnancy than the pill can ever hope to introduce and we certainly don’t see an increased incidence during pregnancy. While it s possible that the progesterone in pregnancy, different from progestins in the pill, might have a protective role it’s all so “possible” and “maybe” that, well, it’s just a hypothesis and not a robust one at that.
However, a new study gives us more information. Reed et. al, (her group is a veritable power house of vulvodynia publishing) looked at oral contraceptive use and the risk of vulvodynia in a longitudinal population-based study published in BJOG. They evaluated 906 women, just over 8% were found to have vulvodynia and almost 21% had a history of vulvodynia. They looked at contraception use, reasons for starting and stopping, and a host of other demographic variables. They also looked at the timing of oral contraceptive initiation and the onset of vulvodynia symptoms.
There was no association between vulvodynia symptoms and oral contraceptives, not even for women who took the pill for 10 or more years.
The study is large and uses validated questionnaires. It also gathered a lot of data that simply had not been addressed in previous studies. The 2 biggest issues with the study are the diagnosis of vulvodynia was based on a survey (albeit a validated one) and it wasn’t prospective, meaning women were not followed over the years so there could be some recall bias about pill use.
The study can’t prove cause and effect, but it does provide the most evidence to date regarding oral contraceptives and vulvodynia and the two do not appear to be related. A prospective study would be ideal, but this study is better than the current literature.
Stopping pills can lead to other medical concerns (irregular bleeding, painful periods, and of course pregnancy) and it is hard enough to have a difficult to treat medical condition, never mind someone feel that you are somehow responsible because of a medical that you took.
Unless other evidence arises, women and their providers should not be concerned that vulvodynia is associated with contraceptive pills.